Jaundice

• Visible when plasma bilirubin is raised >35?g/L
• Bilirubin is formed from the breakdown of Hb
• It is conjugated to glucuronic acid in the liver (making it water soluble) and released into the bile, passing into the gut
• Some of this is taken up again by the liver via the eterohepatic circulation
• The rest is converted by bacteria into urobilinogen by gut bacteria
• This is either reabsorbed and excreted by the kidney or converted to stercobilin which make the faeces turn brown

Pre-hepatic jaundice

• Occurs if there is increased production, reduced hepatic uptake or reduced conjugation
• Causes;
  • Physiological (neonatal)
  • Haemolysis
  • Dyserthropoiesis
  • Glucuronyl transferase deficiency (Gilbert’s and Crigler-Najjar syndrome)

Hepatocellular jaundice

• There is hepatocyte damage usually with some cholestasis
• Causes
  • Viral hepatitis
  • Liver metastases/abscess
  • Haemochromatosis
  • Autoimmune hepatitis
  • Septicaemia
  • ?1- antitrypsin deficiency
  • Budd-Chiari syndrome (hepatic vein obstruction)
  • Wilson’s disease
  • Failure to secrete conjugated bilirubin – Dubin-Johnson and Rotor syndrome

Cholestatic jaundice

• Occurs when the bile duct(s) get blocked
• Results in pale stools and dark urine
• Associated with puritis
• Causes;
• CBD stones
• Pancreatic carcinoma
• Lymph nodes at the porta hepatis
• Drugs
• Cholangiocarcinoma
• Primary sclerosis cholangitis
• Bilary atresia
• Mirrizi’s syndrome – obstructive jaundice secondary to compression of the common hepatic duct by a gallstone impacted in the cystic duct. Associated with cholangitis

A palpable gallbladder in conjunction with a painless jaundice suggests a cause other than gallstones – Courvoisier’s law

Tests for Jaundice

• Haematology – FBC, clotting, blood film, reticulocyte count, Coomb’s test
• Biochemistry – U&Es, LFTs (bilirubin, AST, ALT, alk phos, ?-GT, total protein, albumin. Albumin and INR are the best indicates of liver synthetic function
• Ultrasound – are the bile ducts dilated (>6mm)? are there gallstones, hepatic masses or pancreatic masses?
• ERCP
• MRCP
• Liver biopsy

Drug induced jaundice

• Haemolytic
  • Antimalarials
• Hepatitis
  • Paracetamol
  • Anti-TB drugs – rifampacin, isoniazid, pyrazinamide
  • Statins
  • Sodium valproate
  • Halothane
• Cholestasis
  • Antiobiotics – flucloxacillin, fusidic acidm co-amoxiclav, nitrofurantoin
  • Anabolic steroids
  • OCP

Causes of jaundice in a previously stable patient with cirrhosis

• Sepsis
• Alcohol
• Drugs
• Malignancy (hepatocellular carcinoma)
• GI bleeding