[Atypical onset cryoglobulinemia: case report].

Cryoglobulinemia is a disease mediated by antibodies with the property to precipitate at temperatures below 37°C. It can be distinguished into a primitive form (also referred to as 'essential mixed cryoglobulinemia'), and a secondary form. In the essential mixed variant a key role is played by HCV infection. The pathogenesis of mixed cryoglobulinemia is mediated by immune complexes that are the most important cause of the vasculitic phenomena, typical of the disease. However, the severity of the clinical manifestations is not always related to the serum levels of cryoglobulins and immune complexes. In our case report, a 46-year old man came to our observation with asymmetric diffuse and invalidating arthralgies, with both substitutive and additive behaviour, located at pelvic girdle, inferior limbs and elbows, associated to skin lesion vascultis-like. The remote pathological anamnesis was characterized by a previous surgically treated non-Hodgkin lymphoma, and HCV infection. Despite several attempts were done, it was not possible to reveal cryoglobulins, nor reumatoid factor in the serum. Cryoglobulins resulted positive only after the third day of hospitalization, along with a new fever attack and a worsening of the vasculitic manifestations. In conclusion, this case demonstrated that cryoglobulinemia can occur with a totally atypical sequence of clinical manifestations which can be present before and in absence of the typical laboratory proofs.