In vitro activity of tigecycline and comparators against carbapenem-resistant Enterobacteriaceae in Africa–Middle East countries: TEST 2007–2012

Multidrug-resistant (MDR) Enterobacteriaceae are an emerging concern for healthcare providers. Infections caused by MDR pathogens are associated with increased costs, length of hospital stay, and morbidity and mortality rates. Carbapenem-resistant Enterobacteriaceae (CRE) continue to increase, and infections with these organisms are observed worldwide not only as hospital-acquired infections but also as community-acquired infections. Increasing antimicrobial resistance dictates the need for continued surveillance studies of common and MDR pathogens. The Tigecycline Evaluation Surveillance Trial (TEST) examined the susceptibility of pathogens isolated in Africa and the Middle East from 2007 to 2012. A total of 4155 Enterobacteriaceae isolates were evaluated to determine the in vitro activity and changes in resistance patterns for tigecycline and comparators. Carbapenem resistance was found in 191 (4.6%) of the isolates tested. Klebsiella pneumoniae was the most common CRE (64.9%), followed by Enterobacter cloacae (14.1%) and Escherichia coli (9.9%). Tigecycline MIC90 values (minimum inhibitory concentration required to inhibit 90% of the isolates) were 2μg/mL against all of these enteric species, with susceptibility rates of 96.8%, 92.6% and 100%, respectively. Tigecycline had in vitro activity against CRE, with a 95.3% susceptibility rate.