Molecular analysis and ceftazidime–avibactam susceptibilities of carbapenem-resistant Klebsiella pneumoniae: Seven year experience from blood cultures of liver transplant recipients in a university hospital

Background

Carbapenem-resistant Klebsiella pneumoniae (CRKP) infection is a major cause of mortality in liver transplantation (LT) recipients.

Methods

We aimed to elucidate the molecular mechanisms of carbapenem resistance among CRKP strains and determine ceftazidime-avibactam (CZA) in vitro susceptibility in high-risk patient populations, such as LT recipients.

Results

Of the 127 LT recipients between January 2016 and 2022, no statistically significant difference was found in the in vitro sensitivity of amikacin, gentamicin, ciprofloxacin, levofloxacin, imipenem, meropenem, piperacillin–tazobactam, trimethoprim–sulfamethoxazole, tigecycline, and colistin in patients with CRKP sepsis who survived and died at 30 days, except for amikacin and meropenem, which was statistically significant at 90 days (p ≤ 0.05). Of the isolates, 120 (94.4 %) were positive for the modified carbapenem inactivation test. When the carbapenemase genes of 127 CRKP isolates were analyzed, the most common carbapenemase gene was OXA-48 (59.1 %). The presence of OXA-48, OXA-48 + NDM, NDM, IMP, and VIM genes in CRKP isolates showed a statistically significant difference with the CZA susceptibility result (p ˂ 0.05).

Conclusions

The presence of the OXA-48 resistance gene in CRKP isolates was closely associated with in vitro susceptibility to CZA, regardless of the diversity of the patient population.