Therapeutic measures after hepatitis B virus infection: postexposure prophylaxis.

Hepatitis B postexposure prophylaxis is here reviewed. Every contact with hepatitis B virus can cause an infection which may be either acute, subclinical, or progressive, the latter potentially leading to chronic liver disease and hepatocellular carcinoma. Direct injection of large quantities of HBsAg-positive blood is almost invariably contagious. While casual person-to-person contact rarely causes disease, the multiplicity of exposure in the hospital environment or the home increases the risk for transmission. Several studies have shown that postexposure prophylaxis using passive immunization with specific hepatitis B antibodies is possible. Hepatitis B immune globulin (HBIG) with a minimum titre of 100 IU/ml should be used. In practice, most preparations contain 500 IU/ml. The use of HBIG post-exposure prophylaxis should be limited to needlestick injury, sexual exposure, and perinatal contact of neonates with HBsAg-positive mothers. Routine vaccination as an adjunct to HBIG administration is recommended. HBIG does not decrease the immunogenic properties of the vaccine provided that the injection is not made at the same site. With increasing use of hepatitis B vaccines, the need for therapeutic intervention will hopefully be considerably diminished. Prevention rather than therapy should be stressed.