Abnormal cutaneous reactions in dermatitis herpetiformis.

In 94% of the patients with dermatitis herpetiformis, a locally applied ointment with an ester of nicotinic acid (Trafuril) induced an abnormal reaction with erythema, edema, papules, and often vesicles. The appearance of the reaction to Trafuril is similar to DH lesions. It differs markedly from the reactions to iodide where, as a rule, only one large blister results. The reaction is most pronounced 12-24 hours after application of Trafuril. The reactivity is strongest in the predilection areas for dermatitis herpetiformis. Strongly increased reactivity to Trafuril in DH is induced by pretreatment with streptokinase, streptokinase-streptodornase, or urokinase. Diminished reactivity to Trafuril is seen after pretreatment with injections of Compound 48/80, tranexamic acid, cromoglycate, or application of fluocinolone-acetonide, as well as after stroking the skin.