Cryofibrinogenaemia: a study of 49 patients

The purpose of this study was to characterize the clinical features and com ponents of 30 patients with isolated cryofibrinogen (CF) versus those of 19 patients with combined CF and cryoglobulins (CG). Secondary forms of cryof ibrinogenaemia associated with collagen disorders, infectious or malignant diseases, were significantly more frequent in patients with combined CF and CG than those with isolated CF (79 versus 47%, P = 0.02). Both groups of C F patients presented predominantly cutaneous symptoms (77% in isolated CF; 58% in combined CF + CG), and less frequently venous and/or arterial thromb osis (13% in isolated CF; 3% in combined CF + CG). Patients with idiopathic forms of CF, and particularly those without CG, suffered essentially from recurrent painful skin ulcers, mainly triggered by cold exposure. Patients with isolated CF had higher mean plasma concentrations of CF than those wit h combined CF + CG (1.61 +/- 1.26 versus 0.82 +/- 1.18 g/l, respectively; P = 0.004), but there was no correlation between the CF plasma level and eit her the severity of symptoms or the sensitivity to cold. In patients with i solated CF, fibronectin was suggested (by precipitation analysis) to be a m ajor component of the cryoprecipitate, whereas immunoglobulins were rarely present (in only three out of 30 patients). By contrast, in the majority of patients (78%) with combined CF and CG, the CF consisted mainly of immunog lobulins of the same class as those characterizing the associated CG. Analy sis of the CG precipitate revealed the presence of fibronectin but not fibr inogen, alpha(1)-antitrypsin and alpha(2)-macroglobulin. In conclusion, iso lated and combined cryofibrinogenaemia are associated with different clinic al signs requiring different clinical management, but there is no evidence as yet for a causal role of the cryoprecipitates in the differences observe d.