MRSA presents both clinical and infection control challenges. Because of the increasing incidence of MRSA strains, empiric treatment for serious staph infections is usually vancomycin in the hospital setting. Although PNA-FISH can identify Staphylococcus aureus more rapidly, it cannot yet differentiate MRSA from methicillin-susceptible S. aureus (MSSA) strains. Early differentiation of MRSA from non-MRSA strains could allow for adjustment from broad-spectrum antimicrobial therapy and reduce the risk of developing resistance.
Hospital-acquired infections have garnered increasing attention from many quarters; MRSA is one of several drug-resistant organisms of concern. Many institutions have implemented active surveillance culture (ASC) protocols to identify carriers of MRSA, both upon admission and throughout the hospital stay. Identified carriers are placed under precaution protocols to minimize the risk of transmission to other patients during the hospital stay. MRSA status is also important for patients being discharged to another facility, such as long-term care or rehabilitation centers.
Identifying carriers sooner rather than later can reduce the risk of transmission by earlier implementation of precaution protocols and reduce delays in discharge (and length of hospital stay) in situations where carrier status is needed before discharge. Depending on the culture medium employed, PCR methodologies offer the prospect of providing screening results 24 to 40 hours sooner than culture methodologies.
