Expensive as it might be, such a program can actually wind up saving money by preventing disease caused by the pathogen, said Lance Peterson, MD, of NorthShore Health System in Evanston, Ill.
Peterson told colleagues at the Interscience Conference on Antimicrobial Agents and Chemotherapy that, on average, seven of every 100 patients with MRSA colonization go on to develop disease.
"The biggest risk factor for MRSA infection is to be colonized," he said.
So, starting in August, 2005, the three hospitals in the NorthShore system used real-time polymerase chain reaction testing to screen incoming patients for colonization with MRSA.
Patients whose nasal passages tested positive for the pathogens were isolated and treated with mupirocin (Bactroban) for five days. Staff treating them used gowns and gloves for contact precautions, he said. Patients were also given two antiseptic baths.
The immediate clinical result was a 70% drop in MRSA infection among patients, Peterson said.
The molecular PCR test is faster than traditional cell culture methods, he said, yielding results on average within 15 hours after a nasal swab. But it is also significantly more expensive.
In addition, isolating colonized patients added costs, he said, owing to increased nursing care.
The bottom line was that the program cost the three facilities in the system -- two teaching hospitals and one community hospital -- $600,000 a year, Peterson said.
On the other hand, each MRSA infection was estimated to cost $24,000, only half of which would be recovered by the hospital from insurers, he said.
So the savings associated with preventing MRSA infection amounted to $1.8 million a year, Peterson said.
Peterson said state mandates that insist on screening intensive care or high-risk patients aren't broad enough and "most likely won't work."
"The bottom line for us is that if you want to have a successful MRSA reduction program, you have to have a very aggressive, very rapid and broad MRSA screening program," he said.
Peterson said other countries have successfully reduced the prevalence of MRSA colonization, as well as the incidence of infection. In the U.S., he said, such a result is "probably going to take a national program."
Although the Evanston program has been remarkably successful, it hasn't yet become the model for many other hospitals, said John Boyce, MD, of the Hospital of Saint Raphael in New Haven, Conn.
The results are "impressive and kind of hard to argue with," he said, but many hospital administrators are likely to look at the increased costs and recoil.
One the other hand, if one or two more studies confirm the result, "you're going to see a lot of traction," he said.
Boyce added that his hospital has not followed the NorthShore lead, although it has had smaller screening programs for several years.
Peterson did not report any support for his data.
He said he had financial links with Cepheid, NorthShore, GeneOhm, MicroPhage, Nanosphere, NIAID, Roche, 3M, and Washington Square Health Foundation.
Zalman S. Agus, MD Emeritus Professor
University of Pennsylvania School of Medicine and Dorothy Caputo, MA, RN, BC-ADM, CDE, Nurse Planner
Interscience Conference on Antimicrobial Agents and ChemotherapySource Reference: Peterson LR "Is Molecular Screening for MRSA Colonization Worth the Cost? Case in Favour" ICAAC 2009; Session 0-36.