The prevalence of latex sensitisation and allergy in Danish atopic children - Evaluation of diagnostic methods

Background: All over the world natural rubber allergy is reported to be responsible for a wide spectrum of allergic symptoms ranging from mild rhinitis to severe anaphylaxis. Aim: To estimate the prevalence and the clinical significance of latex sensitisation in atopic children seen in a university paediatric outpatient clinic. Materials and methods: During 1997-1998, a total of one hundred atopic children (4-14 years old, 64 boys and 36 girls) were consecutively screened for latex sensitisation by skin prick tests (SPTs) with standard inhalant allergens (ALK) and latex (Stallergenes SA), measurement of specific IgE (CAP System, Pharmacia, and Magic Lite, ALK) and total IgE. A clinical history, with attention to surgical history, latex exposure and presence of symptoms possibly due to latex or food allergy was obtained. Results: Five children (5%) had positive SPT to latex. Four (4%) had positive specific IgE to latex but had a negative SPT to latex, Only one patient (1%), who had spina bifida, had a positive SPT together with symptoms which could be related to latex allergy. This patient also had RAST class 4 to latex both with CAP System and Magic Lite. A history of previous surgery was found in only one of the children with positive latex SPT. Latex CAP System vas positive in two of the five latex SPT positive patients, and latex Magic Lite in one of the five. In one patient without any symptoms of latex allergy, both SPT and in vitro tests were positive. Another child without symptoms, and with negative SPT, also had positive in vitro results. Conclusion: We found that the prevalence of sensitisation to latex as 9% in atopic children, but the prevalence of manifest type 1 latex allergy was only 1%. Latex allergy in atopic children seems to be a small problem in Denmark. How to evaluate the significance of positive in vitro tests and positive latex SPT in patients without symptoms to latex. remains an open question.