Results on the mandatory notification of carbapenem-resistant Gram-negative bacteria, Hesse, Germany, January 2012 - April 2013

Carbapenems are important therapeutic agents for treating infections caused by multidrug-resistant Gram-negative bacteria. Mandatory reporting of carbapenem-resistant Gram-negative bacteria (CR-GN) can allow for a better understanding of the changing CR-GN burden and can help facilitate intervention. In November 2011, identification of CR-GN with acquired carbapenem resistance became notifiable in Hesse, Germany. Hesse is one of the 16 German federal states, with a population of 6.1 million. We report on CR-GN notified between 1 January and 8 April 2013, when reporting requirements were changed. During this period, 549 CR-GN were isolated from 525 patients. Of these, 67.0% (368/549) were Pseudomonas aeruginosa . The remaining 181 CR-GN comprised 59 (32.6%) K. pneumoniae , 53 (29.3%) Acinetobacter baumannii , 28 (15.5%) Enterobacter spp., 20 (11.5%) E. coli , and 21 (11.6%) other CR-GN. Seventy-three (13.3%) CR-GN were reported to harbour a carbapenemase. Fourteen different carbapenemase types were reported, with the most frequent being OXA-23 (n=18), OXA-48 (n= 16), VIM-2 (n=12), VIM-1 (n=11), and NDM (n=5). Our results suggest the widespread presence of CR-GN, a high diversity of identified carbapenemases, autochthonous transmissions, and regional differences in incidence for the different species and carbapenemases, even in the absence of major outbreaks of infection