No abstract

Contact urticaria may be more common than previously believed. Prick tests with HSA-acid anhydride conjugates were a useful test method for detecting immediate sensitization to acid anhydrides. The determination of the specific IgE gave almost equal results. The open application test often had to be performed with the undiluted anhydride product to obtain a positive test result.

Prick tests can be safely used for diagnosing contact urticaria, asthma and rhinitis caused by isocyanates, chloramine-T, persulfates, and chlorhexidine, but the results should be carefully interpreted and related to clinical symptoms and other diagnostic tests.