Phenotypic screening and molecular characterization of carbapenemase-producing Gram-negative bacilli recovered from febrile neutropenic pediatric cancer patients in Egypt

Abstract

A total of 185 GNB were recovered from different clinical specimens, Escherichia (E.) coli (86; 46.48%), followed by Klebsiella spp. (71; 38.37%), Acinetobacter (A.) baumannii (7; 3.78%) and others including Pseudomonas spp., Enterobacter (Ent.) cloacae and Proteus spp. (21; 11.35%). It is a matter of concern that 116 out of 171 enterobacterial isolates (94.15%) showed resistance to three or more antimicrobial classes and were considered multidrug resistant. Additionally, the rate of carbapenem-resistance displayed a worrisome trend as 113 out of 171 enterobacterial isolates (66.08%) and 12 out of 14 non fermenting bacilli (85.71%) showed resistance pattern to at least one of the tested carbapenems. After performing a series of phenotypic tests for initial screening of potential carbapenemase producers, molecular characterization to the 29 extracted plasmids were subjected to PCR using 5 common carbapenemase primers). The results revealed that bla(OXA-48) was the most prevalent 17 (58.62%), followed by bla(NDM) 8(27.58%), then bla(VIM) 3 (10.3%) and bla(KPC) 2 (6.89%).