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
- 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