Past exam of the medicine course of the University of Oxford / 1864 / Second examination / Pathology. medical, surgical / 6 / Solution

Jaundice results from accumulation of bilirubin; its reversibility depends on the cause, not on the yellow colour alone. In 1864, obstruction of bile flow and disease of the liver were important practical distinctions. Modern physiology also separates excess production from impaired uptake, conjugation and excretion.

Excess breakdown of red blood cells can overwhelm the usual handling of bilirubin, producing predominantly unconjugated hyperbilirubinaemia. Impaired hepatic uptake or conjugation supplies another non-obstructive mechanism. Hepatocellular injury, as in hepatitis or advanced cirrhosis, impairs processing and secretion. Intrahepatic cholestasis and extrahepatic obstruction prevent normal disposal through bile. Obstruction can result from a gallstone, a duct stricture, inflammation or compression/invasion by a tumour.^[ref]

Conjugated bilirubin can enter the urine, making it dark; predominantly unconjugated bilirubin, which is strongly protein-bound, does not ordinarily produce bilirubinuria. Marked interruption of bile delivery can make stools pale. These findings help locate the problem but do not by themselves distinguish a stone from a stricture or cancer. Modern fractionated bilirubin tests, liver enzymes and ultrasonography supplement the clinical pattern.^[ref]

Recovery “by nature” is possible when an obstruction is temporary, a small gallstone passes, a reversible inflammatory process settles, or the cause of increased pigment production ceases. An episode of jaundice can clear as liver function recovers. It is nevertheless unsafe to infer a harmless or self-limiting cause merely because the jaundice fluctuates; partial malignant obstruction can also fluctuate.

Recovery “by art,” in modern terms, includes treating a reversible underlying illness and relieving a remediable obstruction. A persistent common-duct stone can be removed endoscopically or surgically; an obstructed duct may require drainage. Selected strictures and tumours can be treated, but established extensive hepatic destruction or disseminated malignancy may prevent full recovery even if bile drainage is improved.^[ref] These are present capabilities, not a claim that modern endoscopy was available to the 1864 examiner.

The period question therefore calls for a conditional prognosis: a movable obstruction or reversible disturbance offers a better prospect than irreversible tissue destruction or an untreatable growing obstruction. A disappearing colour is not, by itself, proof that the underlying disease has been cured.