To assess the prevalence of bacterial contamination of spacer devices used by asthmatic children.

A cross-sectional study at a tertiary centre in India included asthmatic children aged 5 to 17 years who were using metered-dose inhaler (MDI) with a spacer for at least three months. A sterile cotton swab pre-moistened in sterile brain heart infusion (BHI) broth, rotated around the inner surface of the spacers, was smeared on blood agar and MacConkey agar plates. Plates were incubated for bacterial growth and examined for colony growth.

A total of 180 children were enrolled with a median (Q1, Q3) age of 12 (9, 14) years. Out of 180 spacer devices, 72 (40%) had pathogenic isolates and 108 (60%) had non-pathogenic isolates; Pseudomonas aeruginosa (28%) was the most common pathogenic bacteria. Only 17.8% (n = 32) were washing the spacer using soap and water; 84.4% (n = 152) patients used the air-dry method, and 15.6% (n = 28) dried the spacer using a cloth. There was no significant association between bacterial contamination and/or washing technique (P = 0.079). However, drying of spacer with a cloth was significantly associated with the growth of pathogenic bacteria as compared to air drying (P < 0.001). Bacterial contamination did not impact the asthma control (P = 0.491).

A high prevalence of bacterial contamination of spacer devices was noted in asthmatic children, although it was not associated with asthma control.