HCV and monoclonal gammopathies.

OBJECTIVE

To determine the prevalence of antibodies against HCV in monoclonal gammopathies with and without cryoglobulinemic activity.

METHODS

201 patients were divided into two groups: (I) 94 patients with monoclonal gammopathies with cryoglobulinemic activity, and (II) 107 with monoclonal gammopathies without cryoglobulinemic activity. Cryoglobulins were characterized by immunofixation; HCVAb were detected using second-generation ELISA and RIBA methods; in 38 cases the presence of HCV in peripheral blood mononuclear cells was evaluated by PCR.

RESULTS

The HCVAb prevalence, as evaluated by RIBA, in Group I was 69.1% while in Group II it was only 14.9%. Histological and immunohistochemical study of the bone marrow in Group I patients frequently showed signs of nodular B-cell clonal expansion.

CONCLUSIONS

Our data confirm the existence of a close correlation between HCV infection and the monoclonal gammopathies with cryoglobulinemic activity. HCV-positive cryoglobulinemic is characterized by self-limiting IgM monoclonal expansion associated with histological aspects of bone marrow lymphoid nodules that do not expand in the course of the disease like classic evolving lymphoproliferative processes.