Antibiotic Susceptibility Patterns of Pathogenic Bacteria Isolated from Patients Wound Swabs in Bingham University Teaching Hospital, Jos, Nigeria

Abstract

Background and Aim: Wound infections remain a significant cause of morbidity, prolonged hospitalisation and increased healthcare costs globally, particularly in developing countries including Nigeria. The emergence and rapid spread of antimicrobial resistance among wound pathogens has complicated empirical treatment, leading to treatment failures and poor clinical outcomes. The aim of this study was to determine the bacteriological profile and antibiotic susceptibility patterns of bacterial isolates from wound swabs of patients attending Bingham University Teaching Hospital, Jos, Nigeria. Place of Study: The study was conducted at Bingham University Teaching Hospital (BHUTH), Jos, Plateau State, Nigeria. Methodology: A hospital-based cross-sectional study was conducted among 232 patients with wound infections. Wound swabs were cultured on Blood agar, Chocolate agar, MacConkey agar and Mannitol Salt agar. Bacterial isolates were identified by cultural, morphological and biochemical tests. Antimicrobial susceptibility was determined by Kirby-Bauer disc diffusion against 12 antibiotics according to CLSI guidelines. Data were analysed using SPSS v20.0. Results: Out of 232 wound swabs, 80 bacterial isolates were recovered. Gram-positive Staphylococcus aureus was the predominant pathogen accounting for 44(55.0%) isolates, followed by Escherichia coli 17(21.3%), Pseudomonas aeruginosa 12 (15.0%), and Klebsiella pneumoniae 7(8.8%). Demographically, wound infections were highest in the 21–40-year age group (61.3%) and among males (68.8%). By wound type, trauma/accident wounds were the major source of S. aureus 22(50.0%), E. coli 11(64.7%) and K. pneumoniae 4(57.1%), while surgical-site infections accounted for 6(50.0%) of P. aeruginosa. By site, lower-limb wounds predominated across all species: S. aureus 61.4%, E. coli 64.7%, P. aeruginosa 75.0% and K. pneumoniae 85.7%. The antibiogram showed a high multidrug-resistant phenotype. Gram-negative isolates showed 100% resistance to cefotaxime, ceftriaxone, cefuroxime, cefixime, imipenem and nalidixic acid, with 82.4-94.1% resistance to ampicillin/cloxacillin, amoxicillin/clavulanate and ofloxacin. Similarly, S. aureus showed resistance to cefotaxime and cefixime (95.5% each), ceftriaxone and cefuroxime (93.2% each), erythromycin (88.6%) and amoxicillin/clavulanate (86.4%). Susceptibility was generally low, with levofloxacin showing the highest susceptibility of only 20.5% for S. aureus. Conclusion: This study identified Staphylococcus aureus as the leading cause of wound infection in Bingham University Teaching Hospital, Jos, predominantly associated with trauma and lower-limb wounds among young adult males. The emergence of high-level resistance to third-generation cephalosporins, β-lactam/β-lactamase inhibitors, fluoroquinolones and carbapenems among both Gram-positive and Gram-negative isolates severely limits empirical treatment options.