Detection and molecular characterization of a gentamicin-susceptible, methicillin-resistant Staphylococcus aureus (MRSA) clone in Rio de Janeiro that resembles the New York/Japanese clone

Genotyping of methicillin-resistant Staphylococcus aureus isolates obtained in the Northeast region of Brazil

“…Previous studies have also shown that community-acquired MRSA, which are generally more susceptible to antibiotics than HA-MRSA isolates, have also emerged as healthcare-associated pathogens (2,17). The detection of USA800 (pediatric clone) in Natal corroborates other studies indicating that this clone type is an important emergent nosocomial agent in Brazil (9,10,12). USA800 isolates have been recently detected in hospitals located in Rio de Janeiro and Recife (10).…”

“…The strains belonging to BEC and its subtypes were resistant to most of the antimicrobials tested, except vancomycin and one or two other drugs, and showed homogeneous resistance to methicillin (since they all grew confluently on 25 µg/mL methicillin plates). The BEC strain is endemic in Brazilian hospitals, and its predominance among HA-MRSA has been reported since 1992, when it was first described in the country (5,6,12). This clone has also been isolated in other South American countries, in Europe and in Asia (1,3), demonstrating a superior ability for worldwide dissemination.…”

“…The disk-diffusion test was performed according to the recommendations of the Clinical and Laboratory Standards Institute (11). Methicillin agar screening (25Met) was carried out using trypticase soy agar containing 25 µg/mL methicillin (Sigma, USA) and a heavy bacterial inoculum (10 9 -10 10 cfu) as described previously (12). The methicillin-susceptible strain of S. aureus ATCC 29213 and the MRSA isolate BMB9393 were used to control the susceptibility tests.…”

“…It is interesting to note that pattern A 1 was observed in only 24.2% of the BEC isolates. BEC isolates have spread throughout Brazil for more than a decade and previous studies have shown that pattern A 1 accounted for 70-80% of the BEC subtypes (5,12,15). Thus, it seems likely that small genomic changes may have occurred during these years resulting in BEC variants also well-adapted to cause severe hospital infections.…”

Controlling a Multicenter Outbreak Involving the New York/Japan Methicillin-ResistantStaphylococcus aureusClone

“…Since 2000, the New York/Japan clone has been reported in several US states, [7][8][9] Canada, 10 Brazil, 11 Mexico, 12 China, 13 and Korea. 14,15 Although infrequently reported in Europe, the New York/Japan clone has recently been described as a major epidemic MRSA (EMRSA) clone in Hungary.…”