Multidrug-Resistant Organisms (MDRO) in Post-Acute Care: Dynamics From Admission Through Discharge

Abstract

Background. Post-acute care (PAC) bridges patient care from hospital discharge to community reentry. However, this transition time is rapidly shortening. Methods. We actively surveyed MDRO colonization (methicillin-resistant Staphylococcus aureus [MRSA], vancomycin-resistant Enterococcus [VRE], and quinolone, ceftazidime, or imipenem-resistant Gram-negative bacteria [R-GNB]) in 651 patients admitted to 6 largely inner-city PAC facilities in Southeastern Michigan. Nares, groin, oropharynx, hands, rectum, wounds, and devices (urinary catheter/feeding tube) were cultured at enrollment, 2 weeks, and monthly for 180 days or until discharge. We used logistic and Poisson regression, clustered by facility. Results. We enrolled 651 patients [1410 total visits; 14,026 patient days]. The mean PAC length of stay was 20 person-days (2.1 visits). Enrollees entered PAC after a mean hospital stay of 5.6 days. Half of all patients were colonized with an MDRO at baseline (332 of 651 [51.0%]) and at the final visit (322 of 651 [49.5%]); most often with VRE (baseline 33.2%; final visit 29.7%) (Figure 1). Excluding 253 patients with no follow-up (where the admission visit was also the final visit), final visit MDRO colonization was 48.2% (VRE 28.9%). Among patients at-risk (>1 visit and not colonized with all three MDROs on admission), 72 of 385 (18.7%) acquired a new MDRO during their PAC stay, most often R-GNB (43 of 317 at-risk [13.6%]). Functional disability, devices, and prolonged hospitalization (>2 weeks pre-PAC) were associated with MDRO colonization at baseline and discharge (Figure 2). Devices (IRR = 1.85 [95% CI, 1.15-2.99] P = 0.012) and prolonged hospitalization Conclusion. In this first large-scale prospective cohort study, we found an extraordinary burden of MDROs at both PAC entry and exit. The dynamics of MDRO colonization include a very mild loss of VRE; however, that was offset by R-GNB acquisition. Increasingly brief PAC stays may have caused an unintended wave of patients discharged home carrying MDROs. Prior assumptions that intervening on risk factors will naturally clear MDROs before discharge should be re-examined in this new era of short PAC stays.