Are bulb syringe irrigators a potential source of bacterial contamination in chronic rhinosinusitis?

Background: The purpose of this study was to determine if bulb syringe irrigators are a potential source for bacterial contamination in patients with chronic rhinosinusitis. Methods: Standard 3-oz bulb syringe irrigators (n = 24) were each flushed with the following solutions twice daily: A (n = 8), sterile isotonic saline; B (it = 8), prepared hypertonic saline (3 tsp table salt/L of sterile water); and C (n = 8), prepared baking soda/saline (1 tsp table salt + 1 tsp baking soda/L of commercial sterile water). Syringes were stored on a residential bathroom counter, and two from each group were harvested for culture weekly for 4 weeks. Results: There was no growth from syringes irrigated with any of the three solutions after the first 7 days of irrigation. After the entire 4-week study period, potential pathogens were recovered from 618 (75%) bulbs from group A, 018 bulbs from group B, and 118 bulbs (12.5%) from group C. All positive cultures revealed growth by 1-2 days postinoculation (p = 0.002). The organism recovered from syringes in group A was Pseudomonas fluorescens in all six specimens. The one positive culture in group C represented a single colony of Gram-positive cocci. Conclusion: Under realistic conditions, bulb syringes are susceptible to contamination with potential bacterial pathogens, particularly when using unbuffered isotonic saline.