First detection and origin of multi-drug resistant Klebsiella pneumoniae ST15 harboring OXA-48 in South America.

Objectives: The emergence and spread of carbapenem resistant clones is of major concern for global health. This study aimed to characterize the first detected Klebsiella pneumoniae ST15 harboring the epidemic carbapenemase OXA-48 in South America.

Methods: During a routine colonization screening with carbapenem-resistant bacteria, one K. pneumoniae strain (CGHM01) was isolated from the urine of a hospitalized patient suffering from a neurodegenerative disease in Uruguay. We used long-read whole-genome sequencing and a phylogenomic approach to characterize the emergence of K. pneumoniae CGHM01.

Results: K. pneumoniae CGHM01 is a multi-drug resistant strain carrying an IncL/M plasmid that encodes the carbapenemase gene bla within the Tn1999.2 transposon. Also, it carries an IncR plasmid harboring a class I integron with an array of antibiotic resistance genes including the extended-spectrum beta-lactamase bla. Two copies of bla were also inserted in different positions of the chromosome. CGHM01 belongs to a ST15 sublineage that likely originated in continental Spain around 2012.

Conclusions: The asymptomatic carriage of this strain in the urinary tract warns of difficulties for detection and reporting of emerging carbapenem-resistant clones in new geographic areas where these are not endemic.