Hepatitis E
Hepatitis E is an RNA virus that has 1 serotype and 4 genotypes. Its epidemiology is similar to that of hepatitis A. It is the most common waterborne illness in the world. The incubation period varies from 21 to 56 days. This disease is quite rare in the United States but is endemic in developing nations. In those countries, maternal infection has an alarmingly high mortality rate (5%–25%). For example, in Bangladesh, hepatitis E is responsible for more than 1,000 deaths per year in pregnant women. When hepatitis E is identified in more affluent countries, the individual cases and small outbreaks usually are linked to consumption of undercooked pork or wild game.1,15-17
The clinical presentation of acute hepatitis E also is similar to that of hepatitis A. The usual manifestations are fever, malaise, anorexia, nausea, right upper quadrant pain and tenderness, jaundice, darkened urine, and clay-colored stools. The most useful diagnostic tests are serologic detection of viral-specific antibodies (positive IgM or a 4-fold increase in the prior IgG titer) and PCR-RNA.1,17
Hepatitis E usually does not cause a chronic carrier state, and perinatal transmission is rare. Fortunately, a highly effective vaccine was recently developed (Hecolin, Xiamen Innovax Biotech). This recombinant vaccine is specifically directed against the hepatitis E genotype 1. In the initial efficacy study, healthy adults aged 16 to 65 years were randomly assigned to receive either the hepatitis E vaccine or the hepatitis B vaccine. The vaccine was administered at time point 0, and 1 and 6 months later. Patients were followed for up to 4.5 years to assess efficacy, immunogenicity, and safety. During the study period, 7 cases of hepatitis E occurred in the vaccine group, compared with 53 in the control group. Approximately 56,000 patients were included in each group. The efficacy of the vaccine was 86.8% (P<.001).18
Hepatitis G
Hepatitis G is caused by 2 single-stranded RNA viruses that are virtually identical—hepatitis G virus and GB virus type C. The viruses share approximately 30% homology with hepatitis C virus. The organism is present throughout the world and infects approximately 1.5% to 2.0% of the population. The virus is transmitted by blood and sexual contact. It replicates preferentially in mononuclear cells and the bone marrow rather than in the liver.19-21
Hepatitis G is much less virulent than hepatitis C. Hepatitis G often coexists with hepatitis A, B, and C, as well as with HIV. Coinfection with hepatitis G does not adversely affect the clinical course of the other conditions.22,23
Most patients with hepatitis G are asymptomatic, and no treatment is indicated. The virus can cause a chronic carrier state. Perinatal transmission is distinctly uncommon. When it does occur, however, injury to mother, fetus, or neonate is unlikely.1,24
The diagnosis of hepatitis G can be established by detection of virus with PCR and by the identification of antibody by enzyme immunoassay. Routine screening for this infection in pregnancy is not indicated.1,2
CASE Resolved
Hepatitis B is highly contagious and can be transmitted from the patient to her sexual partner and neonate. Testing for hepatitis B surface antigen and antibody is indicated in her partner. If these tests are negative, the partner should immediately receive hepatitis B immune globulin and then be started on the 3-dose hepatitis B vaccination series. The patient’s newborn also should receive hepatitis B immune globulin within 12 hours of delivery and should receive the first dose of the hepatitis B vaccine prior to discharge from the hospital. The second and third doses should be administered 1 and 6 months after delivery.
The patient also should have the following tests:
• liver function tests
-serum transaminases
-direct and indirect bilirubin
-coagulation profile
• hepatitis D antigen
• hepatitis B genotype
• hepatitis B viral load
• HIV serology.
If the hepatitis B viral load exceeds 1 million copies/mL, the patient should be treated with tenofovir 200 mg daily from 28 weeks’ gestation until delivery. In addition, she should be referred to a liver disease specialist after delivery for consideration of treatment with directly-acting antiviral agents. ●