First Report of bla CTX-M-167, bla SHV-1, and bla TEM-1B Carrying Klebsiella pneumonia Showing High-Level Resistance to Carbapenems

Shirong Li; Siquan Shen; Li Ding; Renru Han; Yan Guo; Dandan Yin; Ming Guan; Fupin Hu

doi:10.3389/fmicb.2022.916304

First Report of bla _CTX-M-167, bla _SHV-1, and bla _TEM-1B Carrying Klebsiella pneumonia Showing High-Level Resistance to Carbapenems

Front Microbiol. 2022 Jul 7:13:916304. doi: 10.3389/fmicb.2022.916304. eCollection 2022.

Authors

Shirong Li¹, Siquan Shen^{2

3}, Li Ding^{2

3}, Renru Han^{2

3}, Yan Guo^{2

3}, Dandan Yin^{2

3}, Ming Guan¹, Fupin Hu^{2

3}

Affiliations

¹ Deptartment of Laboratory Medicine, Huashan Hospital, Fudan University, Shanghai, China.
² Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, China.
³ Key Laboratory of Clinical Pharmacology of Antibiotics, Ministry of Health, Shanghai, China.

Abstract

The prevalence of carbapenem-resistant Klebsiella pneumoniae is increasing. Although carbapenemase production is the main resistance mechanism of K. pneumonia to carbapenems, there are still some reports of non-carbapenemase-producing K.pneumoniae showing high-level resistance to carbapenems. In this study, we had also isolated a carbapenemase-negative carbapenem-resistant K. pneumoniae L204 from a patient with an asymptomatic urinary tract infection. Species identification was performed using MALDI-TOF MS, and carbapenemase-encoding genes were detected using both NG-test carba-5 and whole-genome sequencing. Antimicrobial susceptibility testing was performed by the broth microdilution method according to CLSI guidance. The results of antimicrobial susceptibility testing indicated that K. pneumoniae L204 was resistant to meropenem (MIC = 16 mg/L) and imipenem (MIC = 4 mg/L), but susceptible to ceftazidime-avibactam (MIC = 8 mg/L). Through whole-genome sequencing, several resistance genes had been identified, including bla _TEM-1B, bla _CTX-M-167, bla _SHV-1, aac(6')-1b-cr, qnrS, aadA16, tet(A), fosA, sul1, and mph(A). The efflux pump inhibition testing showed that the efflux pump was not involved in the resistance mechanism to carbapenems. The result of the conjugation experiment indicated that the plasmid with bla _CTX-M-167 and bla _SHV-1 was transferrable. The sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) demonstrated that K. pneumoniae L204 only contained outer membrane porin OmpK35.

Keywords: Klebsiella pneumoniae; blaCTX–M–167; blaSHV–1; blaTEM–1B; carbapenem.