Detection of plasmid-borne NDM-1 gene in clinical isolates of Enterobacteriaceae and their carbapenem antibiogram in cross river state, Nigeria

Abstract

Background: Carbapenemase-producing Enterobacteriaceae (CPE) are considered by the World Health Organization to be a critical global health concern. New Delhi Metallo-beta-lactamase (NDM) enzymes are capable of conferring resistance to almost all β-lactam antimicrobial drugs which are often considered drugs of last resort for the treatment of serious infections.

Aim: This study investigated the presence of blaNDM-1 gene on plasmids of multiple antibiotic resistant clinical isolates of Enterobacteriaceae in Cross River State, Nigeria.

Methodology: Seventy-nine Enterobacteriaceae which were obtained from urine and stool samples of patients in secondary and tertiary hospitals in Cross River State, Nigeria, were identified and tested for their susceptibility to three carbapenem antibiotics. Their ability to produce carbapenemase was determined by the Modified Hodges Test (MHT), re-modified Hodges Test (rMHT) and PCR.

Results: Two Klebsiella pneumoniae isolates from two separate urine samples obtained from two patients who had previously visited India, harboured the blaNDM-1 gene; both were resistant to the three carbapenems tested.

Conclusion: The detection of blaNDM-1 gene in Enterobacteriaceae confirms the circulation of the gene in Calabar. It further underscores the origin of the gene and its rapid spread. This has grave public health implications for Nigeria as India remains a major medical tourism destination for Nigerians.