Development of colonization/infection with carbapenem resistant Klebsiella pneumoniae and distribution of carbapenemase types in adult intensive care units

The incidence of infections caused by carbapenem-resistant Enterobacteriaceae is increasing worldwide and, mortality rates are high. Rapid detection of infections and colonized patients with these strains is very important for the implementation of infection control protocols. In this study, we aimed to investigate the colonization/infection rates and carbapenemase types due to carbapenem-resistant Klebsiella pneumoniae in patients hospitalized in adult intensive care units. Carbapenem-resistant K.pneumoniae (CRKP) strains isolated from the rectal swab and clinical samples between JuneDecember 2017 from patients hospitalized in adult intensive care units were included in this study. Antibiotic susceptibility of the strains was studied by VITEK2 automated system. In the phenotypic determination of carbapenemases, NG CARBA-5 immunochromatographic method was studied according to the manufacturer’s recommendations. The presence of carbapenemase genes (OXA-48, IMP, VIM, KPC, NDM) was investigated by PCR method using specific primers. During to study period, 51 CR-Kp from the screening culture of 344 patients and 30 CR-Kp from clinical samples were produced. More than one gene positivity was observed in at least one-third of the patients. Seventeen patients who developed infection were colonized with this microorganism in the past three months. Four patients with infection had negative screening cultures, while nine patients developed CRKP infection without screening culture. Accordingly, colonization/infection rate in our intensive care units was determined as 33.3%. In our intensive care units, OXA-48 and NDM enzymes are 60 %. Interestingly, the KPC type enzyme, which we did not observe in previous years, was detected from both clinical and screening cultures. The infection / colonization rate in our intensive care units is not negligible and, approximately one third of colonized patients may develop the infection.