Induction of lesions of dermatitis herpetiformis by autologous serum.
Raktažodžiai
Santrauka
In the present study various factors which contribute to the initiation of lesions in dermatitis herpetiformis (DH) were examined. Thirty-one patients with DH, seven with bullous pemphigoid, two with linear IgA disease and two healthy subjects were studied either before starting treatment or after stopping dapsone for up to 5 days. Intradermal inoculation of freshly prepared autologous serum was followed after 18-24 h by the formation of DH-like lesions in 24/31 DH patients. The lesions were erythematous papules, often with vesicles and microscopically showed papillary tip microabscesses. Serum-induced formation of lesions only occurred in patients with active DH with some spontaneous lesion formation: it did not occur in any of the non-DH controls. The formation of lesions was dose-related, declining proportionately with dilution of the serum down to 1/16. Plasma prepared by various methods of anticoagulation (heparin, citrate, EDTA) caused lesser reactions, while addition of heparin or epsilon-amino caproic acid (EACA), but not citrate, to serum substantially inhibited the formation of lesions. This suggested the responsible factor might be a protease. Other vasoactive agents including histamine (1-4 micrograms) and compound 48/80 (1-5 micrograms) caused normal immediate wealing. DH-like lesions occurred in only one of 13 subjects challenged with histamine and two of nine challenged with 48/80. In all these, autologous serum elicited large vesicular responses. There is a factor(s) in serum in DH which can initiate the formation of lesions. This factor appears to be activated by clotting and can be inhibited by heparin and EACA, suggesting it may be a protease.