Recurrent wheezing after bronchiolitis caused by respiratory syncytial virus in children younger than 3 years: A 1-year follow-up study

We analysis the frequency and risk factors of wheezing in infants. We chose children with initial wheezing before 3 years of age who were hospitalized for medical treatment. Wheezing frequency was determined by follow-up at 1 week, 1 month, 3 months, 6 months, and 1 year. Information such as birth status, age, sex, preterm, mode of delivery, birth order, eczema history, personal allergy history, family allergy history, passive smoking, and place of residence (urban/rural) was collected. Total serum IgE level, serum allergen testing, routine blood tests, C-reactive protein level, procalcitonin level, respiratory pathogens tests, sputum culture, chest radiography or computed tomography were performed in all patients. The correlation between each factor and wheezing recurrence was evaluated. A total of 259 children were included in the study. They were divided into single recurrence, multiple recurrences, and no recurrence groups. The recurrence rate of wheezing was 56.8% (30.5% had a single recurrence and 26.3% had 2 or more recurrences). The percentage of children with a personal allergy history in the multiple recurrences group was significantly higher than in the single recurrence and no recurrence groups ( P = 0.031 and 0.008, respectively). The age of the children in the multiple recurrences group was significantly lower than that in the single recurrence group ( P < 0.001). Clinical severity scores were higher in the multiple recurrences group than in the single recurrence and no recurrence groups ( P = 0.002 and <0.001, respectively). Most children did not experience multiple recurrent wheezing. Children with young age, serious condition, and allergic constitution were prone to recurrent wheezing.