Hepatitis A

Key Features

Essentials of Diagnosis

• Gastrointestinal upset (anorexia, vomiting, diarrhea)

• Jaundice

• Liver tenderness and enlargement

• Abnormal liver function tests

• Local epidemic of hepatitis A infection

• Positive anti–hepatitis A virus (HAV) IgM antibody

General Considerations

• Epidemic outbreaks are caused by contaminated food or water supplies and by food handlers

• Sporadic cases usually result from contact with an infected individual

• Transmitted by the fecal-oral route

• Transmission through blood products obtained during the viremic phase is a rare event, although it has occurred in a newborn nursery

• Following an incubation period of 15–40 days, nonspecific symptoms usually precede jaundice by 5–10 days

• Risk factors

  • May include direct exposure to a previously jaundiced individual or recently arrived individual from a high prevalence country

  • Consumption of seafood

  • Contaminated water or imported fruits or vegetables

  • Attendance in a day care center

  • Recent travel to an area of endemic infection

Clinical Findings

Symptoms and Signs

• Two-thirds of children are asymptomatic

• Fever, anorexia, vomiting, headache, and abdominal pain are typical

• Dark urine precedes jaundice, which peaks in 1–2 weeks and then begins to subside

• Stools may become light- or clay-colored

• Tender hepatomegaly and jaundice are typically present

• Splenomegaly is variable

Differential Diagnosis

• Pancreatitis

• Infectious mononucleosis

• Leptospirosis

• Drug-induced hepatitis

• Wilson disease

• Autoimmune hepatitis and infection with other hepatitis viruses

• Acquired cytomegalovirus disease may also mimic HAV, although lymphadenopathy is usually present in the former

Diagnosis

Laboratory Findings

• Elevated serum aminotransferases and conjugated and unconjugated bilirubin levels

• Positive anti-HAV IgM confirms diagnosis, whereas anti-HAV IgG persists after recovery

• Although unusual, hypoalbuminemia, hypoglycemia, and marked prolongation of prothrombin time (international normalized ratio [INR] > 2.0) are serious prognostic findings

Diagnostic Procedures

• Percutaneous liver biopsy is rarely indicated

• "Balloon cells" and acidophilic bodies are characteristic histologic findings

• Liver cell necrosis may be diffuse or focal, with accompanying infiltration of inflammatory cells

• Some bile duct proliferation may be seen in the perilobular portal areas alongside areas of bile stasis

• Regenerative liver cells and proliferation of reticuloendothelial cells are present

Treatment

• No specific treatment measures are required

• Bed rest is reasonable for the child who appears ill

• Sedatives and corticosteroids should be avoided

• During the icteric phase, lower-fat foods may diminish gastrointestinal symptoms but do not affect overall outcome

• Drugs and elective surgery should be avoided

• Hospitalization is recommended for children with coagulopathy, encephalopathy, or severe vomiting

Outcome

Prevention

• Isolation of an infected patient during initial phases of illness is indicated

• However, most patients are noninfectious by the time the disease becomes overt

• Stool, diapers, and other fecally stained clothing should ...