title: Cutoff levels of immunoglobulin M antibody against viral core antigen for differentiation of acute, chronic, and past hepatitis B virus infections.
abstract: The titer of antibody against core antigen of hepatitis B virus in the immunoglobulin M class (IgM anti-HBc) was determined by an IgM capture assay of reduced sensitivity (30 arbitrary units). The distribution of titers among 235 acute hepatitis patients who were hepatitis B surface antigen (HBsAg) positive suggested that 600 U forms a lower cutoff value for acute hepatitis B. Clinically apparent cases of acute hepatitis with high IgM anti-HBc and without HBsAg were rare (2.6%). Acute, non-B hepatitis in HBsAg carriers was more frequent (9.4%). In chronic hepatitis B, 39% of 174 biopsy-proven cases had moderate titers of 30 to 600 U, whereas healthy HBsAg carriers were rarely (4/84) positive. In mild or inapparent infections without HBsAg, titers were between 50 and 400 U. Thus, sufficiently accurate and sensitive quantitation of IgM anti-HBc allows for differentiation of acute and nonacute hepatitis B virus infection in acute hepatitis, partial differentiation between clinically symptomatic and asymptomatic chronic infections, and identification of recent subclinical infections.
mesh_terms: D000208:Acute Disease; D002908:Chronic Disease; D006509:Hepatitis B / Q000175:diagnosis* / Q000276:immunology; D006510:Hepatitis B Antibodies / Q000032:analysis*; D006512:Hepatitis B Core Antigens / Q000276:immunology*; D006514:Hepatitis B Surface Antigens / Q000032:analysis; D006801:Humans; D007075:Immunoglobulin M / Q000032:analysis*
chemical_list: D006510:Hepatitis B Antibodies; D006512:Hepatitis B Core Antigens; D006514:Hepatitis B Surface Antigens; D007075:Immunoglobulin M