Nosocomial respiratory infection due to an imipenem-resistant Pseudomonas aeruginosa O: 12 strain in a Tunis's neonatal intensive care unit

OBJECTIVE: Investigation of an outbreak caused by an imipenem-resistant Pseudomonas aeruginosa strain and research of its hospital reservoir. PATIENTS AND METHODS: Nine strains isolated from protected tracheal specimens during 14 weeks (October 2004 to January 2005) from 8 infants, and one strain from vacuum interrupter were studied. Epidemiological study was investigated by determination of antibiotics susceptibility, serotyping and Pulsed-field gel electrophoresis (PFGE). RESULTS: Strains were of O:12 serotype, they have the same antibiotype characterised by imipenem resistance. Strains were indistinguishable or closely related as determined by PFGE. The common source of P. aeruginosa O:12 strains was not determined, however eradication of the epidemic strain was obtained by amelioration of hygiene conditions and the change of disinfectors. CONCLUSION: Outbreak of respiratory infections due to an imipenem-resistant P. aeruginosa O:12. The common source of the epidemic strain was not determined.