POTENTIAL BENEFITS & HARMS OF THE DRUGS

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POTENTIAL BENEFITS
·        Appropriate management of human immunodeficiency virus (HIV)-infected patients at risk for hepatitis B virus (HBV) infection.
·        In >90% of adult immunocompetent patients, three doses of the hepatitis B vaccine is efficacious and induces protective antibody.
·        Initiation of the HBV vaccine series within 12 to 24 hours of an exposure has been demonstrated to be 70 to 90% effective in preventing HBV infection. The combination of vaccine and hepatitis B immunoglobulin (HBIG) achieves a similar level of efficacy. Among known non-responders to vaccination, one dose of HBIG is 70 to 90% effective in preventing HBV when administered within 7 days of percutaneous HBV exposure, and multiple doses have been shown to be 75 to 95% effective.
·        For neonates born to women who are hepatitis B surface antigen-positive HBsAg(+) and hepatitis Be antigen-negative HBeAg(-), the transmission risk is 10 to 20%. The transmission rate decreases by 85 to 95% when a single dose of HBIG is given within 24 hours of birth and is combined with vaccination beginning within 12 hours of birth.
POTENTIAL HARMS
·        Hepatitis B virus vaccine. Some data suggest that inadvertent initiation of hepatitis B vaccination during acute hepatitis B virus (HBV) infection in human immunodeficiency virus (HIV)-infected persons may actually increase the risk of chronic HBV infection. Prior to the initiation of vaccination, testing to exclude a recent HBV infection is advisable.
·        Interferon-alfa. Interferon-alfa should not be used in patients with decompensated cirrhosis. Interferon alfa is associated with many toxicities (some life-threatening) and should only be used by clinicians who are experienced with its use. Because of its toxicity and limited efficacy, other therapies are considered preferable.
·        Highly active antiretroviral therapy (HAART). Several case reports have described a flare of hepatitis following initiation of HAART with subsequent clearance of hepatitis B surface antigen (HbsAg), which is postulated to reflect improved immune function. The frequency of this phenomenon is unknown, and it should be noted that following initiation of HAART, there are rare cases of fulminant hepatic failure and death. HAART is probably an important management strategy for the co-infected patient; however, it should not be relied on to clear chronic HBsAg carriage. Thus, the clinician should be aware of the potential for significant hepatitis due to immune reconstitution, direct hepatic drug toxicity, or withdrawal of lamivudine.
·        Lamivudine. The alanine transaminase (ALT) levels will frequently rise within 1 to 2 months when lamivudine is used for HBV infection. This rise is transient and should not prompt discontinuation of therapy if the patient is otherwise well. Post-treatment ALT elevations (flares) may occur within 4 months of drug discontinuation. With rare exceptions, these flares do not seem to be clinically severe. The seroconversion from hepatitis Be antigen (HBeAg) to hepatitis Be antibody (HBeAb) may be associated with acute hepatitis that will resolve within a few months.
·        Adefovir. As with lamivudine, severe exacerbations of hepatitis may occur when adefovir is discontinued.