Challenge of drug #resistance in #Pseudomonas aeruginosa: clonal spread of #NDM1-positive ST-308 within a tertiary #hospital (J Antimicrob Chemother., abstract)

[Source: Journal of Antimicrobial Chemotherapy, full page: (LINK). Abstract, edited.]

Challenge of drug resistance in Pseudomonas aeruginosa: clonal spread of NDM-1-positive ST-308 within a tertiary hospital

Ka Lip Chew, Sophie Octavia, Oon Tek Ng, Kalisvar Marimuthu, Indumathi Venkatachalam, Bernadette Cheng, Raymond T P Lin, Jeanette W P Teo

Journal of Antimicrobial Chemotherapy, dkz169,

Published: 12 May 2019




MDR Pseudomonas aeruginosa is a serious global threat to healthcare institutions. The mechanism by which drug resistance can be acquired is variable, but acquired carbapenemase production has been reported in P. aeruginosa. An investigation was performed to determine the rate and genomic epidemiology of New Delhi MBL (NDM) in β-lactam-non-susceptible isolates.


P. aeruginosa isolates from a tertiary hospital in Singapore between January 2015 and February 2018 were investigated for the presence of NDM genes.


Out of 298 pan-β-lactam-non-susceptible isolates, 31 were found to be NDM positive (10.4%). WGS demonstrated that all 31 NDM-positive isolates were clonal, belonging to ST-308. blaNDM was chromosomally inserted within an integrative and conjugative element (ICE), ICETn43716385. The NDM-P. aeruginosa isolates possessed an extensive repertoire of both cell-associated [flagella, pili, alginate/biofilm, LPS, type III secretion system (T3SS) and type VI secretion system (T6SS)] and secreted virulence factors. Antibiograms revealed higher rates of drug resistance in NDM-positive isolates compared with their non-NDM counterparts. The NDM isolates remained 100% susceptible only to colistin.


The combination of chromosomal mutations, acquired resistance genes and virulence factors likely facilitated the persistent and ongoing spread of the ST-308 clade of P. aeruginosa within the hospital. Our study illustrates the particular threat of NDM-positive P. aeruginosa in a tertiary hospital setting in the era of antimicrobial resistance.

Topic: pseudomonas aeruginosa – mutation – colistin – epidemiology – drug resistance – alginates – biofilms – bodily secretions – chromosomes – drug resistance, microbial – bacterial fimbria – flagella – genes – genome – lactams – singapore – persistence – virulence factors – antibiogram – resistance genes – type iii protein secretion system complex – whole genome sequencing


© The Author(s) 2019. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For permissions, please email:

This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (

Keywords: Antibiotics; Drugs Resistance; Beta-lactams; NDM1; Pseudomonas aeruginosa; Nosocomial outbreaks.


Published by

Giuseppe Michieli

I am an Italian blogger, active since 2005 with main focus on emerging infectious diseases such as avian influenza, SARS, antibiotics resistance, and many other global Health issues. Other fields of interest are: climate change, global warming, geological and biological sciences. My activity consists mainly in collection and analysis of news, public services updates, confronting sources and making decision about what are the 'signals' of an impending crisis (an outbreak, for example). When a signal is detected, I follow traces during the entire course of an event. I started in 2005 my blog ''A TIME'S MEMORY'', now with more than 40,000 posts and 3 millions of web interactions. Subsequently I added an Italian Language blog, then discontinued because of very low traffic and interest. I contributed for seven years to a public forum ( in the midst of the Ebola epidemic in West Africa in 2014, I left the site to continue alone my data tracking job.