Carbapenem-resistant Klebsiella pneumoniae (CRKP) has become a major global public health threat. The situation of its multiple drug resistance, rapid transmission, and difficulty in treatment has brought about severe challenges to clinical anti-infection treatment. This article reviews the research progress regarding the drug resistance mechanism of CRKP since 2020, concentrating on the mutation and spread of carbapenemases, the driving function of mobile genetic elements, the hidden state of heterogeneous drug resistance, and also the synergistic effect of outer membrane porins, efflux pumps and biofilms. The results indicate that KPC enzyme variants (e.g., KPC-2, KPC-227, KPC-204) in clinically prevalent CRKP strains can affect the efficacy of novel enzyme inhibitors such as ceftazidime/avibactam, and also influence mobile genetic elements such as plasmids. This article is meant to provide references for the mechanism research, clinical detection, and the development of new treatment strategies related to CRKP.

Yingjie Li, Hao Tang. Research Progress on the Resistance Mechanisms of Klebsiella Pneumoniae. Frontiers in Medical Science Research (2026), Vol. 8, Issue 3: 72-77. https://doi.org/10.25236/FMSR.2026.080310.

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