Hepatitis

Hepatitis means inflammation or injury of the liver. The word identifies the organ process, not its cause. Viral infection, alcohol, medications or supplements, autoimmune disease, metabolic dysfunction-associated steatotic liver disease, biliary disease, ischaemia, and inherited disorders can all produce hepatitis. The first clinical question is whether the injury is acute, chronic, or already progressing to liver failure. Acute hepatitis may cause fatigue, anorexia, nausea, fever, arthralgia, right upper quadrant discomfort, pruritus, jaundice, or dark urine, but some patients have no symptoms. Chronic viral hepatitis is often silent until fibrosis, cirrhosis, or hepatocellular carcinoma develops. A normal appearance therefore does not exclude clinically important disease. The biochemical pattern narrows the differential: - Hepatocellular injury: ALT and AST rise disproportionately. Viral hepatitis, acetaminophen toxicity, autoimmune hepatitis, ischaemic injury, Wilson disease, and some medications are possibilities. - Cholestatic injury: alkaline phosphatase and GGT predominate. Biliary obstruction, primary biliary cholangitis, primary sclerosing cholangitis, and cholestatic drug injury move higher on the list. - Mixed injury: both aminotransferases and cholestatic enzymes are substantially elevated. HBV provides an important example of mechanism. The virus itself is...