Attributable costs and length of stay of an extended-spectrum beta-lactamase-producing Klebsiella pneumoniae outbreak in a neonatal intensive care unit

OBJECTIVES: To determine the costs of the interventions aimed at controlling the 4-month outbreak and to determine the attributable length of stay (LOS) associated with infection and colonization with extended-spectrum beta-lactamase-producing Klebsiella pneumoniae. DESIGN: A retrospective cost analysis was conducted from the hospital perspective. A micro-costing approach was employed. The LOS of four groups of hospitalized patients were compared with each other. National Perinatal Information Center criteria were used to stratify infants for severity of risk. The LOS of each group was compared with that of a national sample of similarly stratified infants. SETTING: A level III-IV, 45-bed neonatal intensive care unit. PATIENTS: Infant groups were infected (n = 8), colonized (n = 14), concurrent cohort (n = 54), and prior cohort (n 486). RESULTS: The cost of the outbreak totaled $341,751. The largest proportion of costs was related to healthcare worker time providing direct patient care (2,489 hours at a cost of $146,331). Infected and colonized neonates had longer LOS than either the concurrent cohort or the prior cohort (P < .001). Compared with the national sample, infected infants had a 48.5-day longer mean LOS (95% confidence interval [CI95], 1.7 to 95.2), whereas the prior cohort's mean LOS was 6 days shorter (CI95,-9.4 to -2.9). CONCLUSIONS: This study increases the understanding of the burden of these multidrug-resistant organisms. Further research is needed to estimate the societal costs of these infections and the cost-effectiveness of preventive interventions.