tbl 5 nigel fong approach to jaundice and lft

Question 1

1. Pre- Hepatic Jaundice
   Raised unconjugated bilirubin may be due to increased bilirubin production, or impaired hepatic uptake.

(a) Is there haemolysis? A classic example with G6PD deficiency which develops jaundice after inadvertently taking ______________, which causes haemolysis. Look for: Predisposition of known haemolytic disease:
- G6PD deficiency, thalassemia, chronic lymphoid leukaemia, recent exposure to drugs causing haemolysis, recent blood transfusion and so forth.
- Biochemical evidence of haemolysis: apart from raised unconjugated bilirubin, this includes raised __________________, low haptoglobin, raised reticulocyte count, peripheral blood film findings of haemolysis (e.g. schistocytes and bite cells) and a positive direct Coomb’s test.

(b) Look for causes of impaired hepatic uptake. If there is no evidence of haemolysis, consider other causes of impaired hepatic uptake of bilirubin.
- Medications: for example, ________ and probenecid
- Gilbert’s syndrome: This is a genetic defect of _____________, resulting in decreased hepatic conjugation of bilirubin, which can be more marked in times of stress. A presumptive diagnosis can be made in an asymptomatic patients with mildly elevated unconjugated bilirubin levels and otherwise normal LFTs, if haemolysis and medications causing raised bilirubin are excluded. It is a benign disorder with no untoward consequence. Additional evaluation is not routinely necessary.

Answer 1

trimethoprim-sulphamethoxazole (bactrim);

lactate dehydrogenase (LD);

rifampicin;

UDP- glucuronyl transferase

Question 2

2. Hepatic Jaundice/ Hepatocellular Pattern of raised LFT
   - Conjugated hyperbilirubinaemia with raised ALT and AST reflects hepatocellular injury. Note that the normal upper limit of ALT is __________ for males and __________ for females. Levels above this are associated with increased liver related mortality and should be investigated.

Clinical syndromes

• Hepatic injury may be acute or chronic, fulminant or subclinical. Consider this range of clinical syndromes.
• Minimally symptomatic: Many patients have minimal symptoms.
• Cirrhosis: Recurrent episodes of liver damage and regeneration results in gradual progression from chronic hepatitis to fibrosis and eventually cirrhosis. - Look for evidence of cirrhosis especially splenomegaly, ascites, thrombocytopenia and features of chronic hyperestrogenism. Abdominal imaging reveals liver nodularity. Severity of cirrhosis may be graded by the CHild- Pugh and Model of End stage Liver Disease (MELD) scoring systems.
• Acute symptomatic: Some patients present with an acute onset of jaundice or fulminant liver failure (encephalopathy, _________________). This can occur de novo, or from a new insult superimposed on chronic hepatitis/ cirrhosis.
• Massive transaminitis: while 4- or 5- digit AST and ALT levels inspire fear, ________________) provides a far better reflection of disease severity than AST/ ALT levels per se. Massive transaminitis tends to be seen in in ischaemic, viral amd toxic (especially paracetamol causes)
• Hepatic jaundice in pregnancy: a number of additional differentials apply.

Answer 2

29 to 33 IU/L; 10 to 25 IU/ L;

coagulopathy, hypoglycaemia;

liver dysfunction (coagulopathy, hypoglycaemia etc

Question 3

Additional considerations in pregnancy

• Intrahepatic cholestasis of pregnancy: Presents in 2nd to 3rd trimester with __________________, but women are otherwise well.
• Acute fatty liver of pregnancy: Presents in third trimester with liver dysfunction (jaundice, elevated AST/ ALT, coagulopathy), abdominal pain, nausea/ vomiting and often ___________
• HELLP syndrome: presents in third trimester with ________________________. This is thought to be a severe form of pre-eclampsia, often with hypertension, proteinuria, abdominal pain and vomiting.

Answer 3

pruritus and raised bilirubin;

renal impairment;

haemolysis, Elevated LFTs and Low Platelets;

Question 4

(a) Painful obstructive jaundice
- Aetiology: Painful obstructive jaundice is almost always due to gallstone disease.
- Cholangitis: infections of an obstructed biliary system presents with ____________________ (charcot’s triad). Obstruction is usually due to gallstones
- ______________: Gallstones obstructing the common bile duct, without evidence of infection
- Hepatic abscess: May also present with right hypochondrial pain and jaundice.

Hepatobiliary imaging (ultrasound/ CT) distinguishes between these aetiologies. Note that marked jaundice is inconsistent with biliary colic or simple cholecystitis. If present, cholangitis must be considered.

Approach to suspected cholangitis

• Early treatment of sepsis: cholangitic patients deteriorate rapidly, so empiric treatment must be instituted without awaiting imaging confirmation. Obtain blood cultures (these are frequently positive) and begin antibiotics urgently
• Hepatobiliary imaging: The next step is to do ultrasound/ CT scan. In this setting, a ______________ confirms the clinical diagnosis of cholangitis; gallstones may be visible in the common bile duct as hyper-echoic lesions casting an acoustic shadow, or may be obscured (especially on ultrasound as gastric air obscures the distal common bile duct). Imaging may also identify a ring enhancing hepatic lesion, diagnostic of hepatic abscess.
• Biliary drainage: after confirmation of dilated ducts, pursue endoscopic retrograde cholangiopancreatography (ERCP) or _________________. While useful to confirm biliary dilation and intra-ductal stones, these are invasive and not performed solely for diagnosis. Their main utility is therapeutic- achieving source of infection. ECRP allows stenting or sphincterotomy with stone extraction, while in PTBD, an external drain is inserted into the biliary tree (favourable in unstable patients in whom sedation is risky).

Answer 4

right hypochondrial pain, jaundice and fever;

Choledocholithiasis;

dilated common bile duct;

percutaneous transhepatic biliary drainage (PTBD)

Question 5

(b) Painless Obstructive Jaundice

Extrahepatic biliary obstruction

• Periampullary mass: Painless progressive jaundice is the classic presentation of a periampullary cancer, for example, of the head of pancreas, ampulla of vater, a distal cholangiocarcinoma or malignant periampullary lymph nodes (as in lymphoma). These patients often have constitutional symptoms and weight loss.
• Strictures: in __________________ (an autoimmune disease associated with IBD), strictures complicating prior biliary intervention or cholangiocarcinoma presenting as a stricture.
• Other causes: Liver flukes, AIDS cholangiopathy (in advanced HIV with CD4<100)

Intrahepatic cholestasis

• Primary biliary cholangitis (PBC): An autoimmune disease classically presenting in middle-aged females with cholestatic jaundice, pruritus, ___________ and hepatosplenomegaly. Anti-mitochondrial antibodies are sensitive (positive in almost all cases of PBC) and specific (rarely positive in other diseases).
• Drugs: a number of drugs cause intrahepatic cholestasis including antibiotics (____________, rifampicin, erythromycin), _____________, immunosuppressants (azathioprine and ___________), the oral contraceptive pill and others.

Other causes: diffuse liver infiltration with metastatic cancer, hepatic abscess and so forth

Answer 5

primary sclerosing cholangitis;

xanthelasma;

beta-lactams; antithyroid drugs; cyclosporine