Lesson from an intriguing case of cryoglobulinemia.

Cryoglobulinemia is a pathological condition usually associated with hepatitis C virus (HCV) chronic liver disease and less commonly with autoimmune or lymphoproliferative disorders. The possible association of cryoglobulinemia with hepatitis B virus (HBV) infection is not widely accepted. In our patient, serum negativity for HCV markers initially led us to consider two other causes of cryoglobulinemia. Myelodysplastic disorders were excluded on the basis of hematological studies, while serum markers for active HBV infection were positive. Surprisingly, the detection of HCV RNA in the cryocrit, even in the absence of anti-HCV antibodies, suggested a pathogenetic role of HCV in this case of cryoglobulinemia. Negative "first level" tests for HCV in the serum do not completely exclude HCV involvement in the pathogenesis of cryoglobulinemia. Analysis of the cryoprecipitate is always essential for diagnosis.