Croup, Croup, recurrent croup, allergy and airway hyperreactivity

Abstract

Twenty one children with recurrent croup (RC) and eleven with acute laryngotracheobronchitis (LTB) were studied three to five years after last croup episode. Their mean age was 8.5 ± 1.9 years. They were evaluated with a questionnaire, physical examination, allergy skin tests, pulmonary function tests, and histamine inhalation challenge. Among the children with RC there was a clear male predominance and earlier onset of the disease could be observed. There was a significant association between RC and a positive family and personal history of allergy, as well as croup among brothers. Seven children from RC group developed atopic asthma (33.3%), whereas only one child from LTB group developed asthma (9.0%). Only one atopic asthmatic child showed obstruction of the lower airway. Children with RC showed lower expiratory flow rates than those with LTB. An increase of bronchial reactivity (PC20FEV1 <16 mg/ml) was observed in 10 children (37.5%), with a similar prevalence of airway hyperreactivity in both groups CR and LTB. It is suggested that RC and bronchial asthma share a few characteristics and also that RC may respond to antiasthmatic treatments.