An ICU’s method of testing for methicillin-resistant Staphylococcus aureus (MRSA) should be paired with its patient isolation policy, according to researchers at the University of Colorado at Denver.
In an ICU with all patients preemptively isolated, it is worth the added expense to opt for the polymerase chain reaction (PCR) test – which generates results in a few hours – so that patients negative for the infection can be moved out of isolation more quickly, wrote Melanie D. Whittington, PhD, and her coauthors. But if the ICU is only isolating MRSA-positive patients, the authors instead recommend the less expensive but slower chromogenic agar 24-hour testing.
The other two MRSA tests the researchers assessed – conventional culture and chromogenic agar 48-hour testing – are less expensive. But when paired with either ICU isolation policy, those tests lead to excessive inappropriate isolation costs while waiting for the results, the study investigators cautioned (Am J Infect Control. 2017 Jan 23. doi: 10.1016/j.ajic.2016.12.014).
Adding together the cost per patient of the test, the “appropriate isolation costs,” and “inappropriate isolation costs,” the universal isolation policy is least expensive per patient with PCR, at $82.51 per patient. With conventional culture, which can take several days, this cost ballooned to $290.11 per patient, with high inappropriate isolation costs.
Doing the same math with the more targeted isolation policy, the least expensive screening method was the 24-hour chromogenic agar, at $8.54 per patient, while the expense of the PCR test made it the most expensive method when paired with this isolation policy, at $30.95 per patient.
“With knowledge of the screening test that minimizes inappropriate and total costs, hospitals can maximize the efficiency of their resource use and improve the health of their patients,” Dr. Whittington and her coauthors wrote.
The authors reported no conflicts of interest.