Bronquiolitis y obstrucción bronquial recurrente: ¿es la eosinofilia un factor de riesgo?

Abstract

Objectives To investigate the final outcome of infants presenting anepisode of bronchiolitis and to analyze the risk factors forthe development of persistent wheezing, with special attentionpaid to the presence of eosinophilia during theacute episode. Patients and methods We studied all the children aged less than 2 years whorequired hospitalization for bronchiolitis between 1990and 1993. Eosinophil values during the acute phase werecollected. Clinical evolution and outcome were classifiedin three groups: short-term persistent wheezing (if resolvedbefore the child reached the age of 5 years),long-term persistent wheezing (if the child remainedsymptomatic after the age of 5 years) and no wheezing.Other risk factors for asthma such as familial history, passivesmoking and respiratory syncytial virus isolationwere also studied. Results We analyzed 170 patients (100 boys and 70 girls) aged7.15 6 0.78 years who suffered an episode of acute bronchiolitisat the age of 5.4 6 4.2 months. One hundred thirteenpatients (66.5 %) developed short-term persistentwheezing and 60 (35.3 %) developed long-term persistent wheezing. Fifty-six patients presented no wheezing. Thenumber of patients with eosinophils>1% was significantlydifferent in the three groups of patients (p 5 0.029).A Eosinophil values of>1% was associated with shorttermpersistent wheezing (p 5 0.013). Mean eosinophilvalues were higher in patients who developed wheezing atsome time during evolution (p 5 0.028). A familial historyof asthma was associated with the development oflong-term persistent wheezing (p 5 0.033). Conclusions In the population studied, eosinophil values of>1%during an episode of acute bronchiolitis in infancy was associatedwith a higher risk of developing persistent wheezingin the first 5 years of life. A familial history of asthmawas associated with a higher risk of developing long-termpersistent wheezing.