MyPasTest: MRCS A Online - Jan Exam 2015
26. Surgical Specialities; General Surgery; Colorectal Surgery (36Qs)
01. A 46-year-old man attends colorectal clinic presenting with a 4 month history of a change in bowel
habit with blood mixed with stool. He has no relevant past medical history. What is the most appropriate
investigation? Single best answer - select one answer only.
Barium enema« YOUR ANSWER
Capsule endoscopy
Colonoscopy« CORRECT ANSWER
CT scan
Oesphagoduodenoscopy.
This 46-year-old male requires a lower GI endoscopy for his red flag symptoms of change in bowel habit
associated with PR bleeding. This test is the best investigation as it allows inspection of the bowel
mucosa, biopsy if required and is potentially even therapeutic, for example, if a polyp is seen this can be
removed by snare and sent for histology. It is an invasive test, requiring bowel preparation prior to the
procedure but he is otherwise well and there are no contradindications in undertaking colonoscopy. A
barium enema, though it could be useful, is not the best test for this patient. It may give an impression of
a lesion in the bowel wall but does not give such accurate information as colonoscopy in this case.
Furthermore he would still require an endoscopic biopsy if a lesion was seen. CT scans maybe useful for
detecting gross bowel pathology and staging for cancers but would not be as useful as colonoscopy here
as commented above. Oesphagoduodenoscopy (OGD) is useful if an upper GI source is suspected but
this patient has lower GI symptoms. Capsule endoscopy is an expensive test and not readily available. It
is useful for looking for a source of GI bleeding that occurs in the small bowel beyond the scope of the
OGD and proximal to the caecum/Terminal ileum which can be accessed by colonoscopy.
02. Theme: Abdominal system investigations
A Colonoscopy
B CT
C Endoanal ultrasound
D Evacuation proctogram
E Flexible sigmoidoscopy enema
F Mesenteric angiogram
G MRI
H Red cell scan
I Single contrast gastrografin.
For each of the following scenarios, select the most likely answer from
the above list. Each option may be used once, more than once, or not at all.
Scenario 1
Local invasiveness of rectal cancer in the pelvis.
A - Colonoscopy « YOUR ANSWER
G - MRI« CORRECT ANSWER.
G – MRI:
Tissue invasion within the pelvis by rectal cancer is best assessed with MRI as this modality gives the
best contrast resolution. MRI can identify whether the fascial envelope in which the rectum lies has been
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Dr Mohammed Shamsul Islam Khan, Medical Officer, Clinical Neuro-Surgery, National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh. Mobile: +880 1713 455 662, +880 1685 811979. E-mail: drsikhan@gmail.com
Page |
1541
MyPasTest: MRCS A Online - Jan Exam 2015
26. Surgical Specialities; General Surgery; Colorectal Surgery (36Qs)
breached, or has a margin which may be threatened with tumour during surgical resection. With this
technique, MRI can predict if neoadjuvant chemoradiotherapy needs to be given.
Scenario 2
Evidence of secondary spread to the liver.
B - CT« CORRECT ANSWER.
B – CT:
Hepatic metastases can be visualised by both MRI and CT. CT has better spatial resolution whereas MRI
has superior contrast resolution.
Scenario 3
A 35-year-old lady with passive and urge faecal incontinence following obstetric injury.
C - Endoanal ultrasound « CORRECT ANSWER.
C – Endoanal ultrasound:
The most suitable investigation here would be an endoanal ultrasound to visualise the internal and
external anal sphincters. Other investigations that need to be requested in such a patient would be
anorectal manometry (to measure resting and squeeze anal pressures) and rectal sensory thresholds.
03. Theme: Diarrhoea
A Amoebic dysentery
B Bacterial enterocolitis
C Colonic carcinoma
D Crohn’s disease
E Diabetes
F Irritable bowel disease
G Giardiasis
H Malabsorption
I Neuro-endocrine tumour
J Overflow (faecal impaction)
K Pancreatic exocrine insufficiency
L Pseudomembranous colitis
M Thyrotoxicosis
N Ulcerative colitis.
The following scenarios describe patients with diarrhoea. From the above list choose the most
appropriate cause. Each item may be used once, more than once, or not at all.
Scenario 1
A 35-year-old woman presents with a 1-month history of passing bloody diarrhoea/mucus up to seven times per
day and lower abdominal pain. She was previously fit and well and her problems started following an episode of
food poisoning in Thailand. She has associated lethargy and weight loss. On examination, she appears pale and
abdominal examination reveals some lower abdominal tenderness. Haemoglobin 9.8 g/dl, mean corpuscular
volume 60, white cell count 13 x 109/litre, erythrocyte sedimentation rate 65, C-reactive protein 130. A stool
culture is negative. Sigmoidoscopy demonstrates active proctitis.
A - Amoebic dysentery« YOUR ANSWER
N - Ulcerative colitis« CORRECT ANSWER.
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Dr Mohammed Shamsul Islam Khan, Medical Officer, Clinical Neuro-Surgery, National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh. Mobile: +880 1713 455 662, +880 1685 811979. E-mail: drsikhan@gmail.com
Page |
1542
MyPasTest: MRCS A Online - Jan Exam 2015
26. Surgical Specialities; General Surgery; Colorectal Surgery (36Qs)
N – Ulcerative colitis:
Interestingly, both ulcerative colitis and irritable bowel syndrome (IBS) appear to be triggered in a
proportion of patients following acute enteritis (the entity of post-infectious IBS is well established). The
symptoms and signs are those of an acute attack of colitis confirmed by sigmoidoscopy. Clearly, before
steroids are administered, stool culture must be performed, however, as in this case.
Scenario 2
A 24-year-old man presents to clinic with a few months of diarrhoea and abdominal pain. At colonoscopy, there is
patchy active inflammation affecting the transverse and right colon. Biopsies are reported as indeterminate colitis.
B - Bacterial enterocolitis« YOUR ANSWER
D - Crohn’s disease« CORRECT ANSWER.
D – Crohn’s disease:
This patient (on balance) has evidence of Crohn’s colitis. This is supported by rectal sparing and skip
lesions within the colon. It is not infrequent for biopsies to have insufficient findings to conclusively
support a diagnosis either of Crohn’s disease or ulcerative colitis and these are usually described as
indeterminate.
04. Theme: Treatments for anal pain
A Anal canal carcinoma
B Fissure in ano
C Low subcutaneous anal fistula (below the dentate line)
D Perianal abscess
E Perianal haematoma with supralevator extension
F Proctitis secondary to Crohn’s disease
G Radiation proctitis
H Solitary rectal ulcer syndrome
I Transphincteric anal fistula.
For each of the treatment options, select the most likely answer from the above list. Each option may be
used once, more than once, or not at all.
Scenario 1
Biofeedback
A - Anal canal carcinoma « YOUR ANSWER
H - Solitary rectal ulcer syndrome« CORRECT ANSWER.
H – Solitary rectal ulcer syndrome:
Solitary rectal ulcer syndrome is a relatively common cause of bright red rectal bleeding. It classically
produces an ulcer on the anterior wall of the rectum, but may also have a polypoid appearance. The
aetiology of the condition is incompletely understood but is thought to be a combination of internal
intussusception/anterior wall prolapse and increased intrarectal pressure. The resultant symptoms are
that of rectal evacuatory difficulty. Surgical treatment (abdominal rectopexy) is often unsatisfactory and
the first line management is biofeedback.
Scenario 2
4% Formalin (topical)
B - Fissure in ano « YOUR ANSWER
G - Radiation proctitis« CORRECT ANSWER.
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Dr Mohammed Shamsul Islam Khan, Medical Officer, Clinical Neuro-Surgery, National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh. Mobile: +880 1713 455 662, +880 1685 811979. E-mail: drsikhan@gmail.com
Page |
1543
MyPasTest: MRCS A Online - Jan Exam 2015
26. Surgical Specialities; General Surgery; Colorectal Surgery (36Qs)
G – Radiation proctitis:
Radiation proctitis following treatment for cervical or prostatic cancer is a troublesome condition that is
difficult to treat. Topical application of 4% formalin can help the bleeding. Other options include Nd: YAG
laser, and surgery in the form of a coloanal sleeve anastamosis.
Scenario 3
Insertion of seton
C - Low subcutaneous anal fistula (below the dentate line)« YOUR ANSWER
I - Transphincteric anal fistula« CORRECT ANSWER.
Treatment of anal fistula is complex when the tract extends high to involve a considerable portion of the
external anal sphincter. The danger of laying open too much external anal sphincter is to render the
patient incontinent. The difficulty in decision-making lies in estimating the ‘safe’ amount of sphincter to
divide and thus how much sphincter is left behind. The decision varies according to the sex of the patient,
the presence of sphincter defects, colonic and rectal function and also the patient. A low anal fistula,
below the dentate line is usually safe to lay open; however, if there is concern regarding continence a
seton (suture material: ethibond, nylon, silastic slings have all been used) can be placed through the tract
to allow drainage and reassessment of treatment options.
Scenario 4
2% Diltiazem ointment
D - Perianal abscess « YOUR ANSWER
B - Fissure in ano « CORRECT ANSWER.
B – Fissure in ano:
Diltiazem is a calcium antagonist that reduces the resting pressure of the internal anal sphincter muscle
(smooth muscle). Trials have shown this to be an effective treatment for acute and chronic anal fissures
(65% healing rates).
Scenario 5
Botulinum toxin
E - Perianal haematoma with supralevator extension« YOUR ANSWER
B - Fissure in ano « CORRECT ANSWER.
B – Fissure in ano:
Botulinum toxin has also been demonstrated to be an effective treatment for chronic anal fissure (73%
efficacy). The precise mechanism of action is unclear, but reduced myogenic tone and contractile
response to sympathetic stimulation by directly acting on its smooth muscle or indirectly on the nerves
through inhibition of acetylcholine release are possibilities.
05. A 27-year-old female presents with severe pain during defecation. She also reports a small amount of
blood on the toilet paper following defecation, and her only past medical history is constipation which
has become worse because of the pain. What is the most likely diagnosis? Select one answer only.
Anal fissure« YOUR ANSWER
Anal fistula
Haemorrhoids
Perianal abscess
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Dr Mohammed Shamsul Islam Khan, Medical Officer, Clinical Neuro-Surgery, National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh. Mobile: +880 1713 455 662, +880 1685 811979. E-mail: drsikhan@gmail.com
Page |
1544
MyPasTest: MRCS A Online - Jan Exam 2015
26. Surgical Specialities; General Surgery; Colorectal Surgery (36Qs)
Pilonidal sinus.
The history in the case is quite classical for an anal fissure where pain is the dominant symptom. In
haemorrhoids the patient often does not complain of any pain (unless strangulation of a prolapsed
haemorrhoid has occurred).
06. A 17-year-old male presents with right sided abdominal pain, which is worse on movement, and
anorexia. He is listed for an open appendicectomy which reveals a normal appendix. Further exploration
intra-operatively reveals a normal caecum, and a terminal ileum with no obvious inflammation. However,
an outpouching is noted on the terminal ileum around 60cm from the ileocaecal valve. What is the most
likely diagnosis? Select one answer only.
Abdominal TB« YOUR ANSWER
Appendicitis
Caecal carcinoma
Crohn’s disease
Meckel’s diverticulum« CORRECT ANSWER.
The normal appendix goes against a diagnosis of acute appendicitis. The normal caecum makes a caecal
tumour causes the symptoms very unlikely and the lack of inflammation in the terminal ileum makes
Crohn’s unlikely. The description of an outpouching in this location is consistent with a Meckel’s
diverticulum. These are embryological remnants of the vitello-intestinal duct and are a free diverticulum
of the terminal ileum. They occur in 2% of the population, are commonly 2 feet (60cm) from the ileocaecal
valve, often 2 inches (5cm) in length and twice as common in males. Acute inflammation of them may
mimic appendicitis and it is important when performing an appendicectomy to search for a Meckel’s
diverticulum if the appendix is normal.
07. Theme: Treatment of benign anorectal disorders
A Barrier cream
B Botulinum toxin injection
C Diltiazem ointment
D Drainage seton
E Fistulotomy
F Formaldehyde therapy
G Glycerol trinitrate ointment
H Haemorrhoidectomy
I Incision and drainage
J Injection sclerotherapy
K Lateral internal anal sphincterotomy
L Mapping excisional biopsy
M Prednisolone enema
N Rubber-band ligation.
The following patients have all presented with symptoms of an anorectal disorder. Please select the most
appropriate treatment from the above list. The items may be used once, more than once, or not at all.
Scenario 1
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Dr Mohammed Shamsul Islam Khan, Medical Officer, Clinical Neuro-Surgery, National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh. Mobile: +880 1713 455 662, +880 1685 811979. E-mail: drsikhan@gmail.com
Page |
1545
MyPasTest: MRCS A Online - Jan Exam 2015
26. Surgical Specialities; General Surgery; Colorectal Surgery (36Qs)
A 37-year-old man presents with a 6-month history of intermittent peri-anal pain and swelling followed by purulent
discharge; he is fully continent. A later examination under anaesthesia reveals a fistulous tract, commencing at
the dentate line, following an intersphincteric course.
A - Barrier cream« YOUR ANSWER
E - Fistulotomy« CORRECT ANSWER.
E – Fistulotomy:
This patient has an intersphincteric anal fistula. Successful surgical management of anal fistulae depends
upon accurate knowledge of anal sphincter anatomy and the fistula’s course through it; failure to
understand either may result in fistula recurrence or incontinence. This patient’s fistula is amenable to
fistulotomy (a procedure with a > 90% success rate), as it only encircles a proportion of the internal
sphincter muscle fibres which when laid open are unlikely to result in significant continence disturbance.
Scenario 2
A 19-year-old woman presents with a 2-month history of pain and fresh bleeding on defaecation; her past medical
history includes cluster headaches. Examination reveals a peri-anal sentinel skin tag at the <st1:time ">12 o’clock
position; proctoscopy cannot be performed because of patient discomfort.
B - Botulinum toxin injection« YOUR ANSWER
C - Diltiazem ointment« CORRECT ANSWER.
C – Diltiazem ointment:
This patient has an anal fissure the initial management of which is medical. 50–70% of patients who apply
0.2% glyceryl trinitrate ointment three times daily for 8 weeks have significant symptomatic
improvement/healing. Unfortunately, one of the side-effects is severe headaches which may result in poor
patient compliance. In this situation 2% diltiazem ointment, which is equally efficacious but more
expensive, is recommended.
Scenario 3
A 62-year-old woman presents 3 months after repeat injection sclerotherapy of haemorrhoids with an ongoing
history of passing fresh blood per rectum, and the sensation of a lump coming down which she manually reduces.
On examination, she has significant prolapsing haemorrhoids.
C - Diltiazem ointment« YOUR ANSWER
H - Haemorrhoidectomy« CORRECT ANSWER.
H – Haemorrhoidectomy:
Small internal (bleeding) or prolapsing haemorrhoids above the dentate line can be treated by injection
sclerotherapy or rubber-band ligation, respectively. Haemorrhoids refractory to non-operative therapy, or
those that are large and prolapsing with a significant external component usually require
haemorrhoidectomy. There are essentially two commonly used surgical options: Milligan and Morgan’s
sharp (now usually diathermy) excision and stapled haemorrhoidectomy (PPH). The patient should of
course be appraised of the risks before embarking on surgery.
08. Theme: Inherited Colonic Disease
A Peutz-Jeghers syndrome
B Hereditary haemorrhagic telangiectasia
C Familial Polyposis Coli
D Lynch Syndrome.
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Dr Mohammed Shamsul Islam Khan, Medical Officer, Clinical Neuro-Surgery, National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh. Mobile: +880 1713 455 662, +880 1685 811979. E-mail: drsikhan@gmail.com
Page |
1546
MyPasTest: MRCS A Online - Jan Exam 2015
26. Surgical Specialities; General Surgery; Colorectal Surgery (36Qs)
For the patients described below, select the single most likely diagnosis from the options listed above.
Each option may be used once, more than once, or not at all.
Scenario 1
A man presents with a 6-month history of lethargy and has had several blood transfusions. His blood profile is
normal. He has pigmented spots on lips and oral mucosa.
A - Peutz-Jeghers syndrome« CORRECT ANSWER.
This patient is most likely to have Peutz-Jeghers syndrome. Peutz-Jeghers syndrome is an autosomal
dominant disease which gives rise to hamartomatous polyps, characteristically in the small bowel. These
polyps can also be found in the stomach and colon.
Scenario 2
A 47-year-old man presents with rectal bleeding. His mother also had a similar condition and suffered from
ovarian cancer. There is a defect in the MSH2 gene.
B - Hereditary haemorrhagic telangiectasia« YOUR ANSWER
D - Lynch Syndrome« CORRECT ANSWER.
This is an autosomal dominantly inherited condition, hence the patient’s mother also had features. Lynch
Syndrome or Hereditary Nonpolyposis Colon Cancer (HNPCC) occurs due to variations in genes
associated with DNA repair including MSH2. There is an associated increase in stomach, small intestine,
gallbladder, skin, brain and ovarian cancer.
Scenario 3
An 18-year-old male attends with painless rectal bleeding. He has an APC gene defect.
C - Familial Polyposis Coli« CORRECT ANSWER.
This is an autosomal dominantly inherited condition in which mutations in the APC gene, a tumour
suppressor, leads to numerous colonic polyps. If left untreated these can undergo malignant change. P53
and KRAS mutations may also result in malignant change. If suspected or known family history then the
subject concerned may undergo a blood test to detect mutation in the APC gene. The patient will then
undergo colonoscopic surveillance.
09. Theme: Rectal bleeding
A Anal carcinoma
B Anal fissure
C Angiodysplasia
D Colonic carcinoma
E Colonic polyp
F Crohn’s disease
G Diverticular disease
H Haemorrhoids
I Infective colitis
J Ischaemic colitis
K Peri-anal haematoma
L Peptic ulceration
M Ulcerative colitis.
The following patients have all presented with rectal bleeding. Please select the most appropriate
diagnosis from the above list. The items may be used once, more than once, or not at all.
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Dr Mohammed Shamsul Islam Khan, Medical Officer, Clinical Neuro-Surgery, National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh. Mobile: +880 1713 455 662, +880 1685 811979. E-mail: drsikhan@gmail.com
Page |
1547
MyPasTest: MRCS A Online - Jan Exam 2015
26. Surgical Specialities; General Surgery; Colorectal Surgery (36Qs)
Scenario 1
A 61-year-old renal transplant patient is referred to you on-call with acute-onset severe bloody diarrhoea. He
appears clinically very unwell. He has no history of bowel problems.
A - Anal carcinoma« YOUR ANSWER
I - Infective colitis« CORRECT ANSWER.
I – Infective colitis:
Cytomegalovirus colitis can cause severe diarrhoea and torrential, even life-threatening, rectal bleeding.
This diagnosis should always be considered first in patients on immunosuppression. This and other
infections are common problems in acquired immune deficiency syndrome – other responsible
organisms include herpes virus, and Cryptosporidium.
Scenario 2
A 27-year-old woman is seen with a 3-day history of acute diarrhoea which she attributes to food-poisoning.
Today she has attended because of fresh rectal bleeding on the paper after wiping and once in the pan, separate
from the stool.
B - Anal fissure« YOUR ANSWER
H - Haemorrhoids« CORRECT ANSWER.
H – Haemorrhoids:
Bright-red rectal bleeding in a young patient is invariably the result of haemorrhoids. Such bleeding is
often triggered by trauma leading to ulceration of previously asymptomatic small piles. This can often be
confirmed on proctoscopy in the acute phase but quite often you see the patient in outpatients weeks or
months later when the problem has completely resolved. No further action need be taken.
Scenario 3
A 92-year-old woman presents with painless, bright-red rectal bleeding without other symptoms. Following a blood
transfusion a barium enema is performed, the result of which is normal, and she is sent back to the nursing home.
One week later, she rebleeds and returns to The Emergency Department. Again the bleeding settles, and after retransfusion, she undergoes a gastroscopy and colonoscopy at which no abnormality is detected.
C - Angiodysplasia« CORRECT ANSWER.
C – Angiodysplasia:
These are a type of arteriovenous malformation and are one of the common causes of significant lower
gastrointestinal bleeding in the elderly population. As in this case, it is notoriously difficult to pinpoint the
actual offending vessel. Where direct vision fails, mesenteric angiography or radionucleotide scans can
sometimes be of diagnostic use but often also yield negative results if the vessel is not actively bleeding
at the time of investigation. Should angiography demonstrate the source of bleeding, therapeutic
embolisation can be performed. In cases of continued bleeding with negative investigations, treatment
may involve total colectomy as a life-saving measure.
10. An 18-year-old female presents with intermittent abdominal pain and discomfort which is cramping in
nature and a feeling of bloating. The discomfort is often relieved through opening her bowels, and she
also reports intermittent episodes of diarrhoea, she denies any weight loss, rectal bleeding or mucous. A
colonoscopy is unremarkable. What is the most likely cause of her symptoms? Select one answer only.
Coeliac disease« YOUR ANSWER
Crohn’s disease
Irritable bowel syndrome« CORRECT ANSWER
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Dr Mohammed Shamsul Islam Khan, Medical Officer, Clinical Neuro-Surgery, National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh. Mobile: +880 1713 455 662, +880 1685 811979. E-mail: drsikhan@gmail.com
Page |
1548
MyPasTest: MRCS A Online - Jan Exam 2015
26. Surgical Specialities; General Surgery; Colorectal Surgery (36Qs)
Hiatus hernia
Ulcerative colitis.
Irritable bowel syndrome (IBS) is one of the commonest causes of abdominal pain and is a functional
disorder causing a mixture of pain, discomfort, bloating and altered bowel habit. It does not cause PR
bleeding or mucus, and these symptoms are suggestive of organic pathology and should be investigated
appropriately and not attributed to IBS. Investigations for IBS will show a normal rectum and colon, and
treatment focuses on symptomatic relief through dietary measures, antispasmodics and psychological
approaches.
11. A 78-year-old nursing home resident is admitted with severe diarrhoea and left iliac fossa pain. At
flexible sigmoidoscopy diffuse pseudomembranes are seen. Biopsy is neutrophil rich. What is the most
likely diagnosis? Single best answer - select one answer only.
Crohn’s Disease« YOUR ANSWER
Melanosis Coli
Malignancy
Pseudomembranous Colitis« CORRECT ANSWER
Ulcerative Colitis.
The appearance of pseudomembranes are typical for Pseudomembranous Colitis caused by the
Clostridum Difficle. This pathogen is more common in nursing home or hospitalised patients.
12. Theme: Rectal bleeding
A Crohn’s disease
B Familial adenomatous polyposis
C Fissure in ano
D Intussusception
E Meckel’s diverticulum
F Mid-gut volvulus
G Necrotising enterocolitis
H Solitary juvenile polyp.
For each of the clinical scenarios below, select the most likely cause of rectal bleeding from the above
list. Each option may be used once, more than once, or not at all.
Scenario 1
A 7-year-old girl presents with weight loss, abdominal pain and anaemia.
A - Crohn’s disease « CORRECT ANSWER.
Scenario 2
A 13-year-old boy presents with lower abdominal pain and shock.
B - Familial adenomatous polyposis « YOUR ANSWER
E - Meckel’s diverticulum« CORRECT ANSWER.
Scenario 3
A 3-year-old boy presents with painless bleeding, mixed with stool.
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Dr Mohammed Shamsul Islam Khan, Medical Officer, Clinical Neuro-Surgery, National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh. Mobile: +880 1713 455 662, +880 1685 811979. E-mail: drsikhan@gmail.com
Page |
1549
MyPasTest: MRCS A Online - Jan Exam 2015
26. Surgical Specialities; General Surgery; Colorectal Surgery (36Qs)
C - Fissure in ano « YOUR ANSWER
H - Solitary juvenile polyp« CORRECT ANSWER.
Scenario 4
A 16-year-old girl presents with painless bleeding, mixed with stool; her father died of colorectal cancer at the age
of 35 years.
D - Intussusception « YOUR ANSWER
B - Familial adenomatous polyposis « CORRECT ANSWER.
Scenario 5
A 1-month-old girl with recent intermittent bilestained vomiting has collapsed.
E - Meckel’s diverticulum« YOUR ANSWER
F - Mid-gut volvulus« CORRECT ANSWER.
Rectal bleeding is a common symptom throughout childhood. Crohn’s disease may present in many ways
but is frequently associated with weight loss or linear growth failure in children. Meckel’s diverticulum
may present with acute GI haemorrhage leading to the typical brick-red coloured stool. Ulceration is
caused by the ectopic gastric mucosa within the Meckel’s diverticulum and may also cause lower
abdominal pain. Solitary juvenile polyps are a relatively common cause of painless rectal bleeding.
Occasionally, juvenile polyps may be multiple. Familial adenomatous polyposis should be suspected in
children presenting with rectal bleeding when there is a family history of early colorectal carcinoma in
immediate family members. The polyps generally develop after puberty. Mid-gut volvulus is frequently
preceded by a history of intermittent colicky abdominal pain with or without bile-stained vomiting –
usually from the age of 3 months. This diagnosis should always be considered in a child with bile-stained
vomiting and rectal bleeding.
13. An 84-year-old male with multiple comorbidities presents with severe abdominal pain looking very
unwell. Blood gas reveals a severe metabolic acidosis and a CT scan confirms a diverticular perforation,
but the extent of abdominal contamination is unclear. A diagnostic laparoscopy is performed to assess if
the patient can avoid a laparotomy at present. This shows a purulent peritonitis, but no faecal
contamination. How would this be classified? Select one answer only.
Hinchey I« YOUR ANSWER
Hinchey II
Hinchey III« CORRECT ANSWER
Hinchey IV
Hinchey V.
The Hinchey classification is used for colonic perforation secondary to diverticular disease. It is divided
into four descriptions. Hinchey I describes localised (paracolic) abscesses, Hinchey II describes pelvic
abscesses, Hinchey III describes the presence of pus in the abdominal cavity (purulent peritonitis) as
described in this case. Hinchey IV describes faeculent peritonitis. It is sometimes possible forcases with
purulent peritonitis to be managed laparoscopically and through inserting a drain. It may then be possible
to perform the appropriate resection later as an elective procedure and stoma formation may not be
necessary.
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Dr Mohammed Shamsul Islam Khan, Medical Officer, Clinical Neuro-Surgery, National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh. Mobile: +880 1713 455 662, +880 1685 811979. E-mail: drsikhan@gmail.com
Page |
1550
MyPasTest: MRCS A Online - Jan Exam 2015
26. Surgical Specialities; General Surgery; Colorectal Surgery (36Qs)
14. Theme: Types of colitis
A Collagenous colitis
B Crohn’s colitis
C Diversion colitis
D Infective colitis
E Ischaemic colitis
F Lymphocytic colitis
G Pseudomembranous colitis
H Radiation colitis
I Ulcerative colitis.
The following patients have all been referred by their general practitioners with possible colitis. Please
select the most appropriate diagnosis from the above list. The items may be used once, more than once,
or not at all.
Scenario 1
A 47 year-old woman with long-standing diabetes is seen with a 6-month history of colicky lower abdominal pain
and watery diarrhoea. Her symptoms are intermittent; however, during ‘attacks’ she finds that she may open her
bowel up to seven times a day with the passage of watery diarrhoea. These episodes are associated with lower
abdominal pain and leave her feeling dehydrated and weak. So far she has had multiple blood tests, including
erythrocyte sedimentation rate and C-reactive protein, which are normal. A colonoscopy is arranged which
demonstrates a macroscopically normal looking colonic and terminal ileal mucosa. Mucosal biopsy reveals fibrotic
thickening of the of the subepithelial collagen layer.
A - Collagenous colitis« CORRECT ANSWER.
A – Collagenous colitis:
This is an uncommon form of colitis and is part of the disease spectrum termed microscopic colitis (the
other main subdivision is lymphocytic). It is most common among middle-aged women and there is an
association with autoimmune disorders such as coeliac disease, thyroid disorders, diabetes and
rheumatoid arthritis. Collagenous colitis (or ‘microscopic colitis’) syndrome is defined by the triad of
chronic watery diarrhoea, normal mucosal appearance on colonoscopy, and characteristic histological
changes in the mucosal biopsy. Note that when lymphocytic infiltration in the lamina propria is
significant, the disease may be termed lymphocytic colitis. When there is fibrotic thickening of the of the
subepithelial collagen layer, the disease may be termed ‘collagenous colitis’. No cure is yet available.
Treatment is directed at reducing inflammation and the symptoms of diarrhoea by means of drugs such
as sulphasalazine and mesalazine. Short courses of steroids may be required for severe cases.
Scenario 2
A 77-year-old man is seen in The Emergency Department with a 1-day history of sudden onset of severe lower
abdominal pain, vomiting and passage of bloody diarrhoea. On examination he is pyrexial (temperature 38°C),
tachycardic (pulse 105/min) and hypotensive (blood pressure 85/46 mmHg). He has severe left-sided tenderness
and guarding on abdominal examination.
B - Crohn’s colitis« YOUR ANSWER
E - Ischaemic colitis« CORRECT ANSWER.
E – Ischaemic colitis:
The case describes the classical triad of acute onset of abdominal pain, rectal bleeding and shock in an
elderly patient. The patient may have atrial fibrillation or another factor such as cardiac or liver disease.
Treatment involves resuscitation with intravenous fluids, blood and blood products before laparotomy, at
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Dr Mohammed Shamsul Islam Khan, Medical Officer, Clinical Neuro-Surgery, National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh. Mobile: +880 1713 455 662, +880 1685 811979. E-mail: drsikhan@gmail.com
Page |
1551
MyPasTest: MRCS A Online - Jan Exam 2015
26. Surgical Specialities; General Surgery; Colorectal Surgery (36Qs)
which the affected segment of bowel is resected. However, this may not be possible if the whole of the
mesenteric supply is affected (superior mesenteric occlusion with infarction of the small bowel and right
side of the colon).
Scenario 3
A 47-year-old man is referred for elective colectomy. You catch the end of the pathology discussion, which
concludes that he has DALMs (Dysplasia-associated lesion or mass).
C - Diversion colitis« YOUR ANSWER
I - Ulcerative colitis « CORRECT ANSWER.
I – Ulcerative colitis:
DALMs (dysplasia-associated lesion or mass) are polyps with surrounding dysplasia that can occur in
chronic ulcerative colitis. They are significant indicators of carcinoma elsewhere in the bowel or at least
its imminent development. They are therefore a strong indication for colectomy.
15. Theme: Fistula-in-ano (classification)
A Extrasphincteric
B High transsphincteric
C Intersphincteric
D Low transsphincteric
E Mid-transsphincteric
F Submucosal
G Suprasphincteric.
The following are descriptions of fistula-in-ano. Please select the most appropriate anatomical description
from the list. The items may be used once, more than once, or not at all.
Scenario 1
A 34-year-old man is undergoing an examination under anaesthesia for long-standing fistula-in ano. The operating
surgeon notes that the internal opening is at the level of the dentate line, with the fistula thence traversing both
sphincters to an external opening 4 cm fromthe anal verge.
A - Extrasphincteric« YOUR ANSWER
E - Mid-transsphincteric« CORRECT ANSWER.
E – Mid-transsphincteric:
Transsphincteric fistulae have a primary tract that passes through both sphincters at varying levels into
the ischiorectal fossa where they may lead to ischiorectal abscess formation. The fistula may be
described as high, mid- or low depending on where the fistula crosses the external sphincter, ie above, at,
or below the level of the dentate line respectively.
Scenario 2
A 42-year-old man is referred to the outpatient clinic for a 7-month history of recurrent peri-anal pain and swelling
followed by discharge of purulent fluid. Examination reveals a small opening, 1 cm from the anal verge. Palpation
of the surrounding tissue suggests an indurated tract, passing from the opening through the internal anal sphincter
to the dentate line. It does not seem to traverse the external anal sphincter.
B - High transsphincteric« YOUR ANSWER
C - Intersphincteric« CORRECT ANSWER.
C – Intersphincteric:
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Dr Mohammed Shamsul Islam Khan, Medical Officer, Clinical Neuro-Surgery, National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh. Mobile: +880 1713 455 662, +880 1685 811979. E-mail: drsikhan@gmail.com
Page |
1552
MyPasTest: MRCS A Online - Jan Exam 2015
26. Surgical Specialities; General Surgery; Colorectal Surgery (36Qs)
Sepsis having developed within the intersphincteric plane, it follows the path of least resistance down the
intersphincteric space, emerging at the peri-anal skin, resulting in an intersphincteric fistula (and often
presenting acutely as a peri-anal abscess).
Scenario 3
A 28-year-old woman with extensive peri-anal Crohn’s disease, continuously experiences peri-anal discharge of
sero-sanguinous fluid following drainage of an ischiorectal abscess. STIR-sequence magnetic resonance imaging
scans reveals a tract passing through the ischiorectal fossa and levator ani directly into the rectum.
C - Intersphincteric« YOUR ANSWER
A - Extrasphincteric« CORRECT ANSWER.
A – Extrasphincteric:
These rare fistulae run without relation to the sphincters and are classified according to their pathology.
They often originate from a segment of sigmoid diverticular disease or from ileal or sigmoid Crohn’s
disease. They can also be created by injudicious probing of peri-anal sepsis (iatrogenic).
Successful surgical management of anal fistulae depends upon accurate knowledge of anal sphincter
anatomy and the fistula’s course through it. Failure to understand either may result in fistula recurrence
or incontinence. The most comprehensive and practical classification is that devised by St Mark’s
Hospital. Sir Alan Parks’s cryptoglandular hypothesis (1976) is central, holding first that the majority of
fistulae arise from an abscess in the intersphincteric plane, and second that the relation of the primary
tract to the external sphincter is paramount in surgical management. The classic diagram of various
fistulae is a favourite of vivas where you might be asked to reproduce it.
16. A 32-year-old woman with a history of chronic diarrhoea undergoes a flexible sigmoidoscopy. There is
brownish discolouration on the wall of the sigmoid in a moire pattern. Biopsy reveals characteristic
pigment-laden macrophages within the mucosa on PAS staining. She works as a swimwear model and is
very concerned with her appearance. What is the most likely diagnosis? Single best answer - select one
answer only.
Crohn’s Disease« YOUR ANSWER
Campylobacter infection
Lymphoma
Melanosis Coli« CORRECT ANSWER
Ulcerative Colitis.
These features, both on endoscopy and histology, are typical of melanosis coli and typical of overuse of
laxatives. The appearance does not have any negative sequalae. She should be advised to stop abusing
laxatives. Note her occupation as a model suggesting she may feel pressurised to maintain her weight.
Offer psychological support if required.
17. Theme: Colorectal surgery
A Abdominoperineal resection
B Anterior resection
C Hartmann’s procedure
D Ileocolonic bypass
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Dr Mohammed Shamsul Islam Khan, Medical Officer, Clinical Neuro-Surgery, National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh. Mobile: +880 1713 455 662, +880 1685 811979. E-mail: drsikhan@gmail.com
Page |
1553
MyPasTest: MRCS A Online - Jan Exam 2015
26. Surgical Specialities; General Surgery; Colorectal Surgery (36Qs)
E Left hemicolectomy
F Panproctocolectomy
G Sigmoid colectomy and primary anastomosis
H Subtotal colectomy
I Transverse loop colostomy.
For each of the patients described below, select the most appropriate surgical option from the above list.
Each option may be used once, more than once, or not at all.
Scenario 1
A 55-year-old man reattends the surgical outpatient department with rectal bleeding. He has recently completed a
course of chemoradiotherapy for a squamous anal carcinoma. He underwent an examination under anaesthesia
(EUA) which revealed some residual tumour.
A - Abdominoperineal resection« CORRECT ANSWER.
A – Abdominoperineal resection:
The first case is of a man with a recurrence of his anal carcinoma. He has undergone chemoradiotherapy
which has failed. The only treatment for continued bleeding is surgery in the form of an abdominoperineal
resection.
Scenario 2
A 30-year-old woman with known ulcerative colitis is admitted as an emergency with abdominal distension,
vomiting, rectal bleeding and dehydration. She undergoes a course of conservative medical management but
does not respond to steroids and immunosuppressive therapy. Her albumin level is 20 g/l, WBC 25 x 10 9/l and her
colonic diameter on abdominal X-ray is 9 cm.
B - Anterior resection« YOUR ANSWER
H - Subtotal colectomy« CORRECT ANSWER.
H – Subtotal colectomy:
The second case is of a young woman with a flare-up of ulcerative colitis, failed medical treatment and
development of a toxic megacolon. The surgical option now is a subtotal colectomy with ileostomy, as
she is at imminent risk of perforation. The rectum is not excised, as this would increase the length of
surgery and increase her morbidity. In addition, as she is young the possibility of a future ileoanal pouch
should be left open to her.
Scenario 3
A 45-year-old man is admitted as an emergency to the Emergency Department with generalised peritonitis.
Following aggressive resuscitation he is taken to the operating theatre where a hard 4-cm mass is found in the
sigmoid colon. There is gross faecal contamination of the peritoneal cavity. His liver has one umbilicated nodule in
the left lobe. The rest of the laparotomy is normal.
C - Hartmann’s procedure« CORRECT ANSWER.
C – Hartmann’s procedure:
The third case is of a probable perforated sigmoid carcinoma and single metastasis to the liver. The
carcinoma should be resected. A primary anastomosis in the presence of gross faecal contamination
would be unwise. However, purulent peritonitis is itself not an absolute contraindication to a primary
anastomosis. This procedure should only be performed by an experienced surgeon and the majority
would cover with a loop ileostomy.
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Dr Mohammed Shamsul Islam Khan, Medical Officer, Clinical Neuro-Surgery, National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh. Mobile: +880 1713 455 662, +880 1685 811979. E-mail: drsikhan@gmail.com
Page |
1554
MyPasTest: MRCS A Online - Jan Exam 2015
26. Surgical Specialities; General Surgery; Colorectal Surgery (36Qs)
18. An 88-year-old female who has a past medical history of dementia and is bed bound in a nursing
home, presents with a history of constipation for the last 7 days. Her carers have noted her abdomen has
become grossly distended and is tender to touch. An abdominal X-ray demonstrates the coffee bean sign.
What would be an appropriate option to manage this patient initially? Select one answer only.
Antibiotics« YOUR ANSWER
CT scan
Exploratory laparotomy
Insertion of flatus tube« CORRECT ANSWER
Sigmoid colectomy.
The coffee bean sign and clinical history is highly suggestive of sigmoid volvulus which commonly
occurs in elderly patients who have a chronic history of constipation. Given the patient’s pre-morbid
status of being a bed bound nursing home patient, the risks of any major surgery e.g. laparotomy or
sigmoid colectomy would be great. A CT scan would confirm the diagnosis, but offers no therapeutic
benefit to the patient. Insertion of a flatus tube represents a relatively low risk procedure that could
potentially resolve the patient’s symptoms and therefore would be a good first line option.
19. An 89-year-old woman is seen on the post-take ward round following CT scanning. She presented with
tenderness in the left iliac fossa for 7 days. Bloods show raised inflammatory markers with a WCC of 18
and CRP 160. She has localised tenderness but is surprisingly well and feels better than on admission
yesterday. Past medical history reveals CVA 5 years ago which has left her bed bound and COPD
requiring multiple admissions. The CT scan shows diverticulitis with a localised perforation. What is the
best initial management? Single best answer - select one answer only.
Discharge« YOUR ANSWER
Intravenous antibiotics and close monitoring« CORRECT ANSWER
Laparotomy and primary anastomosis
Laparoscopic resection
Laxatives.
This elderly patient has localised diverticular perforation with absence of peritonitis and is showing signs
of improvement. Together with the fact that she has significant past medical history that would make her
a high risk candidate for surgery, therefore conservative management with IV antibiotics and close
monitoring for signs of deterioration is the best management path. If surgical intervention were required,
laparoscopy may be difficult due to her COPD. A primary anastomosis would not be advisable in an acute
case with potential contamination with a higher chance of anastomotic leak. An anastomotic leak could
be disastrous in this patient and so a colostomy would be best surgical practice. Laxatives are not the
primary concern in this patient's acute management, and discharge is obviously not appropriate at this
point.
20. An 82-year-old male presents with intermittent abdominal pain and vomiting. On further questioning it
is noted he has not opened his bowels for 5 days and not passed wind for 2 days. On examination he
looks uncomfortable and his abdomen is grossly distended. His only past medical history of note is an
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Dr Mohammed Shamsul Islam Khan, Medical Officer, Clinical Neuro-Surgery, National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh. Mobile: +880 1713 455 662, +880 1685 811979. E-mail: drsikhan@gmail.com
Page |
1555
MyPasTest: MRCS A Online - Jan Exam 2015
26. Surgical Specialities; General Surgery; Colorectal Surgery (36Qs)
open repair of an abdominal aortic aneurysm 4 months ago from which he recovered well. What is the
most likely cause of his symptoms? Select one answer only.
Adhesional small bowel obstruction« YOUR ANSWER
Aorto-enteric fistula
Incisional hernia
Diverticular disease
Sigmoid tumour.
This patient has a number of characteristic features of small bowel obstruction - vomiting, constipation
and abdominal distension. Adhesions are the most common cause of small bowel obstruction in the
developed world and can occur following any form of abdominal surgery. An aorto-enteric fistula would
classically cause PR bleeding, there is nothing in the history of the case to suggest the patient has an
incisional hernia which could be causing obstruction, and there are no features that point to diverticular
disease or a sigmoid tumour causing the symptoms.
21. Theme: Findings at laparotomy
A Colo-colic bypass procedure
B Right hemicolectomy
C Anterior resection
D Hartmann's procedure
E Defunctioning colostomy.
For each of the following situations, select the most likely answer from the above list. Each option may be
used once, more than once, or not at all.
Scenario 1
A 68-year-old man with a short history of generalised abdominal discomfort and pain with underlying weight loss
goes to laparotomy on the (N)CEPOD ((National) Confidential Enquiry into Patient Outcome and Death) list. He is
found to have a perforated tumour of the proximal sigmoid colon with faecal matter and fluid within the
peritoneum. No synchronous tumour or liver nodules are felt and chest X-ray pre-op is clear. The colon is mobile
A - Colo-colic bypass procedure« YOUR ANSWER
D - Hartmann's procedure« CORRECT ANSWER.
It is always tempting at the time in these cases to try a primary anastamoses. DO NOT. Faecal peritonitis
carries at least a 50% mortality, the patient is septic and even the most rigorous of washouts will not
ensure a safe environment for anastamosis. Resection with washout and fashioning of a colostomy is the
safest procedure, particularly as this patient is more amenable than most to a reversal in the future.
Scenario 2
A frail cachexic 84-year-old lady with a pre-operative ASA (American Society of Anaesthetists) grade of 3 is
reluctantly taken to theatre for colonic obstruction. The local CT (computerised tomography) scanner was broken
and she was deteriorating rapidly over the 24 h since admission. Exploratory laparotomy found a fungating tumour
at the hepatic flexure with collapsed bowel distal to it. Also, several suspicious nodules are felt on the liver
surface. Also, the anaesthetist is becoming concerned with her peri-operative progress
B - Right hemicolectomy« YOUR ANSWER
A - Colo-colic bypass procedure« CORRECT ANSWER.
Ideally a CT scan would have let you know what you were getting into, but this lady would still require
decompression. A right hemicolectomy would have been the plan, but findings of liver metastases makes
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Dr Mohammed Shamsul Islam Khan, Medical Officer, Clinical Neuro-Surgery, National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh. Mobile: +880 1713 455 662, +880 1685 811979. E-mail: drsikhan@gmail.com
Page |
1556
MyPasTest: MRCS A Online - Jan Exam 2015
26. Surgical Specialities; General Surgery; Colorectal Surgery (36Qs)
her prognosis much less favourable. She is unlikely to get another shot at surgery and the anaesthetist
will want the shortest and least complicated procedure possible. Mobilising hepatic flexure and
performing a right hemicolectomy will not improve prognosis. A bypass is a quick, easy and safe
palliative procedure. A defunctioning ileostomy is perhaps a second option.
Scenario 3
A 78-year-old female goes for a planned laparotomy for resection of a low rectal cancer. She has been staged by
CT 2 months before. The staging was at that time said to be T2N0M0. At laparotomy she was found to have
palpable liver masses and widespread peritoneal deposits. The tumour is annular and sizable to feel
C - Anterior resection« YOUR ANSWER
E - Defunctioning colostomy« CORRECT ANSWER.
Peritoneal deposits carry an awful prognosis. The risks of complications with low rectal tumours treated
by anterior resection would devastate the quality of life remaining in this lady. Defunctioning will be
palliative and prevent any obstruction in the future.
Scenario 4
An otherwise well 62-year-old lady with a T2N1M0 tumour at 8 cm from the anal margin is found to have a locally
palpable lymph node at laparotomy.
D - Hartmann's procedure« YOUR ANSWER
C - Anterior resection« CORRECT ANSWER.
The staging already tells us the patient has local adenopathy. The patient will most likely receive adjuvant
chemotherapy for this.
22. Theme: Abdominal surgery
A Sigmoid colectomy
B Abdomino-perineal excision of rectum (APR)
C Hartmann's procedure
D Sub-total colectomy and formation of ileostomy
E Right hemicolectomy
F Anterior resection of the rectum
G Left hemicolectomy.
From the list above, choose the most appropriate procedure for each of the following scenarios. Each
answer may be used once, more than once, or not at all.
Scenario 1
A 57-year-old man in good general health presents electively with bleeding per rectum, change in bowel habit and
iron deficiency anaemia. A caecal tumour has been confirmed on barium enema.
A - Sigmoid colectomy« YOUR ANSWER
E - Right hemicolectomy« CORRECT ANSWER.
This is the most appropriate procedure for a patient with a right-sided colonic tumour.
23. Theme: Rectal bleeding
A None
B rigid sigmoidoscopy
C Proctoscopy and rigid sigmoidoscopy
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Dr Mohammed Shamsul Islam Khan, Medical Officer, Clinical Neuro-Surgery, National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh. Mobile: +880 1713 455 662, +880 1685 811979. E-mail: drsikhan@gmail.com
Page |
1557
MyPasTest: MRCS A Online - Jan Exam 2015
26. Surgical Specialities; General Surgery; Colorectal Surgery (36Qs)
D rigid sigmoidoscopy and flexible sigmoidoscopy
E rigid sigmoidoscopy and colonoscopy.
From the list above, choose the most appropriate investigation(s) in addition to rectal examination, for the
following scenarios. Each answer may be used once, several times or not at all.
Scenario 1
A 35-year-old man who presents w ith a 3-month h istory of br ight red rectal bleed ing seen on the paper.
A - None« YOUR ANSWER
C - Proctoscopy and rigid sigmoidoscopy« CORRECT ANSWER.
Proctoscopy and rigid sigmoidoscopy:
This patient is relatively young and presents with common symptoms. This is likely to be associated with
haemorrhoidal bleeding which can be confirmed with proctoscopy and rigid sigmoidoscopy to exclude
any pathology in the upper rectum.
Scenario 2
A 55-year-old man seen in the outpatient clinic presents with 3 weeks of rectal bleeding. It is observed on
defaecation and is mixed with the stool His bowel habit is altered and his father died from colorectal carcinoma
aged 63 years.
B - rigid sigmoidoscopy« YOUR ANSWER
E - rigid sigmoidoscopy and colonoscopy« CORRECT ANSWER.
Rigid sigmoidoscopy and colonoscopy:
The concern in this scenario is of a malignant lesion, especially with a positive family history. He should
undergo urgent colonoscopy.
Scenario 3
A 26-year-old female who presents with a 6-week history of rectal bleeding. It is described as mixed with stool and
associated with diarrhoea. She has lost 5 kg in weight.
C - Proctoscopy and rigid sigmoidoscopy« YOUR ANSWER
E - rigid sigmoidoscopy and colonoscopy« CORRECT ANSWER.
Rigid sigmoidoscopy and colonoscopy:
In this case of is rectal bleeding, diarrhoea and weight loss inflammatory bowel disease (especially
ulcerative colitis) must be excluded. A colonoscopy will facilitate visualisation and biopsies of the entire
large bowel and also allow access to the terminal ileum (i.e. to exclude terminal ileal Crohn’s disease).
Scenario 4
A 32-year-old man with a 4-month history of small quantities of fresh rectal bleeding. The blood is seen on the
paper and he describes sharp pain on defaecation.
D - rigid sigmoidoscopy and flexible sigmoidoscopy« YOUR ANSWER
A - None« CORRECT ANSWER.
None:
The history here is very important as it should raise the suspicion of an anal fissure. In these cases it is
often not possible to perform a proctoscopy due to pain. Rectal examination will often reveal a sentinel
pile secondary to chronic fissuring. If possible, proctoscopy and rigid sigmoidoscopy should be
performed to exclude a more proximal cause, often general anaesthetic is needed for these to be done.
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Dr Mohammed Shamsul Islam Khan, Medical Officer, Clinical Neuro-Surgery, National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh. Mobile: +880 1713 455 662, +880 1685 811979. E-mail: drsikhan@gmail.com
Page |
1558
MyPasTest: MRCS A Online - Jan Exam 2015
26. Surgical Specialities; General Surgery; Colorectal Surgery (36Qs)
24. Theme: Investigation of disorders of the large intestine
A Abdominal radiograph
B Anorectal physiology
C Barium enema
D Colonoscopy
E Computed tomography scan of chest, abdomen and pelvis
F Examination under anaesthesia
G Flexible sigmoidoscopy
H Laparoscopy
I Laparotomy
J Mesenteric angiography
K Magnetic resonance imaging of pelvis
L Proctoscopy
M Water-soluble contrast enema
N Ultrasound scan of liver.
The following patients have all presented with disorders of the large intestine. Please select the next most
appropriate investigative step in the management. The items may be used once, more than once, or not at
all.
Scenario 1
A 52-year-old woman is seen in the outpatient department. She has no specific complaints herself but is worried
as her sister, who is 43-years-old, has been diagnosed with an adenocarcinoma of the sigmoid. There is no other
family history of note.
B - Anorectal physiology« YOUR ANSWER
D - Colonoscopy« CORRECT ANSWER.
D – Colonoscopy:
When assessing a patient’s risk of developing colorectal cancer (CRC), the family history is of paramount
importance. A family history of CRC in a first-degree relative is a significant finding and the age at which
the diagnosis was made is similarly of importance when quantifying a patient’s overall relative risk. So an
individual with a first-degree relative diagnosed with CRC earlier than age 55 years has a relative risk that
is two- to fivefold above that of individuals without a family history of CRC. In this case, the patient is
categorised as at moderate risk of developing CRC during her lifetime and as such this warrants
screening by colonoscopy.
Moderate risk is defined as having:
1. one first-degree relative affected by CRC before the age of 45 years
2. two (one aged less than 55 years) or three relatives at any age affected by CRC or endometrial
carcinoma who are first-degree relatives of each other and one a first-degree relative of the patient
3. two affected first-degree relatives (one aged less than 55 years).
Scenario 2
A 54-year-old man is seen in the clinic for follow-up. He initially presented with rectal bleeding. Proctoscopy and
rigid sigmoidoscopy performed at the time revealed a 1-cm benign-looking polyp, 15 cm from the anal verge,
which was biopsied. The histology report reads ‘fragments of a moderately dysplastic villous adenoma’.
C - Barium enema« YOUR ANSWER
D - Colonoscopy« CORRECT ANSWER.
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Dr Mohammed Shamsul Islam Khan, Medical Officer, Clinical Neuro-Surgery, National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh. Mobile: +880 1713 455 662, +880 1685 811979. E-mail: drsikhan@gmail.com
Page |
1559
MyPasTest: MRCS A Online - Jan Exam 2015
26. Surgical Specialities; General Surgery; Colorectal Surgery (36Qs)
D – Colonoscopy:
Complete examination of the colon is warranted as this patient is at a high risk of having synchronous
adenomatous polyps and/or colorectal carcinoma. This is on the basis of the findings of an adenomatous
polyp > 1 cm in diameter and villous histology. Other criteria include multiple (more than two) adenomas
and adenomas with high-grade dysplasia. The incidence of a synchronous lesion in such a case is of the
order of 2%. Such lesions may be detected by barium enema examination; however, colonoscopy has the
advantage of allowing endoscopic polypectomy to be performed. So it is not only diagnostic, but also
therapeutic. Further follow-up colonoscopy timings are outlined in the British Society of Gastroenterology
(BSG) guidelines and depend on the findings.
Scenario 3
An 86-year-old woman is admitted to hospital with a history of sudden onset of severe rectal bleeding. She has
been resuscitated but continues to bleed. An OGD has been performed, which is normal, and a colonoscopy is
performed which demonstrates the presence of a large volume of blood in the lumen of the bowel. The
endoscopist is unable to define the source of bleeding because of the view being obscured by active bleeding
which could not be aspirated. She is currently stable, blood pressure 120/65 mmHg, pulse 85/min, and is
receiving her fifth unit of blood.
D - Colonoscopy« YOUR ANSWER
J - Mesenteric angiography« CORRECT ANSWER.
J – Mesenteric angiography:
Mesenteric angiography is the logical next step in the management of a patient in whom colonoscopy has
failed to detect the source of bleeding. This is of particular importance in an elderly patient who has
evidence of significant ongoing bleeding, but who is cardiovascularly stable. Angiography relies on active
bleeding for diagnosis, following which therapeutic embolisation of the offending vessel may be
performed. Should the investigation fail to demonstrate the cause, and the patient continue to bleed, then
laparotomy and colectomy may be necessary as a life-saving procedure.
Scenario 4
A 49-year-old man is referred with a history of weight loss and anaemia. He has undergone a flexible
sigmoidoscopy, which demonstrated a friable, annular constricting tumour in the descending colon. The
endoscopist was unable to examine the colon proximal to this lesion. The histology, from biopsies taken,
demonstrates adenocarcinoma.
E - Computed tomography scan of chest, abdomen and pelvis« CORRECT ANSWER.
E – Computed tomography (CT) scan of chest, abdomen and pelvis:
This patient has beeen diagnosed with colorectal carcinoma and as such the next step is to stage the
disease process. This requires imaging of the liver and chest for metastatic disease. Isolated ultrasound
scanning of the liver is insufficient and in fact the use of CT is recommended in national cancer services
guidelines. Were the tumour to be rectal, magnetic resonance imaging of the pelvis should also be
performed for local ‘T’ staging.
Scenario 5
A 63-year-old man is seen in The Emergency Department with a 4-day history of colicky lower abdominal pain,
absolute constipation and distension. On direct questioning he admits to recent weight loss and rectal bleeding.
On examination his abdomen is distended but soft. Plain radiography demonstrates large bowel distension.
F - Examination under anaesthesia« YOUR ANSWER
M - Water-soluble contrast enema« CORRECT ANSWER.
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Dr Mohammed Shamsul Islam Khan, Medical Officer, Clinical Neuro-Surgery, National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh. Mobile: +880 1713 455 662, +880 1685 811979. E-mail: drsikhan@gmail.com
Page |
1560
MyPasTest: MRCS A Online - Jan Exam 2015
26. Surgical Specialities; General Surgery; Colorectal Surgery (36Qs)
M – Water-soluble contrast enema:
Although the vignette strongly points to malignant large bowel obstruction, and a laparotomy will almost
certainly, therefore, be required, it is imperative to exclude pseudo-obstruction before risking a potentially
unnecessary laparotomy. This can be achieved by an enema or by computed tomography scan with rectal
contrast. In modern practice, it may also identify whether a stent can be deployed, especially in unfit
elderly patients.
25. Theme: Faecal incontinence
A Colorectal carcinoma
B Dementia
C Extra-rectal or rectovaginal fistula
D Faecal impaction
E Inflammatory bowel disease
F Pudendal neuropathy
G Sphincter disruption
H Spinal cord lesion
I Systemic neuropathology.
The following patients have all presented with faecal incontinence. From the above list choose the most
appropriate cause. Each item may be used once, more than once, or not at all.
Scenario 1
A 26-year-old woman is referred from her general practitioner with passive faecal incontinence following the birth
of her child 3 months ago.
A - Colorectal carcinoma« YOUR ANSWER
G - Sphincter disruption« CORRECT ANSWER.
G – Sphincter disruption:
Obstetric trauma frequently results in a transient degree of faecal incontinence in the immediate postpartum period in up to a third of women but this incontinence subsequently improves. This is related to
traction of the sphincteric complex and the pudendal nerve. An alarming proportion of women sustain
occult sphincteric damage and evidence suggests that many third-degree tears (extending from perineum
to involve the anal sphincter complex) are inadequately repaired.
Scenario 2
A 68-year-old man presents with new onset of faecal incontinence. He has been previously fit and well but now
describes passing loose stools with an increased frequency.
B - Dementia« YOUR ANSWER
A - Colorectal carcinoma« CORRECT ANSWER.
A – Colorectal carcinoma:
In this case the ‘passenger’ is responsible for causing faecal incontinence. This scenario highlights the
importance of excluding all organic pathology in a patient who has few other symptoms indicating that
they have a carcinoma. Any new symptoms or change in bowel habit in a patient over 45 years old should
prompt thorough examination and investigation, before assessing for a functional pathology.
Scenario 3
A 60-year-old woman with four children presents with a 3-year history of worsening urge faecal incontinence. She
had two prolonged, instrumented deliveries.
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Dr Mohammed Shamsul Islam Khan, Medical Officer, Clinical Neuro-Surgery, National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh. Mobile: +880 1713 455 662, +880 1685 811979. E-mail: drsikhan@gmail.com
Page |
1561
MyPasTest: MRCS A Online - Jan Exam 2015
26. Surgical Specialities; General Surgery; Colorectal Surgery (36Qs)
C - Extra-rectal or rectovaginal fistula« YOUR ANSWER
F - Pudendal neuropathy« CORRECT ANSWER.
F – Pudendal neuropathy:
Multiple, traumatic vaginal deliveries will result in a stretch injury to the pudendal nerve. This results in a
weakness in the external anal sphincter, causing attenuated squeeze pressure. Patients subsequently
complain of an inability to defer defaecation (urgency) with incontinence. This lady might benefit from a
low-dose of amitryptiline, which has been demonstrated to reduce rectal sensitivity, and biofeedback. In
the absence of a discrete sphincteric lesion, there are few surgical procedures that have sustained
benefit. In extreme cases, a colostomy may be the only option available to such patients.
The aetiology of faecal incontinence should be thought of as a disturbance to the passage or passenger.
The ‘passage’ consists of the rectum, which stores and expels faeces when appropriate, and the anal
canal which is composed of two rings of muscle (the internal and external anal sphincter) that relax to
allow emptying. The pudenal nerve is a mixed nerve that provides motor function to the external anal
sphincter, as well as sensation to the anal canal providing sensory input that forms part of a ‘sampling
reflex’. The ‘passenger’ or faeces, if loose, will frequently result in incontinence even in the presence of a
normally functioning anorectal sphincteric complex (as anyone who has experienced severe dysentery
would know). Alternatively, sphincteric disruption may lead to incontinence even for normal stool.
26. A frail 87-year-old female is brought in by her concerned family as she has started vomiting and not
opened her bowels or passed wind for 3 days. On examination she looks poorly with a distended
abdomen, but no previous incisions, and on further questioning she reports the pain radiates along the
right upper medial thigh. Vaginal examination reveals a swelling in the right side wall of the vagina. What
is the most likely diagnosis? Select one answer only.
Adhesional small bowel obstruction« YOUR ANSWER
Epigastrichernia
Para-umbical hernia
Obturator hernia« CORRECT ANSWER
Sigmoid volvulus.
Although the most common cause of small bowel obstruction is adhesions in the developed world, the
lack of previous surgery makes this very unlikely. The pain radiates to the thigh is suggestive of pressure
on the obturator nerve which supplies sensation to the medial thigh. This can be present in around 50%
of patients with an obturator hernia. Obturator hernias occur most commonly in frail old women and often
there are no signs. If pressure is present over the obturator nerve patients often hold the leg flexed to
reduce pain. Rectal and more often vaginal examination can reveal a swelling in the region of the
obturator foramen.
27. Theme: Stomas
A End ileostomy
B Loop ileostomy
C End colostomy
D Loop colostomy
E End colostomy and mucus fistula.
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Dr Mohammed Shamsul Islam Khan, Medical Officer, Clinical Neuro-Surgery, National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh. Mobile: +880 1713 455 662, +880 1685 811979. E-mail: drsikhan@gmail.com
Page |
1562
MyPasTest: MRCS A Online - Jan Exam 2015
26. Surgical Specialities; General Surgery; Colorectal Surgery (36Qs)
From the list above, choose the most appropriate stoma for the following scenarios. Each answer may be
used once, several times or not at all.
Scenario 1
A 74-year-old man undergoes an elective abdomino-perineal resection of a lower-third rectal carcinoma
A - End ileostomy« YOUR ANSWER
C - End colostomy« CORRECT ANSWER.
Lower-third rectal tumours require an abdomino-perineal resection. This is a major procedure that leaves
the patient with a permanent end colostomy sited in the left iliac fossa.
Scenario 2
A 36-year-old woman with known ulcerative colitis presents as an emergency with abdominal pain and profuse
bloody diarrhoea. Plain abdominal X-ray is indicative of a toxic megacolon
B - Loop ileostomy« YOUR ANSWER
A - End ileostomy« CORRECT ANSWER.
This patient is presenting with an acute and severe exacerbation of ulcerative colitis. The presence of a
toxic megacolon indicates the need for urgent surgery in the form of a subtotal colectomy and formation
of end ileostomy. Dependent upon her recovery it may be possible to perform an ileo-rectal anastamosis
at a later point.
Scenario 3
A 58-year-old man undergoes an elective anterior resection of the rectum for a confirmed middle-third rectal
carcinoma. The anastamosis is constructed with a stapling device given its relatively low position.
C - End colostomy« YOUR ANSWER
B - Loop ileostomy« CORRECT ANSWER.
Patients who undergo resection of relatively low tumours may require a temporary loop ileostomy,
commonly in the right iliac fossa. This is constructed to protect the low-lying anastamosis. It can be
reversed after approximately 6 weeks, providing that the anastamosis is satisfactory, usually confirmed
via a contrast enema.
Although a loop colostomy may also serve the purpose of defunctioning the distal anastomosis, it is
technically more challenging and associated with a higher risk of parastomal herniation. It is slightly less
commonly performed than the loop ileostomy for this purpose, although practice varies geographically.
Scenario 4
A 69-year-old man has a confirmed upper-third rectal carcinoma. He is scheduled for pre-operative radiotherapy
in an attempt to downsize the tumour and make surgery more feasible.
D - Loop colostomy« CORRECT ANSWER.
Patients who have large tumours that are not immediately resectable may be suitable for pre-operative
radiotherapy to downsize the lesion. In this case they require a loop colostomy to divert the faecal stream.
This is commonly performed at the transverse or sigmoid colon.
28. Theme: Diseases of the anus
A Anal carcinoma
B Anal intra-epithelial neoplasia
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Dr Mohammed Shamsul Islam Khan, Medical Officer, Clinical Neuro-Surgery, National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh. Mobile: +880 1713 455 662, +880 1685 811979. E-mail: drsikhan@gmail.com
Page |
1563
MyPasTest: MRCS A Online - Jan Exam 2015
26. Surgical Specialities; General Surgery; Colorectal Surgery (36Qs)
C Anal fissure
D Anal fistula
E Condylomata acuminata
F Fibroepithelial anal polyp
G Haemorrhoids
H Peri-anal abscess
I Peri-anal haematoma
J Pilonidal abscess
K Proctalgia fugax
L Skin tags
M Solitary rectal ulcer syndrome.
The following are descriptions of local anorectal disorders. Please select the most appropriate diagnosis
from the list. The items may be used once, more than once, or not at all.
Scenario 1
A 24-year-old man presents with a 3-month history of pain and passage of fresh blood on defaecation.
Examination reveals a small skin tag at the anal verge; attempted proctoscopy has to be abandoned because of
patient discomfort.
A - Anal carcinoma« YOUR ANSWER
C - Anal fissure« CORRECT ANSWER.
C – Anal fissure:
This is the typical presentation of this condition.
Scenario 2
A condition associated with chronic infection with human papillomavirus (especially serotypes 16 and 18).
B - Anal intra-epithelial neoplasia« YOUR ANSWER
A - Anal carcinoma« CORRECT ANSWER.
A - Anal Carcinoma:
Infection with human papillomavirus can lead to anal warts and dysplastic changes within the anal
epithelium (mild to severe: termed anal epithelial neoplasia). These may progress to anal carcinoma. So
patients with warts and those with other sexually transmitted diseases affecting the anus should have
biopsies and possibly thence surveillance if required. Other possible diagnoses could be B - Anal intraepithelial neoplasia, or E - Condylomata acuminata however Anal carcinoma is the most likely.
Scenario 3
A 31-year-old man presents with a 1-year history of severe anal pain lasting for 2 to 3 minutes each night. Per
rectum and proctosigmoidoscopic examinations are unremarkable.
C - Anal fissure« YOUR ANSWER
K - Proctalgia fugax« CORRECT ANSWER.
K – Proctalgia fugax:
This is defined as episodic, intense anal pain of short duration (usually at night) in which all other
disorders have been excluded. Proctalgia fugax occurs in up to 18% of the US population, being more
common in men, and those < 40 years old. It is thought to be secondary to sensory dysfunction, with
possible hypersensitivity of the internal anal sphincter and rectal musculature, precipitated by
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Dr Mohammed Shamsul Islam Khan, Medical Officer, Clinical Neuro-Surgery, National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh. Mobile: +880 1713 455 662, +880 1685 811979. E-mail: drsikhan@gmail.com
Page |
1564
MyPasTest: MRCS A Online - Jan Exam 2015
26. Surgical Specialities; General Surgery; Colorectal Surgery (36Qs)
psychological stress. Treatment can be problematic with many systemic (eg antidepressants) and local
(eg glyceryl trinitrate) remedies tried.
29. Theme: Abdominal system investigations
A Barium enema
B Colonoscopy
C CT
D Endoanal ultrasound
E Evacuation proctogram enema
F Flexible sigmoidoscopy
G MRI
H Red cell scan
I Single contrast gastrografin.
For each of the following scenarios, select the most likely answer from the above list. Each option may be
used once, more than once, or not at all.
Scenario 1
Family history of colonic cancer: brother (aged 35 years), sister (aged 32 years) and father (aged 60 years).
A - Barium enema « YOUR ANSWER
B - Colonoscopy « CORRECT ANSWER.
B – Colonoscopy:
Screening of colonic cancer in patients with a positive family history should be performed with
colonoscopy as the whole colon must be visualised. The use of computed tomography (CT) colonography
and magnetic resonance (MR) colonography for screening and primary detection of colorectal cancers is
the subject of ongoing research.
Scenario 2
A frail 88-year-old lady with multiple medical comorbidities and a change in bowel habit.
B - Colonoscopy « YOUR ANSWER
C - CT « CORRECT ANSWER.
C – CT:
The problem here is the age of the patient and whether they would be able to tolerate a colonoscopy or
barium enema investigation. It is common practice in many centres to use CT to identify a primary
colorectal cancer in the over 80-year age group.
Scenario 3
A 25-year-old man with bright red rectal bleeding.
C - CT « YOUR ANSWER
F - Flexible sigmoidoscopy« CORRECT ANSWER.
F – Flexible sigmoidoscopy:
Bright red rectal bleeding in a young patient with no change in bowel habit can be suitably investigated
with flexible sigmoidoscopy, as it is most likely that the source is located in the left colon.
Scenario 4
Angiodysplasia of the colon.
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Dr Mohammed Shamsul Islam Khan, Medical Officer, Clinical Neuro-Surgery, National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh. Mobile: +880 1713 455 662, +880 1685 811979. E-mail: drsikhan@gmail.com
Page |
1565
MyPasTest: MRCS A Online - Jan Exam 2015
26. Surgical Specialities; General Surgery; Colorectal Surgery (36Qs)
D - Endoanal ultrasound « YOUR ANSWER
B - Colonoscopy « CORRECT ANSWER.
B – Colonoscopy:
Angiodysplasia of the colon is most commonly located in the ascending colon and caecum and is
therefore best visualised by colonoscopy. Mesenteric angiography can also be used to demonstrate this
vascular malformation. The malformations consist of dilated tortuous submucosal veins that may be
replaced by massive dilated vessels in severe cases.
30. An 85-year-old male is recovering 2 days after a hemiarthroplasty for a fractured neck of femur. The
nurses call you as he has started vomiting profusely and his abdomen is distended. He has not opened
his bowels for 3 days and on examination he has a distended, tender abdomen. He has never undergone
any abdominal surgery and has no palpable herniae. His rectum is empty. His blood tests show a
potassium of 2.6, creatinine of 144. What is the most likely diagnosis? Select one answer only.
Adhesional small bowel obstruction« YOUR ANSWER
Constipation secondary to opioids
Incisional hernia
Obstruction hernia
Pseudo-obstruction« CORRECT ANSWER.
The history of vomiting, constipation and a distended abdomen are suggestive of an obstruction.
However, the most common cause for small bowel obstruction namely adhesions and herniae are unlikely
in the case given the patient has never had abdominal surgery and has no palpable herniae respectively.
His empty rectum points away from constipation. In this case this gentleman has developed pseudoobstruction which often resembles bowel obstruction and can occur in any post-op patients and can also
be triggered by deranged electrolytes e.g. hypokalaemia. It is best managed conservatively through
correcting the underlying causes.
31. A 35-year-old male presents after being referred from the GP with a painful swelling which is
discharging around his anus. He has had a similar problem twice in the past and on examination a very
tender, erythematous swelling is noted in the natal cleft, but separate from the anal verge. What is the
most likely diagnosis? Select one answer only.
Ischiorectal abscess« YOUR ANSWER
Hidradenitissuppurativa
Perianal abscess
Pilonidal abscess« CORRECT ANSWER
Supralevator abscess.
The commonest site for pilonidal abscesses is the natal cleft and there may be a history of recurrent
episodes over months or years. Pilonidal means ‘hair’s nest’ in Latin and theories regarding its aetiology
involve shed hairs getting trapped in pits and becoming a nidus for local infection. Clinically there may be
openings in the midline or either side of it sometimes with tufts of hair. There may be inflammation of the
adjacent skin and pus may be expressed via the openings. Management involves incision and drainage of
the abscess and then other procedures can be done electively to try and prevent recurrence.
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Dr Mohammed Shamsul Islam Khan, Medical Officer, Clinical Neuro-Surgery, National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh. Mobile: +880 1713 455 662, +880 1685 811979. E-mail: drsikhan@gmail.com
Page |
1566
MyPasTest: MRCS A Online - Jan Exam 2015
26. Surgical Specialities; General Surgery; Colorectal Surgery (36Qs)
32. Theme: Constipation
A Colorectal carcinoma
B Constipation-predominant irritable bowel syndrome
C Diabetes mellitus constipation
D Eating disorders
E Functional faecal retention
F Hirschsprung’s disease
G Hypercalcaemia
H Hypothyroidism
I Iatrogenic drug therapy
J Idiopathic megabowel
K Idiopathic ‘slow-transit’
L Neurogenic constipation
M Pelvic nerve injury
N Outlet obstruction
O Severe depression
P Simple constipation.
The following patients all present with constipation. From the list above, select the most likely diagnosis.
The items may be used once, more than once, or not at all.
Scenario 1
A 53-year-old woman presents with a 2-year history of increasing difficulty passing stool. She currently opens her
bowels daily or on alternate days. However, she has to strain excessively and often has to press on her perineum
to achieve evacuation. She also reports a ‘bulge’ in the vagina when she gets constipated. She has attended clinic
for the results of her recent investigations. Blood investigations and colonoscopy were normal.
A - Colorectal carcinoma « YOUR ANSWER
N - Outlet obstruction« CORRECT ANSWER.
N – Outlet obstruction:
This patient has ‘functional constipation’, because investigations have excluded an organic cause.
Constipation may refer to the infrequent and/or difficult passage of stools. A predominance of symptoms
of difficult evacuation, which is often referred to as obstructed defaecation (eg excessive straining, a
sensation of incomplete evacuation, digitation etc) is suggestive of outlet obstruction, rather than slow
transit constipation, although physiological confirmation is required as symptoms do not accurately
predict underlying pathophysiology. The history of perineal massage and a ‘bulge’ in the vagina
(posterior wall) is suggestive of the presence of a rectocoele, which may lead to outlet obstruction, as a
result of redistribution of evacuatory forces during defaecation.
Scenario 2
A 74-year-old man presents to the surgical clinic with a 2-month history of constipation. Previously, he opened his
bowels daily, passing stool of ‘normal’ consistency, but his bowels have become irregular, and he has
experienced episodes of ‘diarrhoea’ during the last few weeks. On direct questioning, he reported episodic fresh
bleeding per rectum, which he attributed to his ‘piles’.
B - Constipation-predominant irritable bowel syndrome« YOUR ANSWER
A - Colorectal carcinoma « CORRECT ANSWER.
A – Colorectal carcinoma:
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Dr Mohammed Shamsul Islam Khan, Medical Officer, Clinical Neuro-Surgery, National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh. Mobile: +880 1713 455 662, +880 1685 811979. E-mail: drsikhan@gmail.com
Page |
1567
MyPasTest: MRCS A Online - Jan Exam 2015
26. Surgical Specialities; General Surgery; Colorectal Surgery (36Qs)
This diagnosis must always be excluded in patients presenting with altered bowel habit. It is now clear
that most patients with colorectal cancer who present with altered bowel habit report loose stools or
diarrhoea. This represents ‘overflow’ of proximal bowel content because of narrowing of the lumen in the
affected segment of bowel. Careful history taking often reveals a period of constipation preceding the
change in stool consistency. It is unwise to attribute potentially sinister symptoms (eg bleeding per
rectum) to ‘benign’ pathology (eg haemorrhoids) until proximal pathology has been excluded.
Scenario 3
A 22-year-old man with a history of constipation since early childhood attends The Emergency Department having
not opened his bowels for the previous 3 weeks. He was admitted with similar symptoms several months ago,
when a rectal biopsy was performed. This demonstrated normal ganglion cells in the myenteric plexus, and no
other abnormality. On examination he appears well. Abdominal examination reveals a large mass arising in the
pelvis and extending to the umbilicus.
C - Diabetes mellitus constipation« YOUR ANSWER
J - Idiopathic megabowel« CORRECT ANSWER.
J – Idiopathic megabowel:
Persistent dilatation of the bowel is known as megabowel. This may occur secondary to an absence of
ganglion cells in the myenteric plexus (Hirschsprung disease), where failure of relaxation of the affected
segment leads to gross proximal dilatation. Alternatively, no obvious cause may be identifiable, when it is
termed idiopathic megabowel. This condition is characterised by severe infrequency of defaecation, with
several weeks between bowel movements. There is usually associated passive leakage of stool as a
result of ‘overflow’ around impacted stool in the rectum. The diagnosis is confirmed on barium enema,
which reveals dilatation of the rectum, and sometimes colon. Management involves behavioural, medical
and, rarely, surgical treatment.
Constipation is the second most common gastrointestinal symptom in the developed world. In most
patients, low fluid intake, low dietary fibre, and lack of exercise or mobility may contribute to ‘simple’
constipation. However, constipation may be caused by ‘organic’ pathology when it occurs secondary to
structural or systemic abnormalities. Organic causes may affect the gastrointestinal tract itself, eg
mechanical obstruction secondary to carcinoma/stricture, and persistent dilatation of the bowel
(megabowel) occurring without obvious cause (idiopathic) or secondary to Hirschsprung disease.
Extragastrointestinal pathology may also cause constipation. Examples include endocrine/metabolic,
neurological and psychological disorders.
Constipation may also occur secondary to certain medication (opiates, antidepressants, anticholinergics,
anticonvulsants). In the absence of an organic cause for constipation, the term ‘functional’ constipation is
adopted to indicate disordered function of the hindgut. On the basis of physiological investigations, such
patients may be divided into those with a delay in transit through all or part of the colon (slow transit
constipation), and/or those with abnormalities of rectal evacuation (outlet obstruction) or those with no
abnormality (constipation-predominant irritable bowel syndrome). The causes in the list provided may be
classified using this system to provide a comprehensive differential diagnosis for constipation.
33. A 56-year-old man undergoes an anterior resection. The resection specimen shows invasion beyond
the muscularis propria but no nodal involvement. What is his 5 year survival according to Dukes’ stage?
Single best answer - select one answer only.
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Dr Mohammed Shamsul Islam Khan, Medical Officer, Clinical Neuro-Surgery, National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh. Mobile: +880 1713 455 662, +880 1685 811979. E-mail: drsikhan@gmail.com
Page |
1568
MyPasTest: MRCS A Online - Jan Exam 2015
26. Surgical Specialities; General Surgery; Colorectal Surgery (36Qs)
6%« YOUR ANSWER
47%
77%« CORRECT ANSWER
93%
100%.
This patient has Dukes’ stage B colon cancer defined by invasion into the muscularis propria but not
beyond to involve lymph nodes on the histology specimen. This equates to a 5 year survival of 77%.
Dukes' staging (A-D) is still in common usage as an adjunct to TNM staging in determining the
management of colorectal cancer.
Stage
Description
5 year survival %
A
Confined to bowel wall
93.2%
B
Through bowel wall - Lymph node not involved
77%
C
Lymph nodes involved, no other metastases
47.7%
D
Distant metastases
6.6%
(figures from Cancer Research UK - 2012)
34. A 65-year-old male undergoes an emergency laparotomy for large bowel obstruction. This reveals an
obstructing sigmoid tumour. This is resected and a Hartmanns’ procedure is completed. Histology for the
specimen reveals the tumour has extended through all the muscle layers, but no lymph node involvement
is noted. What Dukes’ stage would this tumour be classified as? Select one answer only.
Stage A« YOUR ANSWER
Stage B« CORRECT ANSWER
Stage C
Stage D
Stage E.
The Dukes’ system is one of the most well-known staging methods for colonic carcinoma.





Stage A- Neoplastic cells are restricted to the mucosa and the 5 year survival is 90%.
Stage B- The tumour has extended through the muscle layers and possibly reached the serosa.
Lymph node involvement is not present though and the 5 year survival is 75%.
Stage C- This occurs where lymph node involvement is present and can be subdivided into
 C1 (local lymph node involvement only) and
 C2 (more proximal lymph node involvement). The overall survival is around 50%.
Stage D- This wasn’t part of the original description, but is often used to describe widespread
malignant disease. The 5 year survival is 6%.
There is no such stage as E.
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Dr Mohammed Shamsul Islam Khan, Medical Officer, Clinical Neuro-Surgery, National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh. Mobile: +880 1713 455 662, +880 1685 811979. E-mail: drsikhan@gmail.com
Page |
1569
MyPasTest: MRCS A Online - Jan Exam 2015
26. Surgical Specialities; General Surgery; Colorectal Surgery (36Qs)
35. A 65-year-old woman presents with a change in bowel habit. She has had fresh bloody diarrhoea for
the last 2 months. Flexible sigmoidoscopy revealed inflamed and ulcerated mucosa from the rectum to as
high as the scope could extend in the splenic flexure. Biopsy shows superficial ulceration and diffuse
mucosal inflammation. What is the likely diagnosis? Single best answer - select one answer only.
Crohn’s Disease« YOUR ANSWER
Ischaemic Colitis
Lymphoma
Salmonella Infection
Ulcerative Colitis« CORRECT ANSWER.
This patient has ulcerative colitis as evident in history, endoscopy findings with confluent inflammation,
and histology results. This inflammatory disorder differs from Crohn’s Disease as granulomas are absent,
fissures are rare and inflammation is superficial involving the mucosal layer.
36. Theme: Rectal bleeding
A Anal carcinoma
B Anal fissure
C Angiodysplasia
D Colonic carcinoma
E Colonic polyp
F Crohn’s disease
G Diverticular disease
H Haemorrhoids
I Infective colitis
J Ischaemic colitis
K Ulcerative colitis.
For each of the following scenarios, select the most likely answer from the above list. Each option may be
used once, more than once, or not at all.
Scenario 1
A 20-year-old lady presents with a 3-week history of bright red rectal bleeding associated with pain on
defaecation. Her symptoms started post-partum.
A - Anal carcinoma « YOUR ANSWER
B - Anal fissure « CORRECT ANSWER.
B – Anal fissure:
Pain on defaecation can be due to an anal fissure, anal carcinoma or strangulated haemorrhoids.
Haemorrhoids per se are not painful. Anal fissures are common in young adults and have an increased
incidence following pregnancy.
Scenario 2
A 32-year-old man presents with a 1-week history of colicky lower abdominal pain. This is associated with bloody
diarrhoea, increased stool frequency and weight loss. A mass is palpable in the right iliac fossa. He is anaemic
and has a CRP of 200.
B - Anal fissure « YOUR ANSWER
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Dr Mohammed Shamsul Islam Khan, Medical Officer, Clinical Neuro-Surgery, National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh. Mobile: +880 1713 455 662, +880 1685 811979. E-mail: drsikhan@gmail.com
Page |
1570
MyPasTest: MRCS A Online - Jan Exam 2015
26. Surgical Specialities; General Surgery; Colorectal Surgery (36Qs)
F - Crohn’s disease« CORRECT ANSWER
F – Crohn’s disease
This history is typical of inflammatory bowel disease. The most likely diagnosis here would be Crohn’s
disease in view of the weight loss and a palpable mass. These latter features are uncommon in ulcerative
colitis.
Scenario 3
A 37-year-old homosexual presents with a 3-month history of episodes of bright red rectal bleeding associated
with pain and itching. On examination he has an area of ulceration at the anal verge with an everted irregular
edge.
C - Angiodysplasia « YOUR ANSWER
A - Anal carcinoma « CORRECT ANSWER.
A – Anal carcinoma:
Anal carcinoma has a strong association with human papillomavirus (types 16, 18, 33) infection. The
everted edge is characteristic of a neoplastic process and a carcinoma should be suspected. Bleeding is
another common presentation of anal carcinoma.
Editor:
Dr Mohammed Shamsul Islam Khan
MBBS (CMC); FCPS-II (Neuro-Surgery)
Medical Officer, Clinical Neuro-Surgery
National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh.
Mobile: +880 1713 455 662, +880 1685 811979.
E-mail: drsikhan@gmail.com
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Dr Mohammed Shamsul Islam Khan, Medical Officer, Clinical Neuro-Surgery, National Institute of Neuro-Sciences and Hospital
Sher-E-Bangla Nagar, Dhaka-1207, Bangladesh. Mobile: +880 1713 455 662, +880 1685 811979. E-mail: drsikhan@gmail.com
Page |
1571