Antimicrobial resistance markers distribution in Staphylococcus aureus from Nsukka, Nigeria

• Published in: BMC infectious diseases 2024-03, Vol.24 (1), p.320-320, Article 320
• Main Authors: Agbo, Martina C, Ezeonu, Ifeoma M, Onodagu, Beatrice O, Ezeh, Chukwuemeka C, Ozioko, Chizoba A, Emencheta, Stephen C
• Format: Article
• Language: English
• Subjects: Acid resistance; Amoxicillin; Antibiotic resistance; Antibiotics; Antimicrobial agents; Antimicrobial resistance; Azithromycin; Cefoxitin; Ciprofloxacin; Clarithromycin; Clavulanic acid; Clinical isolates; Disease resistance; Distribution; Drug resistance; Drug resistance in microorganisms; Ertapenem; Erythromycin; Genes; Genetic testing; Laboratories; Mannitol; Markers; Methicillin; Multidrug resistance; Multidrug resistant organisms; Nucleotide sequence; Oxacillin; Pathogens; Polymerase chain reaction; Risk factors; S. Aureus; Staphylococcal infections; Staphylococcus aureus; Staphylococcus infections; Surveillance; Testing; Vancomycin
• ISSN: 1471-2334; 1471-2334
• DOI: 10.1186/s12879-024-09126-1

Multidrug resistance in Staphylococcus aureus continues to influence treatment complications in clinical settings globally. Multidrug-resistant-S. aureus (MDR-SA) is often genetically driven by resistance markers transferable in pathogenic strains. This study aimed to determine the distribution of resistance markers in clinical isolates of S. aureus in Nsukka, Nigeria. A total of 154 clinical samples were cultured on mannitol salt agar. Isolates were characterized using conventional cultural techniques and confirmed by PCR detection of S. aureus-specific nuc gene. Antibiotic resistance profiles of the isolates were determined against selected antibiotics using the disk-diffusion method, while screening for antibiotic resistance genes (Mec A, Erm A, Erm B, Erm C, Van A, and Van B) was by PCR. A total of 98 isolates were identified as S. aureus by conventional methods. Of these, 70 (71.43%) were confirmed by PCR. Phenotypically, the isolates exhibited high degrees of resistance to oxacillin (95.72%), erythromycin (81.63%), and ertapenem (78.57%) and 75.51% and 47.30% against methicillin and vancomycin, respectively. Multiple antibiotic resistance indexes of the isolates ranged from 0.3 to 1, and the most prevalent pattern of resistance was oxacillin-ertapenem-vancomycin-erythromycin-azithromycin-clarithromycin-ciprofloxacin- cefoxitin-amoxicillin-clavulanic acid. PCR screening confirmed the existence of various antibiotic resistance makers among the strains, with the most common resistance genes found in the isolates being Mec A (32.14%), Van A (21.43%), Van B (10.71%), Erm B (10.71%), and Erm C (17.86%). None possessed the Erm A gene. The study supports the need for necessary action, including rational drug use, continuous surveillance, and deployment of adequate preventive and curative policies and actions.