Sensitization to resorcinol due to an anti-wort ointment: unusual systemicclinical features and occurrence.

Background, Resorcinol is a rare sensitizer. In Lorraine, where it is used in high concentrations in an anti-wart ointment, this molecule has induced many cases of allergy. The purpose of this study was to describe clinical f eatures in patients sensitized to resorcinol, to determine the incidence of sensitization in Lorraine and ascertain the occurrence of cross reactions with other phenolic pro-haptens. Patients and methods. The files of all patients sensitized to resorcinol we re studied from 1992 to 1999. Over a to-month period, 983 consecutive patie nts underwent our standard patch tests where we included resorcinol (i p. t oo in petrolatum). Go-sensitization with other pro-haptens was studied in a ll sensitized patients. Results. Sensitization to resorcinol was observed in 0.5 p, too of the 983 consecutively tested patients. Contact sensitization was found in 24 patien ts, who ail but one had previously used the anti-wart ointment containing r esorcinol. All developed contact eczema on the site of application of the o intment, with generalized urticaria (4 cases), pompholyx (1 case), and gene ralized papulo-vesicular rash with pompholyx (6 cases). Postive patch tests were observed with resorcinol monobenzoate (15/19 cases), pyrocatechol (7/ 14 cases), pyrogallol (9/19 cases), salicylaldehyde (2/17 cases), and hydro quinone (6/17 cases). Negative patch tests were obsserved with phenysalicyl ate, hexylresorcinol, or fluoresceine. Conclusion, Resorcinol shold not be applied in high concentrations as it ca n provoke generalized sensitization and co-sensitization with other pro-hap tens.