Acute viral hepatitis can be caused by any one of the Hepatitis A, Hepatitis B, Hepatitis C, Hepatitis E and  Delta viru,Epstein-Barr virus, cytomegalovirus, herpes simplex virus, rubella virus and virus of yellow fever.

Hepatitis A Virus

This is a RNA virus transmitted by fecoral route. Incubation period is 2-6 weeks. It leads to acute hepatitis and  does not lead to chronic disease or carrier state. Jaundice does not occur in half of the patients.

Hepatitis B Virus

This is a DNA virus transmitted parenterally or sexual intercourse. Workers dealing with blood products are at a higher risk.. The incubation period is 2-25 weeks. About 10 percent patients develop chronic disease or a carrier state.

Hepatitis C Virus

This is a single standard RNA virus transmitted parenterally. The incubation period varies from 2-25 weeks. About 20-30 percent develop chronic hepatitis, 50 percent of which is chronic active hepatitis which would ultimately lead to cirrhosis of liver.

Hepatitis E

This is caused by RNA virus. It resembles Hepatitis A, it is transmitted by feco-oral route and is found to occur in endemic areas like India, Asia, Africa and Central America. It is seen to occur in individuals who are immune to Hepatitis A Virus infection.

Delta Virus

This is a small RNA virus which is infectious only in presence of Hepatitis B surface antigen. It is thus a “superinfection” to hepatitis B infection with a rise in liver function tests. It usually has a chronic severe clinical course.

Other viruses:

Epstein-Barr virus, cytomegalovirus, herpes simplex virus, rubella virus and virus of yellow fever may all cause hepatitis.

Pathology

• Mononuclear cell infiltration
• Cellular ballooning and necrosis
• Condensed cytoplasm with pyknotic nuclei also called acidophilic bodies.

Clinical Features

• Influenza-like syndrome is common in hepatitis a with malaise, anorexia and fatigue
• Arthritis and urticaria is common with hepatitis B and is probably due to circulating immune complexes
• Jaundice with dark urine and light stool occur in 50 percent of patients
• Tender hepatomegaly is common and splenomegaly occurs in 20 percent of cases

Investigations

• Elevated SGOT, SGPT, LDH, Bilirubin and alkaline phosphatase
• Specific viral marker tests

Complication of Acute Viral Hepatitis

1. Fulminant hepatic failure
2. Relapsing hepatitis
3. Cholestatic hepatitis
4. Post-hepatitis syndrome
5. Chronic hepatitis
6. Cirrhosis of liver
7. Hepatocellular carcinoma
8. Aplastic anemia
9. Henoch Schonlein purura
10. Renal failure
11. Connective tissue disease
12. Papular acrodermatitis

Treatment

• Rest
• High calorie diet
• Avoid fatty foods
• No  hepatotoxic drug or alcohol to be taken
• Continuous monitoring by clinical and labortary parameters