ABIM_GI_Hepatology

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ABIM
Gastroenterology and
Hepatology Review
Medicine Intern
A 66-year-old woman has a 2-month history of
intermittent burning epigastric pain that is worse at night
and during fasting. She has mild nausea but no vomiting,
melena, or hematochezia. The patient has lost 1.3 kg (3
lb) during this time. Over-the-counter antacids have not
relieved the pain. She has mild hypertension and
incapacitating degenerative joint disease. Medications
include a daily thiazide diuretic and ibuprofen three times
daily.
Physical examination reveals epigastric tenderness to
palpation and degenerative joint changes in the hands.
Upper endoscopy demonstrates several superficial antral
erosions and a 7-mm ulcer in the duodenal bulb. Antral
biopsy specimens show chemical-induced gastropathy
and no evidence of Helicobacter pylori. The patient
refuses to stop taking ibuprofen because of the
incapacitating pain in her hands.
which of the following is the most
appropriate next step in managing this
patient?
A An H2-receptor antagonist
B A liquid antacid
C A proton pump inhibitor
D A prostaglandin-E1 analogue
E Sucralfate
Correct answer is C
Proton pump inhibitors are the agents of choice when
treating a patient with an active NSAID-induced ulcer
when the patient cannot discontinue the NSAID. The
effectiveness of proton pump inhibitors in this situation is
most likely secondary to the potent acid inhibitory effect
of these agents.
Liquid antacids have not helped this patient previously,
and there is no reason to recommend their use again.
Several comparative trials have demonstrated the
ineffectiveness of H2-receptor antagonists and sucralfate
when NSAIDs are continued. Prostaglandin analogues
are effective for preventing NSAID-induced lesions but
are less effective for the treatment of active ulcers.
Transitional Intern
A 68-year-old man has a 4-month history
of difficulty swallowing both solids and
liquids. He describes “food sticking high
up” (pointing to the suprasternal notch)
and occasionally notes coughing after a
meal with nasal regurgitation of
undigested food. His voice has changed
somewhat, and he has lost 13.5 kg (30 lb)
during this time. Medical history is
unremarkable, and physical examination is
normal.
Which of the following diagnostic
studies should be done next?
A Barium swallow
B Videofluoroscopy swallow
C Upper endoscopy
D Esophageal motility study
Correct answer is B
The patient is describing oropharyngeal
dysphagia, which is caused by a neurologic
defect or a defect of striated muscles that control
the initiation of swallowing. Patients typically
present with difficulty swallowing both solid
foods and liquids, often have episodes of
coughing and choking during meals, and
frequently have a change in voice quality. A
videofluoroscopy swallow is the most
appropriate initial study, as it is very sensitive for
detecting oropharyngeal disorders and
demonstrating whether the patient can protect
the airway.
Standard barium esophagography (barium
swallow) does not visualize the oropharynx, and
upper endoscopy does not evaluate
oropharyngeal function. Although an esophageal
motility study occasionally detects
oropharyngeal changes, it primarily evaluates
function of esophageal smooth muscle rather
than striated muscle and is therefore not a firstline test for diagnosing oropharyngeal
dysphagia.
R-2
A 40-year-old woman has an 18-year
history of ulcerative colitis that is limited to
the left side and has responded well to
mesalamine and occasional corticosteroid
enemas. Recent surveillance colonoscopy
with biopsies showed low-grade dysplasia.
Which of the following is the most
appropriate next step in managing
this patient?
A Repeat colonoscopy in 3 months
B Repeat colonoscopy in 1 to 2 years
C Administer sulindac
D Administer a low-dose corticosteroid
E Refer for colectomy
Correct answer is E
The finding of low-grade dysplasia on
surveillance colonoscopy is associated with
concurrent adenocarcinoma or progression to
high-grade dysplasia and cancer in up to 24% of
patients with chronic ulcerative colitis. Current
guidelines recommend colectomy for patients
with chronic ulcerative colitis and dysplasia of
any grade. Neither increased colonoscopic
surveillance nor more aggressive medical
therapy (such as administration of sulindac or a
low-dose corticosteroid) has been found to
reduce the risk of cancer in these patients.
Intern
A 48-year-old man is hospitalized because of
acute severe upper abdominal pain associated
with nausea and vomiting. The patient has mild
hypertension and poorly controlled type 2
diabetes mellitus (his most recent hemoglobin
A1C measurement was 10%). Medications are
glyburide, hydrochlorothiazide, an angiotensinconverting enzyme inhibitor, a statin, and lowdose aspirin, all of which he has been taking for
3 years. He does not drink alcoholic beverages
and has no recent history of abdominal trauma.
There is no family history of pancreatic disease.
Physical examination discloses only mild
epigastric tenderness to palpation without
rebound.
Laboratory Studies
Glucose 320 mg/dL
calcium 9.1 mg/dL
Phosphorus 3.9 mg/dL
total bilirubin0.1 mg/dL
aspartate aminotransferase 48 U/L
alanine aminotransferase 61 U/L
alkaline phosphatase 128 U/L
amylase 125 U/L
lipase390 U/L
Abdominal ultrasonography shows a
normal gallbladder without stones, mild
fatty liver disease, and normal bile duct
diameter. The pancreas is not well
visualized. A CT scan of the abdomen
shows marked peripancreatic stranding
with a small amount of fluid around the tail
of the pancreas.
Which of the following diagnostic
studies should be done next?
A Thyroid function tests
B Serum triglyceride measurement
C Repeat transabdominal ultrasonography
D Endoscopic ultrasonography
Correct answer is B
This patient presents with acute
pancreatitis of undetermined cause. He
may have hypertriglyceridemia because of
his poorly controlled diabetes mellitus. In
addition, the normal serum amylase value
may be a clue to the presence of an
elevated serum triglyceride level because
hypertriglyceridemia affects the accuracy
of the amylase assay and may cause
false-negative results. However, this
patient's serum triglyceride level was not
assessed initially and should be done now.
Hyper- or hypothyroidism is not a cause of acute
pancreatitis, and thyroid function tests are therefore
not indicated. The initial abdominal ultrasound
examination showed no gallstones or sludge.
Assuming that the original study was of good
quality, a repeat examination is not indicated at this
time. Although endoscopic ultrasonography is more
sensitive than transabdominal ultrasonography for
detecting gallbladder stones and sludge,
hyperlipidemia should be excluded before more
invasive studies are done.
R-3
A 66-year-old woman comes for her
annual physical examination. She reports
only mild fatigue. The patient has
prediabetes that is managed by diet alone.
She takes no medications and drinks one
glass of wine each day.
On physical examination, blood pressure
is 132/86 mm Hg. BMI is 32. The
remainder of the examination is normal.
Hemoglobin 13.1 g/dL
Platelet count 85,000/μL
Plasma glucose (fasting)119
mg/dL
Serum lipid profile Normal
aspartate aminotransferase
138 U/L
alanine aminotransferase 124
U/L
alkaline phosphatase 50 U/L
total bilirubin 0.8 mg/dL
albumin 3.1 g/dL
Serologic studies for hepatitis
A, B, and C Negative
Serum transferrin saturation
Normal
Urinalysis Normal
Abdominal ultrasonography shows
evidence of mild fatty infiltration of
the liver.
In addition to weight loss, which of the
following is the most appropriate next step
for managing this patient's liver chemistry
abnormalities?
A Rosiglitazone; repeat liver tests in 6
months
B Alcohol counseling
C Liver biopsy
D Evaluation for liver transplantation
Correct answer is C
This patient likely has nonalcoholic fatty liver disease
(NAFLD). A liver biopsy is indicated to determine whether
nonalcoholic steatohepatitis (NASH) or fibrosis is also
present. This distinction is important, as a patient with
evidence of cirrhosis should be screened for
complications of end-stage liver disease, such as
esophageal varices and hepatocellular carcinoma.
Although a liver biopsy is not required for all patients with
NAFLD, biopsy should be considered for those who are
older than 45 years of age, are obese, have diabetes
mellitus, or have a serum aspartate aminotransferase to
serum alanine aminotransferase ratio (AST:ALT) >1, as
these may be predictors of fibrosis. This patient has
several predictors for fibrosis, including her age, obesity,
and increased AST:ALT ratio. She also has a low serum
albumin level associated with a normal urinalysis, making
synthetic hepatic dysfunction of the liver likely. Her low
platelet count may also be a marker for hypersplenism
due to portal hypertension.
Rosiglitazone or pioglitazone could be considered for
patients with NASH and features of the metabolic
syndrome in order to prevent progression of the liver
disease, but NASH cannot be diagnosed without a
biopsy confirming necroinflammatory activity. The
patient's level of alcohol consumption is not enough to
warrant counseling; however, if evidence of fibrosis is
found, avoidance of all alcohol may be indicated.
Although liver transplantation may be required for 1% to
2% of patients with NASH, this patient's liver disease
appears to be well compensated, and evaluation for
transplantation is not indicated at this time.
Intern
A 67-year-old woman has a 3-month history of loose,
watery stools four to five times per day without bleeding,
weight loss, urgency, or fecal incontinence. The patient
has not traveled recently. She has a 45-year history of
type 1 diabetes mellitus, managed with insulin, and a 2year history of gastroesophageal reflux disease, treated
with a proton pump inhibitor. She recently received two
courses of antibiotics for recurrent cystitis, during which
time her diarrhea improved. She has been drinking milk
all her life without problems. Screening colonoscopy 1
year ago was normal.
Physical examination is notable only for peripheral
neuropathy and Charcot's joints. Stool examination for
ova and parasites and stool assay for Clostridium difficile
toxin are negative. Stool culture shows no growth of
pathog
Which of the following dietary changes
should be tried at this time?
A Begin a gluten-free diet
B Begin a lactose-free diet
C Add Lactobacillus acidophilus to the diet
D Increase dietary fiber
The correct answer is B
This patient likely has small bowel bacterial overgrowth.
Her history of longstanding diabetes mellitus with
associated neuropathy is a risk factor for development of
this disorder, which is most likely associated with inhibition
of gastric acid production. The fact that the diarrhea
improved during antibiotic therapy is another clue to this
diagnosis. Small bowel bacterial overgrowth frequently
recurs unless the contributing factors can be corrected.
However, the causative factor in this case is autonomic
diabetic neuropathy, which is unlikely to be improved.
Therefore, management of symptoms or, when severe,
management of malabsorption, should be tried first.
Patients with small bowel bacterial overgrowth often have
secondary lactose intolerance from a reduction in brushborder lactase that results from low-grade chronic
inflammation. Of the dietary trials listed, an empiric trial of a
lactose-free diet is the most reasonable first approach. If
this is unsuccessful, treatment with antibiotic monotherapy
or a regimen of different antibiotics on a rotating schedule
should be considered.
There is an association between diabetes mellitus and
celiac sprue, and patients with celiac sprue are at risk for
development of osteoporosis. However, an empiric trial
of a gluten-free diet is never justified in the absence of a
definitive diagnosis of celiac sprue, which includes small
bowel biopsies. There is no evidence that adding
Lactobacillus acidophilus to the diet is beneficial, and
administering a large bacterial load to a patient with
small bowel bacterial overgrowth may even exacerbate
the disorder. Increasing dietary fiber, although perhaps
not disadvantageous, is unlikely to be effective for
control of small bowel bacterial overgrowth.
R-2
A 48-year-old man with a long history of alcohol abuse is
brought to the emergency department for evaluation of
hematemesis. He has no other known medical problems,
takes no medications, and has never established regular
care with a physician.
On physical examination, the patient is obviously
intoxicated and barely arousable. Pulse rate is 115/min,
and blood pressure is 80/49 mm Hg. Spider angiomata
are present. Abdominal examination discloses a firm
liver edge and splenomegaly. Intravenous fluids are
begun, but before blood samples are drawn for
laboratory studies, the patient vomits a profuse amount
of bright red blood.
Which of the following is the most
appropriate management at this time?
A Intravenous β-blocker therapy
B Upper endoscopy
C Red blood cell transfusion
D Endotracheal intubation
E Transjugular intrahepatic portosystemic
shunt (TIPS)
The correct answer is D
This patient most likely has bleeding gastroesophageal varices
based on his history of alcohol abuse and physical examination
findings. Regardless of the cause of the bleeding, however, the
patient is intoxicated and barely arousable, and protection of his
airway with endotracheal intubation is paramount. All patients with
acute gastrointestinal bleeding associated with a decreased level of
consciousness, absent gag reflex, and continued hematemesis
require airway protection.
Although nonselective β-blocker therapy should be considered for
both primary therapy and secondary prevention of bleeding in
patients with cirrhosis and esophageal varices, initiating a β-blocker
is inappropriate in a patient with acute bleeding and hypotension.
Upper endoscopy is indicated once a patient is hemodynamically
stable in order to determine if the bleeding lesion can be treated with
endoscopic therapy. Although this patient may need a transfusion as
part of the resuscitation process, airway protection must be done
first. A transjugular intrahepatic portosystemic shunt (TIPS) may be
needed if the bleeding cannot be controlled with medical and
endoscopic therapy but is inappropriate as initial treatment.
R-3
A 45-year-old woman is undergoing
evaluation to determine the cause of iron
deficiency anemia. The patient is
otherwise healthy, and family history is
unremarkable. Colonoscopy shows a 2-cm
villous adenoma in the sigmoid colon; the
adenoma is removed during the procedure
In addition to counseling regarding
screening of family members, which of the
following is most appropriate at this time?
A Repeat colonoscopy in 6 months
B Repeat colonoscopy in 3 years
C Repeat colonoscopy in 10 years
D Annual fecal occult blood testing
E Referral for left hemicolectomy
Correct answer is B
This patient was found to have a high-risk lesion in the
sigmoid colon during colonoscopy that was done to help
diagnose the cause of iron deficiency anemia. High-risk
lesions include large polyps (>1 cm), polyps with villous
histologic features, and those with high-grade dysplasia.
Multisociety consortium guidelines recommend
surveillance colonoscopy 3 years from the time of initial
colonoscopy for patients with these findings and also
address issues regarding screening family members of
these patients.
Fecal occult blood testing is not a sensitive surveillance
study for the detection of polyps. Surgery, such as left
hemicolectomy, is not required because complete
removal of the polyp at the time of colonoscopy is
considered curative.
Intern
A 46-year-old woman is evaluated because of pain that
typically begins in her mid-chest and radiates to her left
arm. The pain can occur after meals, at rest, and during
exertion. The patient does not have dysphagia. Two
months ago, cardiac workup, including coronary
angiography, was negative, and upper endoscopy was
normal. Omeprazole, 20 mg twice daily for 2 months, did
not improve her symptoms.
When seen today, the patient appears anxious. Physical
examination is otherwise normal. Complete blood count
and chest radiograph are also normal.
Which of the following is the most
appropriate next step in managing this
patient?
A Begin a low-dose antidepressant
B Resume omeprazole; increase dose to
20 mg three times daily
C Add ranitidine at bedtime
D Schedule barium swallow
E Schedule esophageal motility study
The correct answer is A
This patient has noncardiac chest pain, which frequently
mimics symptoms of cardiac pain. A diagnosis of
noncardiac chest pain can only be made after a thorough
evaluation has ruled out a cardiac cause for the
symptoms. Noncardiac chest pain is believed to be
secondary to esophageal visceral hypersensitivity, and
patients are thought to have increased visceral pain
rather than increased sensitivity to somatic pain.
Low-dose antidepressants such as amitriptyline and
trazodone, which are thought to be effective modulators
of visceral sensation, may be helpful. Behavioral
modification, psychological counseling, and treatment of
any underlying anxiety issues may also be effective,
although it is difficult to determine the role that anxiety
plays in patients with noncardiac chest pain.
Increasing the dose of a proton pump inhibitor to more
than twice daily is not appropriate because gastric acid
secretion can be suppressed with twice-daily
administration in most patients. In addition, this patient
has not benefited from a previous trial of a proton pump
inhibitor. Ranitidine is a less potent antisecretory agent
than omeprazole and therefore is unlikely to be effective.
Barium swallow is helpful for evaluating dysphagia but is
not useful for diagnosing noncardiac chest pain and is
not recommended as the initial test for chest pain
because of its low specificity. Esophageal motility testing
also does not provide useful information in the evaluation
of noncardiac chest pain.
Intern
A 32-year-old obese woman with type 2
diabetes mellitus is scheduled to undergo
laparoscopic cholecystectomy for
treatment of symptomatic gallstones.
Abdominal ultrasonography shows
multiple gallstones without cholecystitis
and a normal common bile duct caliber.
Laboratory Studies
Plasma glucose180 mg/dL
aspartate aminotransferase 52 U/L
alanine aminotransferase 60 U/L
alkaline phosphatase 90 U/L
total bilirubin 0.6 mg/dL
Correct Answer is D
This patient, who is scheduled to undergo laparoscopic
cholecystectomy, has mildly elevated serum
aminotransferase values. Although abnormal
aminotransferase values typically occur in patients with
choledocholithiasis (common bile duct stones), this
patient has a normal common bile duct caliber. Her
serum alkaline phosphatase and bilirubin values are also
normal. The slightly abnormal laboratory values may
therefore be due to fatty liver alone. In this setting, no
additional preoperative tests are required, although the
surgeon may elect to perform intraoperative
cholangiography to identify any associated common bile
duct stones that can be removed either at the time of
surgery or postoperatively by endoscopic retrograde
cholangiopancreatography (ERCP).
ERCP is indicated preoperatively when a patient is likely
to have common bile duct stones that can be removed
by therapeutic ERCP. Preoperative ERCP is most
appropriate for patients with abnormal liver chemistry
values greater than twice the upper limit of normal
(including serum total bilirubin >3 mg/dL) associated with
common bile duct dilatation or jaundice. Biliary
scintigraphy (HIDA scan) that fails to visualize the
gallbladder will confirm a suspected diagnosis of chronic
cholecystitis but cannot diagnose common bile duct
stones. Given the ultrasonographic findings, a CT scan
of the abdomen is unlikely to provide any additional
information.
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