The prevalence of latex allergy among a nursing population.

Abstract

Following implementation of universal precautions in 1987, latex glove production has increased over 100%. Consequently, the number of adverse reactions to latex products have escalated. Nurses have been recognized as being at increased risk for latex allergy, but most studies lack systematic investigation of pre-defined populations by including only volunteer nurses, thereby predisposing the studies to selection bias. The three-fold purpose of this study was to determine the prevalence of latex allergy among registered nurses at a large urban hospital using an in vitro assay to detect anti-latex immunoglobulin E (IgE) antibodies, to examine the relationship between self-administered questionnaire responses concerning symptoms associated with latex exposure and in vitro testing, and to identify factors associated with latex allergy. The sample included inpatient nurses employed on May 5, 1993. Of the target population (n = 818), 741 (90.6%) nurses completed questionnaires and donated serum samples. Sixty-five (8.9%, 95% confidence interval (CI) 6.7, 12.9) nurses were classified as positive for latex allergy, defined by an anti-latex IgE concentration $\ge$0.35 international units/milliliter. Sixty per cent (n = 448) of the nurses reported at least one symptom, and of these, only 12.5% had positive sera results. Red itchy skin was not an indicator of latex positivity (positive predictive value (PPV) = 8.1%), but the presence of conjunctivitis and red itchy skin increased the PPV to 21.1%. Prevalence of latex allergy was not associated with age, sex, years of nursing clinical experience or nursing specialty. Latex allergy prevalence was higher in nonwhites (OR = 2.4, 95% CI 1.4, 4.1), and was also associated with history of atopy (OR = 3.0, CI 1.7, 5.2), reported symptoms with latex contact (OR = 4.5, CI 2.1, 9.9), allergies to banana (OR = 3.5, CI 0.8, 12.0), avocado (OR = 10.9, CI 1.4, 82.2), and penicillin (OR = 2.6, CI 1.3, 5.1). After adjusting for age and sex by logistic regression, race, reported histories of red itchy skin, conjunctivitis, hay fever, and allergies to ragweed, penicillin and avocados were significantly associated with latex allergy. The results indicate that among inpatient nurses, latex is an allergen. Furthermore, questionnaires are unreliable in predicting latex positivity and must be supported by diagnostic testing. Associations found between characteristics and latex allergy prevalence suggest possible risk factors. Determining the incidence of and risk factors for latex allergy warrants prospective epidemiologic investigations.