Detection of Acinetobacter pittii ST220 co-producing NDM-1 and OXA-820 carbapenemases from a hospital sink in a non-endemic country of NDM.

NDM-1 is by far one of the most commonly prevalent carbapenemases in Enterobacteriaceae and Acinetobacter baumannii. Here we present an A. pittii isolate co-harboring bla and bla from a sink of a university hospital, where NDM producers have not been found in either patients or their environments.Whole-genome sequencing was performed on the HiSeq 4000 platform, and the reads were de novo assembled using the A5-miSeq Assembly pipeline. Annotation of the resulting scaffolds were performed by using the DDBJ Fast Annotation and Submission Tool (DFAST). The bla-carrying plasmid was determined.The A. pittii ST220 strain SU1805 detected from a sink strainer in the treatment room was resistant to imipenem and meropenem. Antimicrobial resistance genes bla, bla, bla, and aphA6 were found in this strain. The bla was found to be located downstream of an ISAba125 element on a plasmid pSU1805NDM with the size of 41,022 bp, GC content of 38.3% harboring 48 protein-coding genes. The aphA6 gene was also located upstream of the ISAba125 on the same plasmid. A. pittii intrinsic bla-like gene, bla was located between fxsA and yncA genes in the chromosome. The strain also harbored biofilm-associated genes such as ompA, the csu operon and their regulating genes bfmRS.This study describes the first isolation of NDM-1-producing A. pittii in Japan, and highlights the importance of proper implementation of measures against AMR for sink drainage systems since NDM producers may have already hidden in such environment in a non-endemic country of NDM.