MRSA: What goes around comes around

Community strain strikes hospital

Saiman L, O’Keefe M, Graham III PL. Hospital transmission of community-acquired methicillin-resistant Staphylococcus aureus among postpartum women. Clin Infect Dis 2003; 37:1,313-1,319.

As community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) increases, we now find that the bug can cause further problems by joining its nosocomial cousins in the hospital The fear used to be that MRSA would leave the hospital, but it appears community strains can just as likely come in.

The authors described eight postpartum women who developed skin and soft-tissue infections caused by MRSA at a mean time of 23 days (range, 473 days) after delivery. Infections included four cases of mastitis (three of which progressed to breast abscess), a postoperative wound infection, cellulitis, and pustulosis. The outbreak strains were compared with the prototype CA-MRSA strain MW2 and found to be indistinguishable by pulsed-field gel electrophoresis. The route of transmission was not discovered: The results of surveillance cultures of samples obtained from employees of the hospital, the hospital environment, and newborns were negative for the outbreak strain. "We report that MW2, which was previously limited to the Midwestern United States, has spread to the northeastern United States and has become a health care associated pathogen," the authors concluded.