Emergence of New Delhi metallo-beta-lactamase 1 and other carbapenemase-producing Acinetobacter calcoaceticus-baumannii complex among patients in hospitals in Ha Noi, Viet Nam

Abstract

Acinetobacter baumannii is an important cause of multidrug-resistant hospital acquired infections in the world. Here, we investigate the presence of NDM-1 and other carbapenemases among carbapenem-resistant A. baumannii isolated between August 2010 and December 2014 from three large hospitals in Hanoi, Vietnam. We identified 23/582 isolates (4 %) (11 from hospital A, five from hospital B, and seven from hospital C) that were NDM-1 positive, and among them 18 carried additional carbapenemase genes, including seven isolates carrying NDM-1, IMP-1, and OXA-58 with high MICs for carbapenems. Genotyping indicated that NDM-1 carrying A. baumannii have expanded clonally in these hospitals. Five new STs (ST1135, ST1136, ST1137, ST1138, and ST1139) were identified. One isolate carried NDM-1 on a plasmid belonging to the N-repA replicon type; no NDM-1-positive plasmids were identified in the other isolates. We have shown the extent of the carbapenem resistance and the local clonal spread of A. baumannii carrying NDM-1 in these hospitals; coexistence of NDM-1 and IMP-1 is reported for the first time from Vietnam here, and this will further seriously limit future therapeutic options.

Occurrence and characterization of carbapenem‐resistant Gram‐negative bacilli: A collaborative study of antibiotic‐resistant bacteria between Indonesia and Japan

“…A study from another city in Japan showed that 20 CPE were included in two STs (ST2 and ST246), and 17 (85%) were bla OXA‐23 type, similar to results in Gunma University Hospital, Japan . This is different from Vietnam, where NDM is dominant among CRE, similar to Indonesia . Interestingly, a recent study in Jakarta, the capital city of Indonesia, showed that all 14 carbapenem non‐susceptible isolates from an ICU harbored the OXA gene (13 OXA‐66 and one OXA‐68) …”

“…Saharman et al . in Jakarta, Indonesia, reported that the isolation rate of CR‐ A. baumannii in the ICU increased alongside the length of hospitalization up to 22 days . This suggests that longer hospitalization increases the risk of transmission of CR‐bacteria.…”

“…Up to 34 kinds of antibiotics per patient were consumed for those patients. The risk factors for carbapenem resistance, including mechanisms described above, include longer hospital stay, more use of antibiotics and the seriousness of the disease …”

“…20 The present study partly differs from studies in Japan. [21][22][23][24][25][26][27][28][29][30][31][32][33][34] Koyano et al found that 13 (0.8%) of 1704 isolates from Tokyo were CPE, and mostly dominated by the IPM-1 gene (n = 12, 92.3%). 21 A study from another city in Japan showed that 20 CPE were included in two STs (ST2 and ST246), and 17 (85%) were bla OXA-23 type, 22 similar to results in Gunma University Hospital, Japan.…”

“…23 This is different from Vietnam, where NDM is dominant among CRE, similar to Indonesia. 24 Interestingly, a recent study in Jakarta, the capital city of Indonesia, showed that all 14 carbapenem non-susceptible isolates from an ICU harbored the OXA gene (13 OXA-66 and one OXA-68). 25 NDM-1-producing Enterobacteriaceae might carry other mechanisms for antibiotic resistance with various b-lactamases and other types of carbapenemases resistant to other antimicrobials.…”