Colonization of the gut by Klebsiella pneumoniae and its multidrug-resistant strains is well marked in preterm neonates.

BACKGROUND: The colonization of preterm neonates by multidrug-resistant Enterobacteriaceae, especially in neonatal intensive care units (NICUs), remains poorly understood despite its potential role in healthcare-associated transmission. This study addresses this gap by characterizing gut colonization by Enterobacteriaceae, focusing on carbapenem-resistant Klebsiella pneumoniae in preterm neonates.

RESULTS: Samples of preterm neonates' stool were cultured on eosin methylene blue (EMB) agar, followed by biochemical identification, 16S rRNA gene sequencing, and antibiotic susceptibility testing using the VITEK 2 system. All preterm neonates aged 2 weeks or older exhibited colonization by enterobacteria. K. pneumoniae was the most prevalent species, identified in 56.2% (9/16) of samples, with K. quasipneumoniae present in an additional 6.3% (1/16). Two K. pneumoniae isolates were multidrug-resistant; one exhibited carbapenem resistance, and one showed intermediate susceptibility. These strains were also resistant to multiple other antibiotics. Escherichia coli was detected in 50% (8/16) of cases but exhibited no carbapenem resistance.

CONCLUSIONS: This study demonstrates that preterm neonates in NICUs can harbor multidrug-resistant K. pneumoniae in their gut, highlighting the gut as a potential reservoir and source of CRE (carbapenem-resistant Enterobacteriaceae) dissemination. These findings stress the need for enhanced surveillance, strict infection control practices, and strategies to prevent gut colonization and fecal-oral transmission of multidrug-resistant bacteria in vulnerable neonatal populations. All strains of K. pneumoniae, including those resistant or with intermediate resistance to carbapenems, displayed widespread sensitivity to gentamicin (GM) and tigecycline (TGC) in vitro, suggesting potential clinical utility, though further evaluation is warranted.