ABSTRACT
An outbreak of Multi-Drug Resistance Pseudomonas aeruginosa (MDRP) infections occurred in intensive care unit (ICU) and emergency room (ER) between June and August 2007. Five patients who isolated MDRP in the outbreak of 2007 were all used bronchoscopes, thus, we suspected contamination of the bronchoscopes as the cause of outbreak. Although we did not detect MDRP from any bronchoscopes, the outbreak finally ended after all the bronchoscopes had been disinfected appropriately with the reexamination of washing process in 2008 and 2009. We retrospectively reviewed eleven patients who isolated MDRP in 2006 and 2007, and the fact was revealed that bronchoscopes were used in most patients in ICU and ER. Bronchoscopes were significantly used during 2006-2007 period, compared with 2008-2009 period in ICU and ER, and the case-control analysis among all Pseudomonas aeruginosa isolated patients identified that bronchoscopes [risk ratio (RR) 8.25, 95% confidence interval (CI) 1.328-51.26] was one of the most important risk factors for MDRP isolation. Duration from admission to MDRP isolation was significant longer in MDRP-isolated cases (19.82±12.77 d), compared with in non MDRP-isolated controls (11.76±11.69 d: p=0.0453). Our epidemiological analysis suggested the significant risk factors for an MDRP outbreak, and could contribute the estimation of the focus and prevention of future outbreaks.
Subject(s)
Bronchoscopes/microbiology , Cross Infection/etiology , Disease Outbreaks , Drug Resistance, Multiple, Bacterial , Equipment Contamination , Pseudomonas Infections/etiology , Pseudomonas aeruginosa , Adult , Bronchoscopy , Case-Control Studies , Cross Infection/epidemiology , Cross Infection/microbiology , Disinfection , Emergency Service, Hospital , Female , Humans , Intensive Care Units , Male , Middle Aged , Pseudomonas Infections/epidemiology , Pseudomonas Infections/microbiology , Retrospective Studies , Risk FactorsABSTRACT
Multidrug-resistant Pseudomonas aeruginosa (MDRP) is a major problem among hospital-acquired infections. We had a one-month outbreak of this strain at a university hospital in Osaka, Japan, from May to June 2004. To determine the cause of the outbreak, we collected and analyzed epidemiological information about the patients from whom MDRP was isolated, and performed microbiological investigations. MDRP was detected in respiratory specimens from eight patients in the intensive care unit. One of these patients developed severe lethal pneumonia accompanied by septicemia, and two contracted less severe non-lethal pneumonia. All the MDRP patients had been monitored with a contaminated transesophageal echocardiography (TOE) probe during their cardiac surgery. The TOE probe proved to have a defect 5 mm in diameter at the surface near the transducer, and the MDRP strain was traced to this defect. Pulsed-field gel electrophoresis showed that the strain isolated from the patients and from the TOE probe were genetically indistinguishable. After use of the damaged TOE probe was terminated, MDRP was not isolated from any patients who underwent cardiac surgery in the subsequent 8 years. In conclusion, TOE is routinely used during cardiac surgery and has been shown to have a significant clinical effect. Prevention of similar post-operative pneumonia outbreaks will require thorough infection control of TOE probes used for monitoring during cardiovascular surgery.
