Evaluation of contact sensitivity in patients with isolated itching of the external auditory canal.

Objective: This study was designed to demonstrate the frequency of sensitivity to European standard patch test allergens in patients with isolated itching of the external auditory canal (EAC).
Study Design: A prospective case-control study.
Methods: Fifty-six female patients with the complaint of recurrent EAC itching and 30 female controls without pruritis of the ears were patch-tested with 25 allergens of the European standard series.
Results: Twenty-four patients (25.5%) had one or more positive patch test reactions. In 21.4% of patients, nickel sulphate was the most frequent sensitizer, but there was no statistically significant difference in the nickel sensitization rate between patients and controls (p > .05). Sensitivity rates were much lower for the other allergens. There was no association between contact sensitivity to fragrances and to preservatives and patients with pruritis of the ears.
Conclusion: Our results do not demonstrate that most patients with pruritic ears probably suffer from allergic contact dermatitis.