An exploratory cost-effectiveness analysis of methicillin-resistant Staphylococcus aureus nares PCR in pediatric pneumonia and tracheitis

Objective: To estimate the cost-effectiveness of methicillin-resistant Staphylococcus aureus (MRSA) nares poymerase chain reaction (PCR) use in pediatric pneumonia and tracheitis. Methods: We built a cost-effectiveness model based on MRSA prevalence and probability of empiric treatment for MRSA pneumonia or tracheitis, with all parameters varied in sensitivity analyses. The hypothetical patient cohort was <18 years of age and hospitalized in the pediatric intensive care unit for community-acquired pneumonia (CAP) or tracheitis. Two strategies were compared: MRSA nares PCR-guided antibiotic therapy versus usual care. The primary measure was cost per incorrect treatment course avoided. Length of stay and hospital costs unrelated to antibiotic costs were assumed to be the same regardless of PCR use. Both literature data and expert estimates informed sensitivity analysis ranges. Results: When estimating the health care system willingness-to-pay threshold for PCR testing as $140 (varied in sensitivity analyses) per incorrect treatment course avoided, reflecting estimated additional costs of MRSA targeted antibiotics, and MRSA nares PCR true cost as $64, PCR testing was generally favored if empiric MRSA treatment likelihood was >52%. PCR was not favored in some scenarios when simultaneously varying MRSA infection prevalence and likelihood of MRSA empiric treatment. Screening becomes less favorable as MRSA PCR cost increased to the highest range value of the parameter ($88). Individual variation of MRSA colonization rates over wide ranges (0% – 30%) had lesser effects on results. Conclusions: MRSA nares PCR use in hospitalized pediatric patients with CAP or tracheitis was generally favored when empiric MRSA empiric treatment rates are moderate or high.