Molecular Characterization of NDM-Type Genes in Carbapenem-Resistant Gram-Negative Bacteria Isolated from Clinical Samples in Al-Najaf City, Iraq

An infection that is difficult to treat is caused by Gram-negative bacteria that are resistant to carbapenems. Additionally, these infections are associated with elevated rates of mortality and illness. The aim of this study find out how the NDM gene moves between bacteria that are Gram-negative and not sensitive to carbapenem. This study looked at 1,031 clinical samples from different places, 382/1031 (37.05%) without bacterial growth, compared with 649/1031 (62.94%) were bacterial growth, which involved 172 /649 (26.50 %) Gram-positive bacteria and 477/649 (73.49%) Gram-negative bacteria. In the same context, the infection source was 740/1031 (71.77 %) from female patients, while 291/1031 (28.22%) from male patients. According to results of carbapenim disk susciptibilty, this work recorded among 477/649 (73.49%) Gram negative bacteria only 114/477( 23.89%) recorded as carbapenem-resistant gram-negative isolates, PCR data revealed that only 30 /114 ( 26.315% ) isolates of which carried NDM genes involved 8(7.01%) for both Acinetobacter baumannii and Escherichia coli isolates, while 6(5.26%) and 3(2.63%) for isolated strains of Klebsiella pneumoniae and Pseudomonas aeruginosa, as 2(1.75%) for both Enterobacter cloacae and Burkholderia cepacia isolated Serratia marcescens, and finally one (0.87%) for isolated Serratia marcescens. Molecular data showed that all 30 isolates had the CTX-M, MphA, and aac(6′)-Ib-cr genes. But OXA and SHV were 27/30 (90%) off. There were no KPC, GIM, or SPM genes, but 25 out of 30 (83.33%) had AmpC genes, and 5 out of 30 (16.66%) had IMP genes.