Spread of Clones of Multidrug-Resistant, Coagulase-Negative Staphylococci Within a University Hospital

• Published in: Infection Control & Hospital Epidemiology
• Main Authors: Monsen, Tor, Karlsson, Carina, Wiström, Johan
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press (CUP) 2005
• Subjects: Northern Sweden
• Online Access: http://dx.doi.org/10.1086/502490; https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0899823X00197429

Abstract Objective: To detect putative clonal dissemination of multidrug-resistant, coagulase-negative staphylococci (CNS) in a university hospital in northern Sweden. Methods: All consecutive routine clinical samples from our hospital were screened during two periods (November and December 2001 and September and October 2002) for the presence of multidrug-resistant (defined as resistant to oxacillin, clindamycin, co-trimoxazole, gentamicin, and fusidic acid, but susceptible to vancomycin) isolates of CNS. Genetic similarity between isolates was analyzed using pulsed-field gel electrophoresis (PFGE) and a computer program. Results: Seventy multidrug-resistant isolates from 62 patients were identified, 28 during the 2001 period and 42 during the 2002 period. All isolates except one, which was Staphylococcus haemolyticus , were identified as S. epidermidis . Multidrug-resistant CNS were isolated in samples obtained from 24 different wards. Two subgroups (group A and group B) of S. epidermidis that differed by approximately 40% in PFGE band similarity were identified. Group A consisted of 44 isolates with a PFGE band similarity of greater than 70% that included 6 subgroups consisting of 3 to 16 isolates that expressed a 100% similarity. These isolates were identified during both sampling periods in cultures performed in 18 different wards. A clonal origin could not be excluded for some of the remaining 26 isolates belonging to group B, but none had identical PFGE patterns, suggesting a more diverse origin. Conclusion: The results of this study suggest clonal spread of multidrug-resistant CNS within our hospital and that some clones are endemic in the hospital environment.