Immunofluorescent studies of the skin in mixed cryoglobulinaemia and Schönlein-Henoch purpura.

Immunofluorescence investigations in patients with mixed cryoglobulinaemia, Schönlein-Henoch purpura and purpuric allergic reaction with disseminated intravascular coagulation have been performed. In the lesional skin from 8 patients with mixed cryoglobulinaemia, granular vascular deposits of immunoglobulins of the same classes as those of the circulating cryoglobulins were detectable in all cases; complement and fibrinogen were concomitantly present. In the unaffected skin, IgM and complement were detected in the walls of the capillaries. In the early purpuric lesions from 6 patients with Schönlein-Henoch syndrome and from a patient with diseeminated vascular coagulation from acute allergic reaction to phenylbutazone, deposits of fibrinogen occurred mainly in the vessel walls.