Alarming Prevalence of Community-Associated MRSA Detected Among Emergency Department Patients

WASHINGTON, D.C. -- Methicillin-resistant Staphylococcus aureus (MRSA) was found in an alarming number of patients who sought treatment for skin and soft tissue infections at a Northern California hospital emergency department, according to a study to be published online by Annals of Emergency Medicine. A related editorial questions the ability of the nations emergency departments to isolate these patients given widespread overcrowding problems.

The bacterium Staphylococcus aureus, or staph, is a common cause of skin and soft tissue infections, and strains resistant to treatment with methicillin and related antibiotics have existed for decades. While MRSA was once thought to be acquired mostly in health care facilities, today cases of MRSA acquired in the community are increasingly being reported. The good news is that compared to hospital-associated MRSA strains, community-associated MRSA (CA-MRSA) is susceptible to a broader array of antibiotics; the bad news is that CA-MRSA may be more virulent than typical hospital strains.

In this study, researchers found more than half (51.3 percent) of skin and soft tissue infections among emergency department patients were caused by MRSA and 76 percent of MRSA infections fit a strict clinical definition of community-associated. When MRSA samples were genetically tested, 98.8 percent were found to carry the genetic fingerprint of community acquisition, and 87.1 belonged to a single genetically identical group, suggesting that MRSA is spreading rapidly within the Oakland and San Francisco areas, where the study took place.

Despite CA-MRSA spreading throughout these communities, researchers found few demographic similarities among the infected patients. What they did find is that they were more likely to be white, and their infections were more likely to take the form of a furuncle.

Despite the well-documented emergence of CA-MRSA in the U.S., evidence of its prevalence among otherwise healthy emergency patients has not been explored, said lead author Bradley W. Frazee, MD, with the Department of Emergency Medicine at Alameda County Medical Center in Oakland and the Department of Medicine at the University of California, San Francisco. Our research is important in making public health officials and emergency physicians, who are on the front lines treating MRSA-related diseases, aware of CA-MRSAs prevalence. We now need to consider what measures are needed to reduce its spread in the community as well as among emergency patients.

Once MRSA infection is identified, patients typically are placed into isolation rooms by health care workers who are wearing gowns and gloves, according to the lead author of a related editorial, Gregory J. Moran, MD, with the Department of Emergency Medicine and Division of Infectious Diseases at the Olive View-UCLA Medical Center in Sylmar, Calif. However, in many institutions this now appears to be somewhat of a farce considering they lack the capacity to do this because the emergency departments are overcrowded by patients who are awaiting hospital admission, he said.

What is abundantly clear is that we need more research on this new phenomenon of CA-MRSA, said Moran. In addition, infection control practices to reduce MRSA transmission as well as other infectious diseases in overcrowded emergency departments need to be evaluated.

Source: American College of Emergency Physicians