Part one of a two-part series.
Whether or not it is mandated by state law, some healthcare institutions are turning to active surveillance cultures (ASC) of all or certain high-risk patients, as well as placing them under contact precautions – all in an effort to curb or eliminate the multidrug-resistant organisms (MDROs) that can trigger healthcare-acquired infections (HAIs). The issue is fraught with emotion, however, as proponents and detractors of ASC each assert what they believe to be strong arguments.
It is also a complex issue. Edmond, et al. (2008a) enumerate the challenges associated with ASC: “Ethical challenges involve a conflict between the interests of the individual patient and the patient population not already colonized with the organism. For healthcare systems, active surveillance increases the complexity of bed management, exacerbating problems with patient placement, patient throughput, emergency department overcrowding and ambulance diversion for some hospitals. It also poses ethical dilemmas regarding societal resource allocation. Investing in an unproven or marginally beneficial quality improvement activity such as this must be balanced against other public health priorities competing for scarce resources.”
The impetus for the debate is methicillin-resistant Staphylococcus aureus (MRSA) and the misery it causes in terms of human life lost and costs associated with the treatment of complications and additional bed days. Calfee and Salgado, et al. (2008) describe the burden of HAIs caused by MRSA in acute-care facilities: “In the United States, the proportion of hospital associated S. aureus infections that are caused by strains resistant to methicillin has steadily increased. In 2004, MRSA accounted for 63 percent of S. aureus infections in hospitals.” They also describe the risk of a substantial proportion of MRSA colonized patients subsequently developing a MRSA infection: “One study of persons in whom MRSA colonization had been identified during a previous hospital stay reported that the risk of developing an MRSA infection, such as bacteremia, pneumonia or soft tissue infection, within 18 months after detection of MRSA colonization was 29 percent.”
Calfee and Salgado, et al. (2008) also describe the reservoir for MRSA transmission: “In healthcare facilities, antimicrobial use provides a selective advantage for MRSA to survive, and transmission occurs largely through patient to patient spread. MRSA colonized and infected patients readily contaminate their environment, and healthcare personnel coming into contact with patients or their environment readily contaminate their hands, clothing and equipment.” Calfee and Salgado, et al. (2008) further explain that, “The reservoir for transmission of MRSA is largely composed of two groups of patients—those with clinical MRSA infection and a much larger group of patients who are merely colonized. Various detection methods can be used to identify one or both of these groups: Routine review of data from clinical specimens: Clinically infected patients and some asymptomatically colonized patients can be detected when MRSA is isolated from a clinical specimen sent to the microbiology laboratory; and review of active surveillance testing data; active surveillance testing for MRSA is defined as performing diagnostic testing for the purpose of detecting asymptomatic MRSA colonization.”
The easy case for or against ASC can be made from perusing the medical literature, depending on what one wishes to find and how to interpret it. One individual advocating for ASC is Lance Peterson, MD, at NorthShore University Health System in Chicago; he presented research at last fall’s annual Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC) showing that hospital-acquired MRSA can be largely prevented by identifying carriers of the organism when patients are admitted to the hospital and then initiating aggressive isolation procedures, even if patients are not experiencing disease symptoms but are colonized by the bacteria. Peterson says if hospitals are not aggressive in conducting isolation programs with patients carrying MRSA, the facility’s infection control program is doomed to fail. Peterson reports that the ambitious program initiated at his hospitals in 2005 resulted in a 70 percent reduction in MRSA infections rates, and even though the costs associated with the program added to the hospital budget, the resulting savings in preventing infections was triple the cost. (Peterson, 2009)
