Reactions to corticosteroids: some new aspects regarding cross-sensitivity.

Patch test results obtained with corticosteroid allergic patients tested with a large corticosteroid series validated the earlier classification of corticosteroid molecules in four groups of cross-reacting molecules: i.e., group A (hydrocortisone type), group B (acetonides), group C (betamethasone type-non esterified) and group D (esters). The latter group can now be subclassified into 2 groups, i.e., group D1 (halogenated and with C16 substitution) and group D2 (the "labile" prodrug esters without the latter characteristics).