Outbreak of Multiantimicrobial-Resistant Acinetobacter baumannii Related to Pulsatile Lavage

Abstract

ISSUE: We investigated an outbreak of multiantimicrobial-resistant Acinetobacter baumannii (MDR-AB) in a 1000-bed hospital. A. baumannii survives on surfaces for extended time periods and colonizes or infects the respiratory tract and wounds. PROJECT: In October 2003, 12 patients had MDR-AB cultured from wounds. Cases were patients with cultures (CX) growing MDR-AB. MDR-AB were resistant to all antibiotics except colistin. Strict contact isolation was implemented. Sign-in was required for entry into patient pt rooms to track potential exposures. Record review revealed that all case patients underwent wound care with Pulsatile Lavage (PL), which is a pressurized wound flush device. The procedure was observed, environmental CX were collected in the treatment area and all patients who underwent PL were identified. CX of the PL environment grew MDR-AB. The treatment area was closed and thoroughly cleaned. Staff was instructed on proper infection control. Surveillance CX of all patients treated with PL was obtained from the time the index case was identified. Pulsed-field gel electrophoresis revealed that 6 patients who received PL had identical strains, which were also identical to environmental CX. We hypothesized the organism was aerosolized during PL therapy based on 1) environmental contamination matching the outbreak strain, and 2) infected patients. RESULTS: The outbreak resolved after all CX-positive patients were identified and aggressive infection control measures were instituted. No new cases were identified after October 2003. LESSONS LEARNED: MDR-AB can be transmitted by aerosolization during PL. The FDA and CDC have worked to change the infection control procedures in the product labeling on the PL device.