Contact urticaria from latex in healthcare workers.
BACKGROUND: Latex allergy is an important medical problem for an increasing number of patients. It has been documented as causing immediate hypersensitivity reactions ranging from mild urticaria to life-threatening anaphylaxis after cutaneous, mucosal or visceral exposure. Recent studies in northern Europe and the USA suggest that between 2.8 and 16.9% of healthcare workers are affected by latex hypersensitivity type I reactions. OBJECTIVES: To test the prevalence of contact urticaria from latex gloves in a group of healthcare workers, to examine the factors associated with latex allergy and to evaluate some diagnostic methods used in latex allergy. METHODS: A total of 929 employees of the surgical units who used latex gloves on a regular basis, at least once a day, were invited to participate in this study including administration of a questionnaire, a prick test with a commercial extract of latex, a prick test with latex glove eluate, a use test, RAST and an immunoblotting system; moreover, a prick test with a group of common inhalant allergens and a prick-by-prick test with fresh fruit (banana, kiwi, avocado, chestnut) were employed. RESULTS: Of the 929 staff sent questionnaires, 313 (33.5%) replied; of those who responded, 118 gave a history of hand problems such as itch, erythema, wheals when wearing gloves, dryness and irritation most marked on the backs of the hands. Among these 118 workers, 16 refused skin testing and examination of blood, so 102 subjects were studied for latex allergy; 21/118 (17.8%) healthcare workers were found to be latex allergic. Eighty-one staff members gave a history of hand problems worsened by wearing gloves but were not latex allergic on testing. Those healthcare workers who completed the questionnaire and answered negatively (195/313) were not tested for latex allergy. Prick tests with the commercial solution were positive in 11 of the 21 subjects studied; prick tests with the eluate of glove, RAST and the use test were positive in all workers; 10 of the 21 sera showed positive immunoblot results. Atopy and a preexisting irritant contact eczema of the hands were present in a high percentage of the workers. CONCLUSION: In this study of healthcare personnel, we found that allergic contact urticaria from latex was present in 21 workers of the 313 (6.7%) who responded to the questionnaire and of the 102 (20.5%) who were tested for latex allergy. Atopy and irritant contact eczema of the hands were frequent in these subjects. Skin prick testing with latex glove eluate and the use test seem to be more sensitive than in vitro testing, particularly immunoblotting, and are biologically more relevant; skin testing with glove eluate must be preferred to testing with a commercial extract.