[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.