Narrowing the gap between research and clinical practice: Molecular Epidemiology of Multidrug resistant gram-negative infections and the effectiveness of new bacterial agents

Yükseköğretim Kurumları Destekli Proje, 2022 - 2023

Background

Carbapenem resistance has been a challenge for treating nosocomial infections caused by

gram-negative bacteria. We aimed to describe clinical characteristics of Klebsiella

pneumoniae infections whilst surveying their antimicrobial resistance rate and molecular

characteristics.

Methods

KAPSAR is a multicentric prospective cohort consisting of 16 hospitals from nine cities in

Turkey. Inclusion criteria were a clinical diagnosis of sepsis and/or pneumonia in adult

patients admitted to the hospital and laboratory evidence of Klebsiella pneumoniae from

respiratory or blood samples. Co-infections with other bacteria were excluded. Demographic

and clinical data were collected from all patients. Samples from patients with carbapenemresistant

bacterial growth were collected (N=186) and analyzed for antibiotic resistance by

broth microdilution susceptibility assay and PCR was performed to screen for OXA-48,

NDM-1, KPC-1.

Results

Data from 295 patients was collected for 11 months between January 1st, 2022 and

December 1st, 2022. Among these patients, 217 (73.6%) had carbapenem-resistant Klebsiella

pneumoniae infection. Mortality rate was increased for patients with advanced age (p<0.001),

pneumonia without bacteremia (p<0.001), myocardial infarction (p=0.032), cerebrovascular

incident (p=0.030), liver disease (p=0.037). Although procalcitonin, C-reactive protein, white

blood cell count, and creatinine measurements were observed to be higher in the fatal cases,

we were able to show no statistical significance (p>0.05). However, patients infected with

carbapenem-resistant (p<0.001) and colistin-resistant (0.005) strains had higher mortality.

Molecular surveillance showed positivity of 69.4% for OXA-48, 21.0% for NDM-1, 9.1% for

KPC-1. Among carbapenem-resistant isolates resistance rates were 100% for piperacillintazobactam,

98.4% for ceftolozane-tazobactam, 39.2% for ceftazidime-avibactam, and 32.3%

for colistin. In NDM-1 positive samples, colistin resistance was higher (34.0%), however

ceftazidime-avibactam resistance was lower (24.5%).

Conclusions

Carbapenem-resistant Klebsiella pneumoniae infection is rising. The alternative antibiotics

should be increased. One of the new drugs ceftazidime-avibactam should be used timely for

the carbapenem-resistant Klebsiella pneumoniae infections. The surveillance of antimicrobial

resistance is critical for selection of the optimum antibiotic choices.