Molecular Analysis of Tigecycline Resistance in Carbapenem-Resistant Enterobacterales (Cre) in Mthatha and Surrounding Hospitals

Background: The emergency of carbapenem-resistant Enterobacterales is prevalent and poses a significant threat to health systems worldwide. This study aimed to conduct a molecular analysis of tigecycline resistance in 100 CRE in hospital isolates from Mthatha and surrounding hospitals. Methods: A retrospective study among patients who attended Nelson Mandela Academic Hospital (NMAH) and Mthatha Regional Hospital (MRH), Eastern Cape, South Africa. Enterobacterales isolates were identified using the Vitek2® system (bioMérieux), E-test was performed in 100 CRE hospital isolates according to manufacturer’s instructions, A multiplex SYBR green-based PCR assay for rapid detection of tet(X) and its variants, including tet(X1), tet(X2), and high-level tigecycline resistance genes tet(X3), tet(X4), and tet(X5) were developed. Results: The results show a notable high prevalence of CRE infections in neonatal, male surgical, and maternal and pediatric wards, predominantly driven by Klebsiella spp. (53.4%), followed by Enterobacter spp. (20.5 %), then Escherichia coli (6.7%), 7.2% of CRE were resistant to Tigecycline (E-TEST), Tet(X) genes were Not responsible for tigecycline resistance in this setting. The risk factors associated with tigecycline resistance in CRE include age, pre-exposure to antibiotics, prolonged hospitalization, and undergoing invasive procedures indicated by strong r2 =0.9501. Conclusion: CRE gradually evolves, posing a significant threat to patients of all ages; early detection of carbapenemase production in clinical infections, carriage states, or both is essential to prevent hospital-based outbreaks.