Inhaled corticosteroids increase the risk of oropharyngeal colonization by Streptococcus pneumoniae in children with asthma

Background and objective: Recent studies have raised concerns about the link between use of inhaled corticosteroids (ICS) and risk of pneumonia in patients with chronic obstructive pulmonary disease. This cross-sectional study aimed to investigate the association between ICS and oropharyngeal colonization by Streptococcus pneumoniae (S. pneumoniae) among children (up to 18 years old) with asthma. Methods: Two age-matched groups of patients were consecutively recruited: (i) exposed group: children who had persistent asthma and were being treated with daily ICS for at least 30 days and (ii) non-exposed group: children who had asthma and were not being treated with ICS at study entry. Oropharyngeal specimens from the tonsillar area and posterior pharyngeal wall were collected. S. pneumoniae was identified according to National Committee for Clinical Laboratory Standards recommendations. Results: A total of 200 consecutive patients were recruited and 192 (96 in each group) were included in the analysis. In the exposed group, the mean daily dose of ICS was 400 mg of beclomethasone or equivalent and the mean duration of treatment was 8.6 months. The prevalence of oropharyngeal colonization by S. pneumoniae was higher in the exposed group compared with the non-exposed group (27.1% vs 8.3%, P = 0.001). After adjusting for potential confounders, use of ICS was an independent risk factor for oropharyngeal carriage of S. pneumoniae, with an adjusted prevalence ratio of 3.75 (95% confidence interval: 1.72-8.18, P = 0.001). Conclusions: Regular use of ICS is associated with an increased risk of having oropharyngeal colonization by S. pneumoniae in children with asthma.