Risks of allergy vial contamination: Comparison of mixing in-office versus under ventilation hood

Abstract

Objective Compare the risk of bacterial contamination of allergy immunotherapy vials prepared in-office versus those mixed under a ventilation hood. Study Design Prospective single-blinded study. Setting Tertiary otolaryngology outpatient clinic. Results Five hundred thirty-seven vials were prepared and cultured for aerobes and anaerobes over an 11-month period. Three hundred twenty vials were arbitrarily assigned to in-office preparation and 217 to under-hood preparation. A total of two positive cultures occurred in vials prepared in-office and one from under-hood preparation. Follow-up cultures of these three vials were all negative. No patients receiving injections had signs or symptoms of skin or systemic infections from the injections. Conclusion Our results suggest that the risk of bacterial contamination in immunotherapy vials in both groups is rare.