Demonstration of reactivity to airborne and food allergens in cutaneous vasculitis by variations in fibrinopeptide A and other blood coagulation, fibrinolysis and complement parameters.
In a 32-year-old woman and a 40-year-old man with cutaneous vasculitis, etiological allergic responses to foods and airborne allergens were found. During provocation tests, observations were made on blood levels of fibrinopeptide A(FPA) and coagulation factors, fibrinogen degradation products (FDP) and serum complement components. Skin biopsies were taken for microscopic and immunofluorescence analysis. In case 1, anaphylactoid allergy to milk and reaginic and anaphylactoid hypersensitivity to grass pollens were found. Dermal provocations with grass pollens gave arthralgia, hematomas, serum C3 fluctuation, factor VII reduction and fibrinolysis. During peroral milk challenge, transient increases in FPA and FDP levels were observed before symptoms appeared. In case 2, anaphylactoid hypersensitivity responses to bacteria, animal danders, foods and pollens were found. Two inhalations with sheep-wool extract resulted in a typical skin eruption. The first also gave an early reduction of C3 and then FPA liberation. Nasal birch-pollen test gave an increase of FPA in the latent period and then typical nodules. At least no low molecular weight FDP were detected during provocations. In patients with vasculitis reactions to exogenous allergens, FPA and FDP estimations after provocations may discriminate harmful from innocuous allergens and reveal individual response patterns in coagulation and fibrinolysis systems.