Multidrug-resistant bacteria in travellers hospitalized abroad: prevalence, characteristics, and influence on clinical outcome

Abstract

Worldwide, the burden of multidrug-resistant bacteria (MDR) is increasing, especially in the hospital setting. To explore characteristics and clinical relevance of MDR obtained from travellers transferred from hospitals abroad. This retrospective study included patients transferred from hospitals abroad to the University Hospital Zurich, Switzerland, who routinely underwent admission screening for possible colonization with meticillin-resistant Staphylococcus aureus (MRSA), extended-spectrum beta-lactamase-producing bacteria (ESBL) and multidrug-resistant Gram-negative bacteria (MR Gram negative). Forty-six (17%) of 259 subjects were found to be colonized with MDR and nine (3.5%) patients to be infected. Thirty-three (12%) patients were colonized with one bacterial species, 12 (4.6%) with two, and three (1.2%) were colonized with three different bacterial species. In total, 36 ESBL, 21 MR Gram-negative and three MRSA isolates were detected. Escherichia coli (N = 18, 30%), Klebsiella pneumoniae (N = 14, 23%) and Acinetobacter baumannii (N = 14, 23%) were most frequently isolated. The most common sites of detection were skin (97%) and respiratory tract (41%). Being colonized contributed to an increased length of ICU stay [median (range): 8 (1-35) vs 3.5 (1-78) days; P = 0.011]. In-hospital mortality in patients colonized with MDR (10.9%) was higher than in uncolonized patients (2.3%, P = 0.018). Being colonized with MDR was associated with death (adjusted odds ratio: 5.176; 95% confidence interval: 1.325-20.218). A substantial proportion of patients transferred from abroad are colonized with MDR, a fact which is associated with poor clinical outcome.