A Novel Methicillin-Resistance Cassette in Community-Acquired Methicillin-Resistant Staphylococcus aureus Isolates of Diverse Genetic Backgrounds.
Daum, Robert S. 1; Ito, Teruyo 2; Hiramatsu, Keiichi 2; Hussain, Farid 1; Mongkolrattanothai, Kanokporn 1; Jamklang, Mantana 2; Boyle-Vavra, Susan 1
[Miscellaneous]
Journal of Infectious Diseases.
186(9):1344-1347, November 1, 2002.
(Format: HTML, PDF)
: Until recently, it has been unclear whether community-acquired (CA) methicillin-resistant Staphylococcus aureus (MRSA) isolates represent the spread of hospital MRSA isolates into the community. In 2 CA-MRSA isolates, a novel genetic element, designated staphylococcal cassette chromosome mec (SCCmec) type IV, was found; it differs from SCCmec types I-III in its small size and absence of non-[beta]-lactam genetic-resistance determinants. To study the prevalence of type IV SCCmec polymerase chain reaction characterization of SCCmec was performed on DNA from 12 CA-MRSA isolates. The 12 CA-MRSA isolates were from diverse genetic backgrounds, as evidenced by their stratification into 5 pulsed-field gel electrophoresis types, 4 coagulase types, and 2 ribotypes. Eleven of the 12 isolates contained the novel SCCmec type IV element. Ten were resistant only to [beta]-lactam antibiotics. SCCmec type IV is present on the genome of CA-MRSA isolates. Its relatively small size and presence in isolates of diverse genetic backgrounds suggest that it may spread among S. aureus isolates.
(C) Copyright Oxford University Press 2002.