Hepatitis B

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Description

Hepatitis B virus (HBV) infection, caused by a DNA virus, is often transmitted by body fluids (blood, semen, and vaginal secretions). HBV is a serious global health care concern due to the spectrum of liver disease. It can cause ranging from acute hepatitis to cirrhosis and/or hepatocellular carcinoma (HCC).

Epidemiology

Incidence

  • The highest HBV infection rate by age group is among adults aged 30 to 49 years, accounting for 46% of newly reported chronic cases (1).
  • Predominant sex: fulminant HBV: male > female (2:1)
  • Around 2,000 confirmed new cases of hepatitis B in the United States every year. Many more (>10,000) are believed to go unconfirmed each year.
  • Lower incidence in the United States compared to Asia and Africa due to better access to health care, use of vaccinations, and preventive measure.

Prevalence

  • In 2023, 17,650 newly identified cases of chronic hepatitis B were reported to CDC (~6.1/100,000).
  • New cases of chronic hepatitis B among non-Hispanic Asians/Pacific Islanders (19/100,000) 10× greater than identified cases among non-Hispanic White persons (1.9/100,000)

Etiology and Pathophysiology

DNA virus of the Hepadnaviridae family; two modes of transmission:

  • Horizontal: mucosal surface contact with infectious bodily fluids
  • Vertical: maternal-to-newborn perinatal

Genetics

Family history of HBV and/or HCC

Risk Factors

  • Universal one time screening in all patients aged >18 years (regardless of risk)
  • Universal screening in pregnancy
  • Screen the all high-risk groups.
  • Household or sexual contacts with hepatitis B; persons born in regions with increase (>2%) prevalence (Asia, Africa, Eastern Europe); HIV- and HCV-positive patients; persons born in the United States who were not vaccinated as infants or whose parents are from regions of high prevalence; individuals with chronic liver disease; pregnant persons; persons with a history of incarceration
  • Additional risk factors:
    • Donors and recipients of blood/products; persons on hemodialysis or immunosuppressive therapy; needle stick/occupational exposure; intranasal drug use; body piercing/tattoos; survivors of sexual assault; infants born to mothers positive for hepatitis B surface antigen (HbsAg)
  • If HBsAg screening is positive, test for antibodies to HBsAg (anti-HBs) and hepatitis B core antigen (anti-HBc) to distinguish between infection and immunity. Vaccinate if seronegative.

Pediatric Considerations

  • Shorter acute course; fewer complications
  • 90% of vertical/perinatal infections become chronic.

Pregnancy Considerations

  • Screen for HBsAg at first prenatal visit.
  • If HBsAg positive, obtain HBV DNA.
  • Consider treating patients with high viral load at 28 weeks or history of previous HBV-positive infant with oral nucleoside/nucleotide medication beginning at 28 to 32 weeks to reduce perinatal transmission. Infants born to HBV-infected mothers require hepatitis B immune globulin (HBIG) and HBV vaccine within 12 hours of birth.
  • Breastfeeding safe if HBIG and HBV vaccines are administered and the areolar complex is without fissures or open sores. Avoid oral nucleoside/nucleotide medications during lactation.
  • Continue treatment while pregnant to decrease viral load and decrease the chances of vertical transmission.

General Prevention

  • Vaccination
    • Three IM injections at 0, 1, and 6 months in infants or healthy adults
    • Indicated for all medically stable infant weighing 2,000 g (4 lb, 6 oz) or more within 24 hours of birth; unvaccinated children and adolescents aged <19 years; all adults aged 19 to 59 years; adults aged ≥60 years with risk factors or who request vaccination; health care and public safety workers, sexual contacts, and household contacts of HBsAg carriers
    • CDC does not recommend administration of more than 2 complete hepatitis B series except for certain cases related to patients on hemodialysis.
  • Other preventive measures
    • Proper hygiene/sanitation by health care workers, intravenous drug users, and tattoo/piercing artists
    • Safe sexual practices (condoms)
    • HBsAg carriers cannot donate blood or tissue.
    • Postexposure (e.g., needle stick):
      • HBIG 0.06 mL/kg in <24 hours in addition to vaccination (no more than 7 days after exposure)
      • Second dose of HBIG should be administered 30 days after exposure.

Commonly Associated Conditions

  • HIV, hepatitis C coinfection
  • Extrahepatic manifestations:
    • Serum sickness-like syndrome (fever, erythematous rash, myalgias, arthralgias, fatigue); glomerulonephritis (membranous or membranoproliferative glomerulonephritis, IgA-mediated nephropathy)
    • Polyarteritis nodosa (primary systemic necrotizing vasculitis, high fever, weakness, malaise, loss of weight and appetite); cryoglobulinemia (Raynaud phenomenon, arthritis, sicca syndrome)
    • Neurologic/psychological condition (Guillain-Barré syndrome, altered mental status, depression/psychosis)

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