ATOPY, BRONCHIAL HYPERRESPONSIVENESS, AND PEAK FLOW VARIABILITY IN CHILDREN WITH MILD OCCASIONAL WHEEZING

Background - Children who suffer from recurrent wheezy episodes are of ten promptly classified as asthmatic. The aim of this study was to eva luate a population of mild wheezy children with repeatedly normal spir ometric tests at rest for atopy, bronchial hyperresponsiveness, and pe ak expiratory flow variability. Methods - Thirty nine children aged 6- 16 years with 1-12 wheezy attacks during the previous year were recrui ted from a community paediatric primary health care clinic serving an urban Israeli population. The conditions for inclusion were a physicia n-diagnosed wheeze on auscultation and normal spirometric tests at res t on at least three occasions. Evaluation included skin prick tests fo r atopy and a physician-completed questionnaire. In addition, two test s of bronchial hyperresponsiveness (BHR) were performed - namely, exer cise-induced bronchospasm and inhaled methacholine hyperresponsiveness - as well as diurnal variability of peak expiratory flow (PV). Result s - One or more tests of BHR/PV were positive in 27 (69%) but repeated ly negative in 12 (31%). In terms of frequency of wheezing attacks, at opy, and questionnaire responses, there were no differences between BH R/PV and non-BHR/PV children, with the exception of a history of chest radiography proven pneumonia (only noted in the BHR/PV group). Overal l, evidence of atopy (mainly indoor allergens) was noted in 21 (56%) o f those tested and parental smoking in 29 (74%) of households. Thirty- two (82%) of the children complained of an exercise-related wheeze, ye t exercise-induced bronchospasm was only demonstrated in nine (23%). C onclusions - This selected group of wheezy children appears to be inte rmediate between a normal and clearly asthmatic population and, despit e the recurrent wheezy attacks, some should probably not be classified as asthmatic by conventional criteria. Important aetiological factors in the symptomatology of these children may include parental smoking and atopy as well as other elements such as viral infections.