Aplastic anemia associated with type A viral hepatitis--possible role of T-lymphocytes.

Posthepatitic aplastic anemia (PHAA) is rather uncommon. Most reported cases have developed after non-A, non-B or B type hepatitis. The only case of PHAA occurring after hepatitis A reported so far, was described by Smith et al., who diagnosed it by the long-term elevation of IgG-class antibody in response to hepatitis A virus. Recently, the detection of IgM-class antibody specific against hepatitis A virus (IgM anti-HAV) has been commonly employed for precise diagnosis of hepatitis A. The case reported here is the first case of PHAA occurring after hepatitis A to be diagnosed by radioimmunoassay of IgM anti-HAV. Furthermore, evidence is presented suggesting that the PHAA may have been an immune-related response. Addition of the patient's peripheral T-lymphocytes to cultures of her own bone marrow cells resulted in a reduction in the number of colony-forming units in culture (CFU-C).