Inflammation of liver damage to liver cells cell death. Most common causes are viral, alcohol and drugs.
Acute Viral Hepatitis:
Clinical syndrome of variable severity caused by hepatotropic virus. Often asymptomatic – 40% of adults can have antibodies to hepatitis ( subclinical infection)
5 types: HAV, HBV, HCV, HDV, HEV (up to 2% of cases due to other viruses, eg cytomegalovirus, Epstein-Barr virus).
Hepatitis A (HAV):
RNA virus; Short incubation (15-30 days) - spread primarily by faecal-oral contact, often in institutions; highly infectious; children more commonly affected; overcrowding and poor sanitation increase risks;
Short duration mild fever with vomiting, loss of appetite, jaundice, joint pain, tender hepatomegaly and adenopathy – recovery in a few days good prognosis
Treatment – reassurance; avoid alcohol
Prevention – after initial infection immunity
Hepatitis B (HBV):
Double shelled DNA virus; Incubation 40-180 days – follows blood transfusion or sexual contact; higher risk in homosexuals, those with haemophilia, IV drug users, institutionalised (eg prison) and health care workers
• preicteric – weakness, nausea, vomiting, enlargement and tenderness of liver; may be skin rash; darkening of urine; jaundice (<30% after 2 months) • icteric • convalescent Treatment – supportive; avoidance of alcohol; immunisation of sexual partner(s) Complications – liver failure; chronic hepatitis; glomerulonephritisHepatitis C (HCV): From blood transfusion or contact with infected blood Clinically similar to HBV, but generally less severe 50% chronic hepatitis; 5% cirrhosisHepatitis D (HDV): Needs HBV for replication as it is in incomplete RNA virus (delta agent) has same sources of spread as HBV Increases incidence of acute liver failure and cirrhosis in those with HBV infectionHepatitis E (HEV): Non-enveloped single strand RNA virus; Similar to HAV. Transmitted by the faecal-oral route – causes water borne epidemics during rainy seasons in parts of Africa, Asia and South AmericaGeneral clinical features: Usually get prodromal features (headache, malaise, chills) from 2-3 days up to two weeks prior to onset of jaundice; gastrointestinal symptoms; nausea; vomiting; diarrhoea; upper abdominal painDifferential diagnosis – drugs, alcohol, infectious mononucleosis, malaria, leptospirosisManagement: No specific treatment; adequate diet; interferon is helpful in some typesChronic Hepatitis: Hepatitis >6 months considered chronic.
HBV & HCV main causes