[Colistin resistance in carbapenem-resistant Klebsiella pneumoniae isolates from a pediatric hospital from Corrientes, Argentina].

BACKGROUND

There is an increase of carbapenem-resistant Klebsiella pneumoniae (CRKP) infections in the pediatric population and epidemiological data are limited.

AIM: To calculate the frequency of CRKP in pediatric patients, to determine the in vitro activity of colistin and to detect the presence of mcr-1 gene in said isolates.

METHODS

220 isolates of K. pneumoniae were studied in a pediatric hospital between January 2018 and December 2019. Antimicrobial susceptibility was determined by microdilution in broth according to guidelines of CLSI and EUCAST. The genes blaKPC, blaNDM, blaIMP, blaVIM, blaOXA-48 and mcr-1 were detected by polymerase chain reaction (PCR).

RESULTS

9.5% (n: 21) of the isolates were characterized as CRKP, where was observed a resistance to colistin of 47.6% (10/21) with values of MIC50 of 2 μg/mL and MIC90 of ≥ 4 μg/mL. In 100% of CRKP strains the blaKPC gene was detected and the mcr-1 gene was not found. The resistance profile to other antimicrobials was as follow: gentamicin 100% (n: 21), trimethoprim/sulfamethoxazole 100% (n: 21), ciprofloxacin 100% (n: 21), amikacin 19% (n: 4). All of the isolates were sensitive to ceftazidime/avibactam and tigecycline.

CONCLUSION

This study demonstrates a significant value of resistance to colistin in pediatric patients compared to other last line antimicrobial such as ceftazidime/avibactam and tigecycline.