Hepatitis B Virus

Hepatitis B virus (HBV) is a DNA virus transmitted primarily through blood (percutaneous and permucosal routes), semen, and vaginal secretions. It can be transmitted through mucous membranes and breaks in the skin. Hepatitis B has a long incubation period (1 to 6 months). It replicates in the liver and remains in the serum for long periods, allowing transmission of the virus. Those at risk include all health care workers, patients in hemodialysis and oncology units, sexually active homosexual and bisexual men, and IV drug users. About 10% of patients progress to a carrier state or develop chronic hepatitis. Hepatitis B remains a major worldwide cause of cirrhosis and hepatocellular carcinoma.

• Symptoms may be insidious and variable; subclinical episodes frequently occur, but fever and respiratory symptoms are rare; some patients have arthralgias and rashes.
• Loss of appetite, dyspepsia, abdominal pain, general aching, malaise, and weakness may occur.
• Jaundice may or may not be evident. With jaundice, there are light-colored stools and dark urine.
• Liver may be tender and enlarged; spleen is enlarged and palpable in a few patients. Posterior cervical lymph nodes may also be enlarged.

HBV is a DNA virus composed of the following antigenic particles:

• HBcAg—hepatitis B core antigen (antigenic material in an inner core)
• HBsAg—hepatitis B surface antigen (antigenic material on the viral surface, a marker of active replication and infection)
• HBeAg—an independent protein circulating in the blood
• HBxAg—gene product of X gene of HBV DNA
• Each antigen elicits its specific antibody and is a marker for different stages of the disease process:
• anti-HBc—antibody to core antigen of HBV; persists during the acute phase of illness; may indicate continuing HBV in the liver
• anti-HBs—antibody to surface determinants on HBV; detected during late convalescence; usually indicates recovery and development of immunity
• anti-HBe—antibody to hepatitis B e-antigen; usually signifies reduced infectivity
• anti-HBxAg—antibody to the hepatitis B x-antigen; may indicate ongoing replication of HBV

HepBsAg appears in the blood of up to 80% to 90% of patients. Additional antigens help to confirm the diagnosis.

• Alpha-interferon has shown promising results.
• Lamivudine (Epivir) and adefovir (Hepsera) are useful agents.
• Bed rest and restriction of activities are advisable until hepatic enlargement, elevation of serum bilirubin, and elevation of liver enzymes have disappeared.
• Adequate nutrition should be maintained; restrict proteins when the ability of the liver to metabolize protein byproducts is impaired.
• Administer antacid and antiemetic agents for dyspepsia and general malaise; avoid all medications if patient is vomiting.
• Provide hospitalization and fluid therapy if vomiting persists.

Gerontologic Considerations

The immune system is altered in older adults, which may be responsible for the increased incidence and severity of hepatitis B among this demographic and the increased incidence of liver abscesses secondary to decreased phagocytosis by the Kupffer cells. The older patient with hepatitis B has a serious risk of severe liver cell necrosis or fulminant hepatic failure, particularly if other illnesses are present.

Convalescence may be prolonged and recovery may take 3 to 4 months; encourage gradual activity after jaundice is completely clear.

• Identify psychosocial issues and concerns, particularly the effects of separation from family and friends if the patient is hospitalized; if not hospitalized, the patient will be unable to work and must avoid sexual contact.
• Include family in planning, to help reduce their fears and anxieties about the spread of the disease.
• Educate patient and family in home care and convalescence.
• Instruct patient and family that adequate rest and nutrition are essential.
• Inform family and intimate friends about risks of contracting hepatitis B.
• Arrange for family and intimate friends to receive hepatitis B vaccine or hepatitis B immune globulin as prescribed.
• Caution patient to avoid drinking alcohol and eating raw shellfish.
• Educate family that follow-up visits by home care nurses are indicated to assess progress and understanding, reinforce teaching, and answer questions.
• Encourage patient to use strategies to prevent exchange of body fluids, such as abstinence or using condoms.
• Emphasize importance of keeping follow-up appointments and participating in other health promotion activities and recommended health screenings.