Immediate, Aggressive Treatment Necessary to Fight MRSA

DES PLAINES, Ill. -- Drug-resistant hospital-acquired infections often are treated initially with ineffective antibiotics, which increases the risk of death, according to an article in the August issue of Critical Care Medicine, the journal of the Society of Critical Care Medicine.

The researchers conducted a three-year retrospective study of 549 Barnes-JewishHospital patients with MRSA sterile-site infection to determine the rate of appropriate initial antimicrobial administration and to evaluate the influence of this treatment on outcome. They found that nearly one in three MRSA-infected patients initially received inappropriate treatment for MRSA infection, nearly doubling their risk of death.

“Physicians should deliver early appropriate antibiotic therapy,” says senior author Marin H. Kollef, MD, professor of medicine at Washington University School of Medicine in St. Louis.  “For methicillin-resistant Staphylococcus aureus (MRSA) that means treating acutely ill hospitalized patients with antibiotics that are active against MRSA instead of less effective antibiotics.  The occurrence of MRSA has skyrocketed in the last five to 10 years and is now the most common hospital pathogen.”

Hospital-acquired MRSA infections have serious consequences, including increases in the risk of death and in healthcare costs. Patients in intensive care units are particularly vulnerable. Hospital mortality associated with MRSA sterile-site infections is reported to be greater than 20 percent.

Lead author Garrett E. Schramm, PharmD, says that it is crucial for physicians to aggressively identify and treat patients at risk for sterile-site MRSA infections and for physicians to be aware of local susceptibilities for both hospital and community-acquired MRSA isolates. 

“In our ICUs, we automatically treat for MRSA along with other bacteria when we have a patient with hospital-acquired infection,” says Kollef. “Obviously, not everyone will have MRSA infection, but it is so common and the consequences of not treating it upfront are so high that we treat for MRSA before its presence is confirmed.”

Kollef says there are no drawbacks to including MRSA treatment in initial therapy, as long as clinicians monitor the patient. If the culture results show no evidence of MRSA infection, then MRSA-related antibiotics can be stopped. In most patients, this is done within 48 hours.

Schramm says that there are a variety of antibiotics that can treat MRSA infections.  Many are given intravenously and are appropriate for hospital use, while some, including sulfamethoxazole-trimethoprim, can be administered orally and may be used to treat community-acquired MRSA infections. Schramm is a clinical pharmacist at Mayo Clinic in Rochester, Minn., and a former critical care specialty resident at Barnes-JewishHospital in St. Louis.

“We have the antibiotics, and now we should develop optimal treatment algorithms,” concludes Kollef. “This will provide early appropriate therapy, while minimizing emergence of further resistance in MRSA and other bacteria.”

In an accompanying editorial, “Making the Wrong Choice: Consequences for Patients with Infections Due to Methicillin-Resistant Staphylococcus aureus,” also in the August issue of Critical Care Medicine, lead author Andrew F. Shorr, MD, MPH, from Washington Hospital Center in Washington, D.C., expands on the research of Schramm and his coauthors.  “As newer tools for rapid diagnostics and organism identification become commercially available we will need to update our approach to antimicrobial prescribing generally and for MRSA specifically,” concludes Shorr. “However, in the absence of some marker that allows for accurate and reliable determination of resistant isolates, few options exist.  If clinicians fail to acknowledge and adapt to the current situation surrounding infection management, patients will continue to be unnecessarily and inexcusably exposed to the risk of inadequate therapy.  This simply becomes a question of ownership.  If we do not act, who will?”

“MRSA infection is becoming more common while remaining equally deadly,” says Joseph E. Parrillo, MD, editor-in-chief of Critical Care Medicine. “MRSA is a changing organism and a changing type of infection.  We need more clinical research in this area to optimize treatment and to better understand the epidemiology of MRSA infection.”

Source: Society of Critical Care Medicine