Hospital acquired outbreak of methicillin-resistant Staphylococcus aureus infection initiated by a health care worker.

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) has become an increasingly important pathogen leading to hospital acquired infections. AIM: This study was done to confirm an outbreak of MRSA suspected at Charles Nicolle Hospital. METHODS: From 26 April to 11 June 2002, six patients hospitalized in the dermatologic ward at Charles Nicolle hospital of Tunisia have developed infections caused by MRSA. An investigation of the outbreak has been detected a nasal carriage nurse. This carrier received topical mupirocin treatment to decolonize the anterior nares and the outbreak was stopped without further incident. RESULTS: Typing of the MRSA strains by pulsed field gel electrophoresis demonstrated the same pulsotype shared by all isolates showing that MRSA isolates belonged to a single clonal type responsible of outbreak. Colonized nurse was the source of MRSA dissemination. CONCLUSION: This report illustrates the risk of nosocomial outbreak linked to cares delivered by the staff personnel. More sensibilisation and the respect of strict hygienic measures should be emphasized.

Clonal spread of carbapenem resistant Pseudomonas aeruginosa in an university hospital.

AIM: We examined 14 Pseudomonas aeruginosa clinical isolates collected in 2000 from patients hospitalised in different wards at Charle Nicolle hospital from Tunisia. METHODS: Analysis includes serotyping, antimicrobial susceptibility profile, beta-lactamase detection, randomly amplified polymorphic DNA and pulsed field gel electrophoresis. All Pseudomonas aeruginosa strains belonged to serotype O12 and they demonstrated a high level of resistance to all antibiotioc tested. RESULTS: Beta-lactamase detection revealed that 9 of these strains had ceftazidime activity restored by cloxacillin and none of the 14 strains were metallo-beta-lactamase producing. Randomly amplified polymorphic DNA analysis and pulsed field gel electrophoresis were able to discriminate isolates and gave concordant results which showed epidemiologically related strains. CONCLUSION: These results confirm a clonal spread of multiresistant Pseudomonas aeruginosa O12 throughout the hospital.