Program to Reduce MRSA Infections

A new system-wide admission-screening program across three hospitals to detect methicillin-resistant Staphylococcus aureus (MRSA) is being undertaken as a major patient-safety initiative.

The program was developed by Evanston Northwestern Healthcare (ENH, Illinois, USA) in response to the growing prevalence of MRSA infections in hospitals. The U.S. Centers for Disease Control and Prevention (Atlanta, GA, USA) estimates that in 1999 there were 126,000 people in U.S. hospitals with MRSA infections, and the problem has grown much worse since then.

The program is using a combination of the electronic medical record and same-day molecular testing to screen patients on admission and determine if they are infected with MRSA or are colonized with the bacteria but not yet infected. Doctors can immediately identify and treat patients because the electronic medical record contains an admission sheet for each patient that prompts the admitting team to order and collect a nasal swab before a healthcare provider moves to the next computer screen.

"This electronic ‘red flag' alert ensures compliance and allows us to document cases in which a patient may refuse the test,” explained Lance Peterson, M.D., FASCP, epidemiologist and professor of pathology and medicine at Northwestern University's Feinberg School of Medicine.

Each patient's nasal sample is then tested, using real-time DNA analysis developed by GeneOhm Sciences, Inc. (San Diego, CA, USA). The test detects the microorganism at the molecular level and compresses the time frame to identify MRSA from the current two-to-four days, using traditional culture methods, to less than two hours. Once diagnosed, patients are treated with a nasal antibiotic ointment for five days.

For the past two years, ENH has screened for S aureus in the highest patient-risk areas, including the infant special care unit (ISCU), and has also conducted a targeted pilot program with a rapid molecular method to screen selective preoperative patients undergoing knee surgery. As a result, the rate of post-surgical S aureus infection was reduced nearly four-fold. However, in September 2004, a study in the hospital revealed that 8% of its patients in a one-day time period were colonized with MRSA. "This incidence reflects a recent finding that 8-9% of inpatients in the Chicago metropolitan area are MRSA carriers and was the impetus for the current initiative,” observed Dr. Peterson. "Our goal is to reduce the incidence of MRSA infections by 50% over the next two years among our patient population.”