Reactivity of tixocortol pivalate-positive patients in intradermal and oral provocation tests.

Pivalone/tixocortol pivalate commonly yields positive reactions in the patch test series. The clinical relevance of these positive reactions was investigated in more detail. In the standard patch test series 5.6% (73 of 1306) of the patients were positive to corticosteroids, 5.2% to 0.1% tixocortol pivalate in ethanol (Pivalone nasal spray diluted 1:10) and 2.3% to 1% hydrocortisone butyrate in ethanol. Some of the patients were tested in parallel with Pivalone and 1% tixocortol pivalate in petrolatum. The former test reagent yielded some false-positive reactions, whereas with the latter, some allergic responses were missed. Intradermal tests with the succinate esters of hydrocortisone, methylprednisolone and prednisolone were performed with 52 patients positive to Pivalone. Of these 76.9% (40 of 52) were positive in the intradermal tests; 38 to hydrocortisone, 35 to methylprednisolone and 30 to prednisolone. Twelve patients who had been positive in the intradermal tests were challenged orally with corticosteroids and they all showed positive reactions to hydrocortisone, methylprednisolone or prednisolone. The patients developed localized reactions at the sites of previous eczema or positive skin tests or diffuse erythema or exanthema. The oral doses of hydrocortisone eliciting positive delayed skin reactions ranged from 20 to 200 mg. Reactivity to tixocortol pivalate is closely related to sensitivity to hydrocortisone, methylprednisolone and prednisolone, but high oral doses of these corticosteroids may be required to produce allergic symptoms.