Severe methicillin-susceptible Staphylococcus aureus infections associated with epidural injections at an outpatient pain clinic.

BACKGROUND: Recent outbreaks in ambulatory care settings have highlighted infection control breaches as risk factors for disease transmission. In May 2009, 3 patients were hospitalized with severe methicillin-susceptible Staphylococcus aureus (MSSA) infections after receiving epidural injections at a West Virginia outpatient pain clinic. METHODS: We conducted a retrospective cohort study evaluating clinic patients who received injections during a 3-week period. A case was defined as laboratory-confirmed infection or clinical evidence of infection ≤ 14 days after a patient received an injection. Infection control procedures were assessed. MSSA isolates from patient infections and clinic staff nasal swabs were genotyped by using pulsed-field gel electrophoresis. RESULTS: Eight (7%) of 110 cohort patients met the case definition; 6 (75%) cases were laboratory confirmed. Eight (12%) of 69 patients who received epidural injections were case patients compared with none of the other 41 patients (P = .02). During procedures, staff use of face masks and preparation of patient skin were suboptimal; epidural injection syringes were reused to access shared medication vials. MSSA isolates from 2 patients and 1 staff member were indistinguishable by pulsed-field gel electrophoresis. CONCLUSION: Infection control breaches likely facilitated MSSA transmission to patients receiving epidural injections. Adhering to correct infection control practices in ambulatory care settings is critical to prevent disease transmission.