Workshop on jaundice..

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Workshop on jaundice
Paul Lai
Put down in your sheet a flow chart
explaining the bilirubin metabolism
Keywords:
bilirubin, conjugation, urobilinogen, stercobilinogen,
spleen, liver, terminal ileum, colon, kidney
Put down in your sheet a flow chart
explaining the bilirubin metabolism
Urobilinogen
absorbed into
blood stream
(get to the
kidney and
excreted in
urine
Unconjugated
bilirubin from
RBC
destruction
Conjugated
bilirubin (in
hepatocytes)
Excretion into
duodenum
thro’ bile
ducts
Converted to
Urobilinogen
(in terminal
ileum)
Converted to
Stercobilinogen
(excreted in
faeces)
Urobilinogen
absorbed into
portal system
and go back
to liver
Comparison between conjugated
and unconjugated bilirubin
• Unconjugated bilirubin
• Conjugated bilirubin
Comparison between conjugated
and unconjugated bilirubin
• Unconjugated bilirubin
– Insoluble in blood
– Largely attached to albumin in
blood
– Accumulates in pre-hepatic
jaundice
– Is toxic to tissues and organs
such as the brain
– Cannot be excreted in the
urine
• Conjugated bilirubin
– Is water soluble
– Small amounts are loosely
bound to albumin in blood
– Accumulates in posthepatic jaundice
– Relatively non-toxic
– Can be excreted in the
urine
What is the surgical significance of
enterohepatic circulation of bile salts?
What is the surgical significance of
enterohepatic circulation of bile salts?
• Primary bile salts help solubility of lipids allowing
their absorption in the jejunum
• After resection of terminal ileum (as in cases of
right hemicolectomy for cancer), patient may
have diarrhoea
• Failure of resorption of bile acids may also lead
to steatorrhoea
Put down in your sheets the differential diagnosis
of pre-hepatic, hepatic and post-hepatic jaundice
•
Pre-hepatic
•
Hepatic
•
Post-hepatic
Put down in your sheets the differential diagnosis
of pre-hepatic, hepatic and post-hepatic jaundice
•
Pre-hepatic
– Haemolytic
anaemia
– Incompatible
blood
transfusion
– Resorption of
haematoma
– spherocytosis
•
Hepatic
– Cirrhosis of
liver
– Hepatitis
– Drug and toxin
reactions
– Pre-maturity
– Crigler-Najjer
syndrome
– Gilbert
syndrome
– DubinJohnson
syndrome
– Severe sepsis
– SOL in the
liver (mass
effects by
tumours or
abscess)
•
Post-hepatic
– Obstruction of extrahepatic bile duct due to
gallstones / CBD stones/
Mirrizi syndrome
– Strictures (primary
sclerosing cholangitis,
primary biliary cirrhosis,
iatrogenic strictures)
– Tumours
(cholangiocarcinoma,
ampullary cancer,
pancreatic head cancer
– Cholestasis (canaliculi
obstruction) due to
hepatitis, pregnancy, TPN,
drug reactions
It is wrong to simply classify jaundiced patients in having “medical jaundice” or “surgical jaundice”
How to differentiate pre-hepatic, hepatic and posthepatic jaundice ?
•
Pre-hepatic
•
Hepatic
in terms of
1.
2.
3.
4.
5.
Color of urine
Color of stool
ALP level
ALT level
PT
•
Post-hepatic
How to differentiate pre-hepatic, hepatic and posthepatic jaundice ?
•
Pre-hepatic
– Urine of normal
color
– Stool of normal
color
– ALP normal
– ALT normal
– PT normal
•
Hepatic
– Urine of dark
color
– Stool of
normal color
– ALP mildly
raised (except
in PBC)
– ALT can be
high if hepatitis
or cirrhosis
present
– PT prolonged
(and not
correctable by
vit. K)
•
Post-hepatic
– Urine of dark
color (but no
urobilinogen)
– Stool of pale
color
– ALP usually
very high
– ALT may be
slightly raised
– PT prolonged
but correctable
by vit. K
Important details in the history in patients
presenting with jaundice
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Duration of jaundice
Previous attack of jaundice
Any pain
Any fever, chills and rigor
Itchiness of skin (pruritus)
Fat intolerance
Exposure of drugs (including TCM)
Systemic symptoms like weight loss, anorexia, general malaise
Color of the sclera, urine and stool
Contact with other jaundice patients
History of hepatitis, IVDA, blood transfusions (especially transfusions long
time ago)
Occupations
Alcohol consumption
Family history of blood disorders, hepatitis or liver cancer
Important details in the physical examination
in patients presenting with jaundice
•
General examination
– Depth of jaundice (Sclera, skin, mucus membrane)
– Scratch marks
– Stigmata of chronic liver diseases
•
•
•
•
•
•
Abdominal examination
–
–
–
–
–
–
•
Palmar erythema
Clubbing of fingers
White nails
Duputytren’s contracture
Gynaecomastia
Liver (size, shape, surface)
If the gallbladder is palpable
Splenomegaly
Prominent abdominal wall veins
Ascites
Other abdominal masses
Rarities
– Kayser-Fleischer rings [Wilson’s disease]
– Xanthmata [primary biliary cirrhosis]
LFTs and USG
• LFTs
– Raised bilirubin in confirming the presence of jaundice
– Raised enzymes (ALP / ALT)
– Albumin (a low albumin level in a jaundice patient suggests chronic liver
disease)
– PT/APTT/INR (important to correlate clotting profile and liver functions)
• *contribute to Child’s grading (bilirubin, albumin, PT)
• USG
– Almost always the first line of investigation
– To look for dilated intrahepatic and extrahepatic bile ducts
– Other things to pick up:
•
•
•
•
Presence of gallstones and thickening of GB
Presence of SOL or tumours (in the liver, porta hepatis, GB or pancreas)
Presence of ascites
Presence of splenomegaly and varices
Cholangiograms
• By endoscopic route: ERCP
• By percutaneous route: PTBD
• By MR imaging: MRCP
•
•
By operative route: intra-operative cholangiogram
Intravenous cholangiograms are almost obsolete these days
• Always need to drain the biliary system (to relief
obstruction) urgently if there are signs of acute
cholangitis and septicaemia (septic shock)
• Also needs to consider the invasiveness, availability of
expertise & resources as well as the cost involved
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