Antibiotic Resistance in Citrobacter, Isolated in Elderly Patients with Urinary Tract Infections in the Abidjan District, Ivory Coast
Eric Joël Tahou *
Department of Biosciences, Laboratory of Biotechnology, Agriculture, and Valorization of Biological Resources, Félix Houphouët-Boigny University, 22 BP 582 Abidjan 22, Côte d’Ivoire.
Bernardin Ahouty Ahouty
Jean Lorougnon Guédé University, BP 150 Daloa, Côte d’Ivoire.
Germain Droh
Department of Biosciences, Laboratory of Biotechnology, Agriculture, and Valorization of Biological Resources, Félix Houphouët-Boigny University, 22 BP 582 Abidjan 22, Côte d’Ivoire.
Assanvo Simon-Pierre N’guetta
Department of Biosciences, Laboratory of Biotechnology, Agriculture, and Valorization of Biological Resources, Félix Houphouët-Boigny University, 22 BP 582 Abidjan 22, Côte d’Ivoire.
*Author to whom correspondence should be addressed.
Abstract
Background: Urinary tract infections are common among older adults, and the emergence of antibiotic-resistant Citrobacter spp. complicates therapeutic management.
Aims: The objective of this study was to characterise antibiotic resistance genes in Citrobacter isolates from elderly patients presenting with urinary tract infections.
Study Design: This was a retrospective study.
Place and Duration of Study: The study was conducted at the Bacteriology and Virology Laboratory of the Pasteur Institute, Abidjan, Ivory Coast, from February 2023 to March 2024.
Methodology: A retrospective study was conducted using 47 clinical Citrobacter isolates collected at the Institut Pasteur de Côte d’Ivoire. Antimicrobial susceptibility was assessed by disc diffusion, extended-spectrum β-lactamase production was evaluated using a double-disc synergy test, and polymerase chain reaction was used to detect blaTEM, blaSHV, and blaCTX-M-1 genes.
Results: Citrobacter strains were isolated from 59.57% of the urine samples. Two species of Citrobacter were identified: Citrobacter freundii 85% (40/47) and Citrobacter koseri 15% (7/47). Generally, a low resistance rate (10.71%) was observed among the Citrobacter isolates in the presence of kanamycin. However, they exhibited a high resistance rate of 89.36% (42/47) to cefixime. Except for amikacin and kanamycin, the susceptibility profile of Citrobacter freundii showed resistance rates of 100% to both cefixime and aztreonam. Regarding Citrobacter koseri, a high resistance rate of 87.5% (35/40) was observed for cefixime, whereas a low resistance rate of 10.63% (5/47) was observed for kanamycin. In this study, the prevalence of Citrobacter strains producing extended-spectrum β-lactamases (ESBL) was 78.72% (37/47). Among the 47 strains, 14.9% (7/47) harbored the blaCTX-M-1 gene, 12.77% (6/47) carried the blaTEM gene, and 4.26% (2/47) possessed the blaSHV gene.
Conclusion: The high resistance rates obtained compromise treatment efficacy. Consequently, there is an urgent need to implement surveillance strategies and develop new therapeutic alternatives to address this growing public health threat.
Keywords: Antimicrobial resistance, Citrobacter koseri, Citrobacter freundii, urinary tract infection, elderly patients, extended-spectrum β-lactamase, β-lactam resistance, blaCTX-M-1, blaTEM, blaSHV