Jaundice
Types of jaundice and their clinical features
'other' | haemolytic | hepatocellular | cholestatic | |
---|---|---|---|---|
location | varies | pre-hepatic | hepatic | post-hepatic |
urine | normal | normal | dark | dark |
stools | normal | normal | normal / pale | pale |
total bilirubin | + | + | +/++ | +++ |
important history | jaundice with fasting or stress such as infection (Gilbert's) | travel, family history | drug and alcohol history | history of pain (suggests cholelithiasis) |
important signs | splenomegaly may be present | signs of chronic liver disease | absent splenomegaly | |
ALP | normal | normal | raised (along with ALT, AST or GGT) | raised (more than ALT, AST or GGT) |
important causes | neonatal jaundice, Gilbert syndrome, Crigler-Najjar syndrome | malaria, sickle cell anaemia, G6PD, thalassemia, alpha methyldopa | alcoholic liver disease, hepatotoxicity from drugs | gallstone (cholelithiasis), cancer of the head of pancreas |
Differentiating causes of jaundice is based on clinical and laboratory features.
Total obstruction of the bile duct will lead to no urobilinogen in the urine since urobilinogen is made (and some is reabsorbed the 'enterohepatic urobilinogen cycle') in the gut.
Laboratory features of haemolytic anaemia include macrocytosis / reticulocytosis, raised 'unconjugated bilirubin', raised LDH, immature (left-shift) red cells (polychromasia).
Jaundice due to very heavy malaria infection can be associated with 'blackwater fever' although this is quite rare. The discolouration of the urine is due to haemoglobin.