Outbreak of joint and soft-tissue infections associated with injections from a multiple-dose medication vial

An outbreak of Staphylococcus aureus joint and soft-tissue infections occurred after therapeutic injections in an outpatient setting. A physician performed intra-articular or soft-tissue injections on 17 patients in August 2001, and 5 (29%) were subsequently hospitalized for infections at the site. S. aureus was isolated from 4 patients, and all 4 isolates were indistinguishable by pulsed-field gel electrophoresis. Of 10 patients injected with lidocaine and triamcinolone, 5 (50%) developed infections, compared with 0 of 7 patients injected with triamcinolone only (P = .04). A multiple-dose vial (MDV) of lidocaine was likely contaminated with S. aureus. A possible contributing factor was refrigeration after the use of MDVs of lidocaine; the manufacturer recommends storage at room temperature. An in vitro study of S. aureus in MDVs of lidocaine revealed prolonged survival at refrigerator temperatures. This outbreak highlights the importance of strict attention to aseptic procedures and carefully following manufacturers' instructions when using MDVs.