RGCB team does sequencing of colistin-resistant bacteria

In a first, the whole-genome sequence done by the Antimicrobial Research (AMR) team at the Rajiv Gandhi Centre for Biotechnology (RGCB), Thiruvananthapuram, on the hyper-virulent strain of colistin-resistant bacteria Klebsiella pneumoniae isolated last year has made it to an international research journal.

Colistin is the high-end antibiotic used against virulent forms of bacteria. The bacteria were isolated by a dedicated AMR team in the District General Hospital, Ernakulam.

The RGCB, a research collaborator for the State, had found sequence type (ST) of the isolate K. pneumoniae strain belonging to ST78. “To our knowledge, this is the first report of a multidrug-resistant (MDR) K. pneumoniae with high colistin resistance,” according to Sabu Thomas, faculty scientist and principal investigator from the RGCB.

The research paper on the gene sequence and the variant types were published in the Journal of Global Antimicrobial Resistance in April 2019. Both the whole-genome sequencing and getting it published are a first for the State, said Dr. Thomas.

New therapies

Elaborating on the findings, he said the genome sequence of bacteria will provide a platform to validate the effect of MDR gene and the pattern of co-resistance in various types. It also helps to understand and develop new therapies by identifying suitable drug targets.

The data can also be used to study microbes showing similar antimicrobial resistance and susceptibility, said Dr. Thomas. The isolate was resistant to all classes of antibiotics tested and showed intermediate susceptibility to tigecycline, a last-resort antibiotic.

The bacteria were isolated by the AMR team in the GH from the blood sample of a female patient with chronic kidney disease admitted to the nephrology intensive care unit.

This research work became possible because of the action plan on antimicrobial resistance taken up by the State making the GH a nodal centre for AMR strategy. Rajeev Sadanandan, Additional Chief Secretary, told The Hindu that the research activity shows the strength of the Health Services in taking up academic programmes. The paediatric department headed by P.S. Sivaprasad had coordinated the AMR work in the GH.

A major hurdle

Global spread of antimicrobial resistance is the major hurdle in providing effective treatment, said Dr. Thomas. Since it is grouped as a ‘priority pathogen’ by the World Health Organization (WHO) with a critical urgency of need for new antibiotics, antimicrobial resistance in this bacteria brings a big threat to humans causing community and hospital-acquired infections both in healthy individuals and immuno-compromised patients, he added.