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Causes of Hepatitis

By

Sonal Kumar

, MD, MPH, Weill Cornell Medical College

Last full review/revision Dec 2020| Content last modified Dec 2020

Hepatitis is an inflammation of the liver characterized by diffuse or patchy necrosis.

Hepatitis may be acute or chronic (usually defined as lasting > 6 months). Most cases of acute viral hepatitis resolve spontaneously, but some progress to chronic hepatitis.

Common Causes of Hepatitis

Common causes of hepatitis include

At least 5 specific viruses appear to be responsible for hepatitis (see table Characteristics of Hepatitis Viruses). Other unidentified viruses probably also cause acute viral hepatitis.

Less Common Causes of Hepatitis

Less common causes of hepatitis include autoimmune disorders, genetic liver disorders, and other viral infections (eg, infectious mononucleosis, yellow fever, cytomegalovirus infection) and leptospirosis.

Parasitic infections (eg, schistosomiasis, malaria, amebiasis), pyogenic infections, and abscesses that affect the liver are not considered hepatitis. Liver involvement with tuberculosis (TB) and other granulomatous infiltrations is sometimes called granulomatous hepatitis, but the clinical, biochemical, and histologic features differ from those of the diffuse liver involvement in hepatitis caused by hepatitis viruses, alcohol, and drugs.

Various systemic infections and other illnesses may produce small focal areas of hepatic inflammation or necrosis. This nonspecific reactive hepatitis can cause minor liver function abnormalities but is usually asymptomatic.

Some types of infectious and noninfectious liver inflammation are summarized in table Selected Infections With Liver Involvement.

Selected Infections With Liver Involvement

Disease or Organism

Manifestations

Viruses

Cytomegalovirus

In neonates: Hepatomegaly, jaundice, congenital defects

In adults: Mononucleosis-like illness with hepatitis; may occur posttransfusion

Epstein-Barr virus infections

Infectious mononucleosis

Clinical hepatitis with jaundice in 5–10%; subclinical liver involvement in 90–95%

Acute hepatitis sometimes severe in young adults

Herpes simplex virus

Anicteric hepatitis, usually in immunocompromised patients (but can also occur in immunocompetent patients)

Fever in the majority; rash in 50%

Acute hepatitis, often severe

Yellow fever

Jaundice, systemic toxicity, bleeding

Liver necrosis with little inflammatory reaction

Other

Hepatic infection occasionally due to echovirus or coxsackievirus infections, varicella, herpes simplex, rubella, or rubeola

Bacteria

Actinomycosis

Granulomatous reaction of liver with progressive necrotizing abscesses

Pyogenic abscess*

Serious infection acquired via portal pyemia, cholangitis, or hematogenous or direct spread; due to various organisms, especially gram-negative and anaerobic

Illness and toxicity, yet only mild liver dysfunction

Tuberculosis

Hepatic involvement (common; usually subclinical) with granulomatous infiltration; jaundice (rare)

Disproportionately increased alkaline phosphatase

Other

Minor focal hepatitis in numerous systemic infections (common; usually subclinical)

Fungi

Histoplasmosis

Granulomas in liver and spleen (usually subclinical) that heal with calcification

Other

Granulomatous infiltration sometimes occurring in cryptococcosis, coccidioidomycosis, blastomycosis, or other infections

Protozoa

Amebiasis*

Important disease, often without obvious dysentery

Usually a large single abscess with liquefaction

Systemic illness, tender hepatomegaly, surprisingly mild liver dysfunction

Malaria

A common cause of hepatosplenomegaly in endemic areas

Jaundice absent or mild unless active hemolysis is present

Toxoplasmosis

Transplacental infection

In neonates: Jaundice, central nervous system (CNS) and other systemic manifestations

Visceral leishmaniasis

Infiltration of reticuloendothelial system by parasite, hepatosplenomegaly

Helminths

Ascariasis

Biliary obstruction by adult worms, parenchymal granulomas caused by larvae

Clonorchiasis

Biliary tract infestation, cholangitis, stones, cholangiocarcinoma

Echinococcosis

One or more hydatid cysts, which usually have a calcified rim and may be large but which often are asymptomatic and do not disrupt liver function

Can rupture into the peritoneum or biliary tract

Fascioliasis

Acute: Tender hepatomegaly, fever, eosinophilia

Chronic: Biliary fibrosis, cholangitis

Schistosomiasis

Periportal granulomatous reaction to ova with progressive hepatosplenomegaly, pipestem fibrosis, portal hypertension, and varices

Hepatocellular function preserved; not true cirrhosis

Toxocariasis

Visceral larva migrans syndrome

Hepatomegaly with granulomas, eosinophilia

Spirochetes

Leptospirosis

Acute fever, prostration, jaundice, bleeding, renal injury

Liver necrosis (often mild despite severe jaundice)

Syphilis

Congenital: Neonatal hepatosplenomegaly, fibrosis

Acquired: Variable hepatitis in secondary stage, gummas with irregular scarring in tertiary stage

Relapsing fever

Borrelia infection

Systemic symptoms, hepatomegaly, sometimes jaundice

*Differentiate from amebiasis with serologic tests for amebas and direct percutaneous abscess aspiration.

Drugs Mentioned In This Article

Drug Name Select Trade
isoniazid LANIAZID

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