Significance of IgM antibody to hepatitis B core antigen for the differential diagnosis of acute and chronic hepatitis B virus infection and for the evaluation of the inflammatory activity of type B chronic liver diseases

Performance characteristics of microparticle enzyme and chemiluminescence immunoassays for measurement of anti-HBc immunoglobulin M in sera of patients with HBeAg-negative chronic hepatitis B virus infection

The IMx, AxSym, and Architect immunoglobulin M anti-HBc assay systems for detecting hepatitis B virus e antigen-negative chronic hepatitis B virus infection were compared. Despite good intra- and interassay coefficients of variation, significantly different values and low correlation (overestimation by AxSym and underestimation by Architect) were observed. Association and cutoff values for distinguishing patients with viral replication should be established for all methods.

Immunoglobulin M reactivity towards the immunologically active region sp75 of the core protein of hepatitis C virus (HCV) in chronic HCV infection

Serum samples from a cohort of patients with chronic hepatitis C virus (HCV) infection were assayed for IgM anti-HCV/core reactivity with a "site-specific" ELISA, in which the solid phase was charged with the synthetic polypeptide analogue corresponding to the first 75 amino acids of the HCV core antigen (sp75). Thirteen of 24 (54%) patients exhibited IgM anti-sp75 reactivity. Both high-titered (1/16,000-1/32,000) and low-titered (1/1,000-1/4,000) IgM anti-sp75 reactive sera were found. IgM anti-sp75 antibodies persisted in the circulation over a long period in patients with fluctuating abnormal ALT levels. There was a striking association between detection of specific IgM anti-sp75 reactivity and the presence of HCV RNA in serum. Thus 11 of 15 (73%) sera containing HCV RNA also contained IgM anti-sp75 antibodies, while none of the HCV RNA-negative sera were IgM anti-sp75 reactive. Five of 11 patients without detectable levels of specific IgM anti-sp75 antibodies had their ALT levels returned to normal within 8 months to 3 years. Furthermore, a significant correlation was noted between the specific IgM anti-sp75 titers and the concentration of total plasma IgM, indicating that the immunological active region sp75 within the capsid of HCV has the capacity to induce an IgM secretion, which constitutes a substantial portion of the total plasma IgM, in patients with chronic HCV infection.(ABSTRACT TRUNCATED AT 250 WORDS)

Prevalence of IgM anti-HBc among HBsAg carriers in Okinawa, Japan

To evaluate the presence of IgM antibody to hepatitis B core antigen (IgM anti-HBc) in hepatitis B surface antigen (HBsAg) carriers, serial serum specimens of 698 carriers in Okinawa, Japan, from infants to adults, were studied by radioimmunoassay. IgM anti-HBc was detected in 7.6% of these carriers, with no difference between the sexes. The prevalence of IgM anti-HBc was higher in the age groups 0-9, 50-59 and over 60 than in the age group 20-29 and 30-39 years. In hepatitis B e antigen (HBeAg) positive carriers, the prevalence of IgM anti-HBc was 15.4%, a value significantly higher than in the HBeAg-negative carriers at 6.6%. In carriers with liver damage, the prevalence of IgM anti-HBc was 33.3%, a level significantly higher than the 6.3% in carriers without liver damage. However, IgM anti-HBc was detected in 34 carriers with neither HBeAg nor liver damage. These carriers are being closely followed. We discussed the presence of IgM anti-HBc in association with HBeAg or liver damage. The presence of IgM anti-HBc among HBsAg carriers was closely associated with liver damage.

Serial assay for IGM anti-HBc in patients with anti-HBe-positive chronic hepatitis and its significance for long-term prognosis

Serial assays for immunoglobulin M antibody to hepatitis B core antigen (IgM anti-HBc) were performed in 51 patients with antibody to hepatitis B e antigen (anti-HBe) in their sera. IgM anti-HBc was detected periodically and persistently in 8 (53%) of 15 patients with chronic hepatitis whose serum glutamic pyruvic transaminase (GPT) levels were elevated and was not detected in 36 patients with normal serum GPT levels. Antibody to delta agent was not detected in any of the patients. Of the eight patients positive for IgM anti-HBc, four had a high titer of IgM anti-HBc and either developed liver cirrhosis (three cases) or died due to massive hepatic necrosis (one case); the other four showed a low level of IgM anti-HBc and either recovered (two cases) or developed chronic persistent hepatitis (two cases). Of seven patients negative for IgM anti-Hbc, two had a fatty liver, and five, who had a history of blood transfusion, had chronic hepatitis. Thus, even though anti-HBe may be present, if the titer of IgM anti-HBc is high, the histological activity can be expected to increase, and the prognosis will be poor. If the titer of IgM anti-HBc is low, the histological activity may be expected to decrease, and the prognosis may be good. In patients with abnormally high serum GPT but without IgM anti-HBc, another type of hepatitis or a secondary form of liver disease should be considered.