Clinical and Molecular Characteristics of Carbapenemase-Producing E. coli Strains from Patients with Biliary System Diseases and Hematological Malignancies

Abstract

Purpose

This study aims to investigate the clinical and molecular characteristics of carbapenemase-producing E. coli strains (CPECO).

Patients and Methods

We collected 38 non-repetitive CPECO strains, identified them using MALDI-TOF, and assessed their antimicrobial susceptibility via the VITEK-Compact II system. We gathered demographic and clinical patient data. Phenotypic assays were employed to detect carbapenemase types. Polymerase chain reaction (PCR) was utilized to identify the carbapenemase genes. Seven housekeeping genes were amplified and sequenced to determine the multilocus sequence typings (MLSTs).

Results

These CPECO strains, primarily isolated from aseptic site and stool screening specimens, exhibited significant resistance to most clinical antibiotics, except for tigecycline and amikacin. Most patients had underlying medical conditions and underwent invasive procedures. There were significant differences among patients concerning the presence of malignancies, digestive system disorders, endoscopic retrograde cholangiopancreatography (ERCP) surgeries and abdominal drainage tubes. However, no significant differences were observed among patients regarding conditions, including hypertension, diabetes, respiratory diseases, urinary diseases and cardiovascular diseases, as well as invasive procedures such as deep venous catheterization, endotracheal intubation and gastrointestinal catheterization. Metallo-β-lactamase was primarily responsible for carbapenem resistance, including bla_NDM-5(24/38), bla_NDM-1(5/38), bla_NDM-9(1/38) and bla_IMP-4(1/38). Additionally, 7 CPECO strains carried bla_KPC-2. The distribution of CPECO sequence types (STs) was diverse, with seven strains being ST131, six strains being ST410, three strains each of ST1196 and ST10, although most STs were represented by only one strain.

Conclusion

CPECO infections in patients with biliary system diseases may result from intestinal CPECO translocation, with ERCP surgery potentially facilitating this. Meanwhile, malignant tumor was found to be a significant factor affecting CPECO infections in patients with hematological diseases. bla_NDM-5, bla_NDM-1 and bla_NDM-9 were primarily responsible for carbapenem resistance in CPECO strains. The emergence of carbapenem-resistant ST131 and ST410 strains should be alert to prevent the spread of carbapenem-resistant genes within high-risk epidemic clones.

Keywords:

• carbapenemase-producing E. coli
• underlying diseases
• endoscopic retrograde cholangiopancreatography
• ERCP
• NDM

Data Sharing Statement

The data and material used to support the findings of this study are available from the corresponding author upon request.

Ethics Approval and Consent to Participate

The isolates used in this study were taken as part of a routine hospital procedure. All experimental protocols were approved by the research ethics committee of Hangzhou First People’s Hospital (ZN-20220331–0055–01).

Disclosure

Xiaojuan Qian and Weiwei Bao are co-first authors for this study. The authors have no conflicts of interest in this work.

Additional information

Funding

This work was supported by the Natural Science Foundation of Zhejiang Province (LQ20H200003, LZ22H190002), and the Medical and Health Technology Project of Hangzhou (A20210087).