Cryoglobulinemia in acute type-A hepatitis.

Serum cryoglobulins were detected in 18 of 19 patients with type-A, and six of eight with type-B hepatitis. The predominant immunoglobulin in the cryoprecipitates was polyclonal IgM. Patients with type-A hepatitis had a significantly higher mean serum level of cryoglobulins when compared to those with type-B (106.9 vs. 20.5 micrograms/ml). IgM anti-hepatitis-A virus activity was detected in all cryoprecipitates obtained from hepatitis-A patients. Cryoglobulinemia in these patients was transient, associated with disease activity and accompanied by a marked increase in serum level of IgM. These findings are compatible with a recent hypothesis, which predicts the appearance of cryoglobulins under circumstances of enhanced stimulation of B cells in the presence of defective clearance of desialylated glycoproteins by their specific liver receptors.