The prevalence of latex allergy in children seen in a university hospital allergy clinic

Abstract

Natural rubber latex allergy is responsible for a wide spectrum of clinical symptoms, ranging from rhinoconjunctivitis to severe anaphylaxis, in both adults and children. An association between allergy to latex and allergy to various fruits has been reported. This study investigated the prevalence and clinical significance of latex sensitization in children seen in a university hospital allergy clinic. A total of 453 consecutive children were screened in a 7-month period. A detailed clinical history with particular attention to the past surgical history and the eventual presence of latex- or food-induced allergic symptoms was obtained. Skin prick tests (SPT) for the more important inhalant allergens and foods were performed on all children. In patients with positive latex SPT, latex challenge and additional SPT for some fresh foods (avocado, pineapple, apricot, grape, banana, pear, apple, orange, almond, and chestnut) were also performed. RAST for the same food antigens, as well as patch test with latex and a standard battery of contact allergens, was also done. Of 326 atopic children, 10 (3%) presented positive skin test to latex, but only five (1.5%) also had a positive clinical history to latex exposure. Latex challenge was positive in 3/9 positive-latex-SPT children. None of the nonatopic children had positive skin test to latex or symptoms to latex exposure. A history of previous surgery was found in 5/10 positive-latex-SPT children, in 63/316 negative-latex-SPT atopic children (P < 0.05), and in 23/127 nonatopic children. RAST to latex was positive in 5/10 positive-latex-SPT children. Associated fruit-specific IgE (SPT and/or RAST) were found in all latex-symptomatic children and in 2/5 latex-asymptomatic children. Apple, kiwi, and chestnut were the most common SPT-positive foods. Only one patient with clinical allergy to latex and positive skin tests to fruits had a history of clinical symptoms after ingestion of kiwi and orange. The natural history of the positive-latex-SPT children without clinical reactions to latex exposure and the clinical significance of the association of latex and fruit sensitivity require further studies.

Diagnostic Value of Three Different Latex Extracts

“…Moreover, comparing the IB profiles of SL and RPE extracts we can observe that, in some cases, the results were different (e.g. : sera 5,6,7,8,9,10,13,15) suggesting that different allergens or, alternatively, different concentrations of the same allergen can be contained in the extracts under consideration. This difference appears evident considering the IE profile of sera 4, 10 and 15.…”

“…The complex procedure required to obtain them, the variability of the amount of latex proteins present, and the high risk of appearance of systemic reactions during skin tests have discouraged allergen manufacturers from using them in the preparation of a diagnostic commercial latex extract (9). Ammoniated and nonammoniated latex (AL and NAL respectively) have been introduced in the preparation of SPT extracts and used in the diagnosis oflatex allergy (10)(11)(12).…”

Latex Allergy in Children

“…In a recent study, 609 sera of atopic and nonatopic children (mean age 4.5 years) were screened for specific IgE to latex and it was found that 20.8% of the atopic (and 0.3% of the nonatopic) children were sensitized to latex [11]. Other authors found lower values for atopic children: Novembre et al [12]reported on 3% of atopic children (mean age 7 years) being sensitized to latex. This discrepancy may be explained by the patient characteristics seen in university allergy clinics; in our study there was a high degree of children with atopic dermatitis among children with a positive provocation test (75%), and atopic dermatitis seems to present a special risk group.…”

“…Although a detailed history is important and the question ‘What happens when you blow up a balloon?’ has a high specificity in children, the sensitivity of taking a history is only around 50% in children with positive latex challenges [12, 19, 22]. …”

HETA 99-0035-2757, LDS Hospital/Intermountain Health Care, Salt Lake City, Utah.

“…The prevalence of latex allergy in the general population is believed to be less than 1%. 35,36,37 People who have a genetic predisposition for allergy ("atopics") may have a 3-7% prevalence of latex allergy. 34,35 Studies in health care workers have shown latex allergy prevalence rates of 2-16.9%.…”