Comparison of skin-prick test and specific serum IgE determination for the diagnosis of latex allergy.

BACKGROUND: Latex IgE-mediated hypersensitivity has been recognized as an international health problem. However, there is poor information on the efficiency of the diagnostic methods available.

OBJECTIVE: The purpose of this study was to specify the efficiency of several diagnostic methods for latex allergy.

METHODS: We designed a prospective study involving 50 adult patients with latex allergy, as diagnosed by a suggestive clinical history and a positive skin-prick test (SPT) to a latex extract. One control group of 50 subjects paired for age, sex, total IgE levels and latex exposure, and another control group of 30 subjects with pollen allergy were used. A low-ammoniated natural-latex and several glove-latex extracts were elaborated. SPTs with these extracts, as well as with four different commercial-latex extracts were performed. Latex-specific serum IgE was determined by the CAP and the AlaSTAT methods.

RESULTS: Diagnostic sensitivity was 98% for the natural-latex extract SPT, from 90% to 98% for the commercial-latex extract SPT, and from 64% to 96% for the glove-latex extract SPT. Diagnostic specificity of SPT was 100%, and no severe adverse reactions were observed during skin testing. With respect to the latex-specific serum IgE determinations, sensitivity was 86% for the CAP system and 84% for the AlaSTAT assay, and specificity was dependent on the population considered.

CONCLUSION: SPT with natural latex extracts has shown a diagnostic efficiency close to 100%, significantly higher than that of latex-specific serum IgE determination.