Iatrogenic sensitization by patch testing [Iatrogene sensibilisierung durch epikutantestung]

Abstract

Report on a 54-year-old electrician, who was patch-tested within the scope of a medico-legal evaluation. The patch test readings were carried out routinely after 48 and 72 h. A positive reaction only to turpentine was found. Because of the participation of the patient to an in-patient rehabilitation programme at the university of Osnabrück he was under sustained observation. Nine days after application of the test substances erythema and infiltration in the test area were found. After this period of time it was not possible to definitively assign these reactions to test substances. Within the scope of a new patch test classical allergic crescendo reactions occured to 4,4′-diaminodiphenylmethane and various other para-aminoaryl-compounds, benzoylperoxide, tert.-butylhydrochinone and mix of composites after 48 and 72 h. As during the first patch test late reactions appeared after more than 200 hours and then re-appeared within 48 h on re-testing, an iatrogenic sensitization was assumed. In German law, iatrogenic sensitisation may lead to recognition as an - indirect - occupational illness, if occuring within a medico-legal evaluation procedure and if there is clinical relevance. However, the latter was not the case in our patient. It was concluded that late controls (seven to ten days after application of test substances) seem advisable when patch tests are performed in medico-legal evaluation procedures.