Molecular Detection of BlaSHV and Sul2 Genes in Multidrug-Resistant Shigella flexneri from Clinical Specimens in North-East Nigeria

Abstract

The continued detection and dissemination of multidrug-resistant (MDR) Shigella species pose a significant public health threat worldwide, especially in resource-limited regions such as the Northeast, Nigeria. Extended-Spectrum Beta-Lactamases (ESBLs) encoded by genes including BlaSHV confer resistance to critical Beta-lactam antibiotics, and sulfonamide resistance genes such as sul2 complicate therapeutic regimens by mediating resistance to widely used drugs. The available data on ESBL and sulfonamide genes producing Shigella from African countries reflects limited technical resources, the absence of a national or regional surveillance system, and the lack of required publications for the limited data generated. This Study reports the genotypic detection confirming BlaSHV and Sul2 resistance genes from multidrug-resistant Shigella Flexneri isolates from clinical specimens in Yobe State Specialist Hospital, Damaturu. The identified MDR phenotype Shigella species were collected, and their DNA was extracted and amplified using multiplex and simple PCR with various primer sets targeting specific sequences of the resistance genes. The gel images were then taken. Among five MDR Shigella strains tested by multiplex PCR against three β-lactamases (BlaTEM, BlaCTX-M, and BlaSHV), BlaSHV was detected in a Shigella flexneri strain. In this Study, no blaTEM and blaCTX-M genes were detected in any of the five products. In addition, two isolates (all Shigella flexneri strains) were found to harbor Sul2 genes, while only one MDR Shigella flexneri isolate harbored both BlaSHV and Sul2 resistance genes, unlike the potential XDR Shigella flexneri, which carries only the Sul2 resistance gene. MDR Shigella flexneri strains isolated from Specialist Hospital, Damaturu, Yobe State, are a reservoir of disseminatable BlaSHV and Sul2 resistance genes. However, despite its limitations, this Study highlights the urgent need for enhanced molecular antimicrobial stewardship and targeted interventions to curb the spread of resistant Shigella clones in this vulnerable region.