Multidrug-resistant organisms (MDRO): Cost-effective analysis of horizontal vs. vertical surveillance

Introduction: Multidrug-resistant organisms (MDRO) are still a serious public health problem in healthcare facilities and are a major cause for morbidity and mortality in hospitalized patients. There is currently no consensus for the most effective surveillance approach for MDRO management. The objective of this study is to compare focused enhanced surveillance for populations at high-risk for MDRO colonization to the current vertically oriented (organism focused) surveillance strategy. A cost-effective analysis will be performed to determine which approach is more economical.

Methods: Electronic medical record surveillance was performed to randomly identify 100 high-risk patients. Nursing staff in the UPMC-Mercy ICUs and infection control department gathered samples from patients for the following MDRO: Methicillin-resistant Staph aureus (MRSA), Vancomycin resistant Enterococci (VRE), Carbapenem resistant enterobactericiae (CRE) and extended spectrum Beta lactamase producing organisms (ESBL). Specimens were analyzed, and the results were recorded. Chart abstraction collected patient characteristics, severity index and comorbidity index. Stata SE 15.1 was used for data analysis to compare the current surveillance method to the horizontal approach. TreeAge software was used to conduct a cost-effective analysis to compare the two approaches. 

Results: From Oct 1st, 2017 through Nov. 30th, 2017 there were total of 155 eligible patients identified through EMR surveillance. We screened 74 patients who met our clinical criteria and 26 patients who met our 7-day length of stay criterion. There were 52% men in our cohort, with an average age of 60.1 years. The mean severity index was 38.8 and the mean comorbidity index was 4.4.  There was evidence of MDRO (CRE, ESBL, VRE & MRSA) in 30% of patients with high-risk clinical criteria and 27% in 7-day LOS patients, as compared to 10% MRSA captured using the current screening strategy. Horizontal surveillance was found to be the cost-effective approach.

Discussion: Clinical-based horizontal surveillance is a more effective way of identifying MDRO colonization and infection. The next step in our research is to include a larger patient sample to verify these data results.

Advisor: Lawrence Kingsley