Bacterial Isolates From Orthopedic Posttraumatic Surgical Infections in Northern Ghana: ESβL Detection and Analysis of Antimicrobial Resistance Trends.

Abstract

Background: Surgical site infections (SSIs) remain a critical challenge globally and are aggravated by rising antimicrobial resistance (AMR). Here, we evaluated the bacterial profile, AMR patterns, and ESβL characterization of isolates from patients diagnosed with SSI after trauma orthopedic surgery. Methods: This prospective study was carried out at Tamale Teaching Hospital from September 2023 to May 2024. Patients were asked to provide demographic data. Samples were also collected from patients suspected of SSI and cultured for bacterial isolation, identification, and AMR characterization. Results: In all, 210 patients were recruited for this study, and 14 (6.7%) out of 19 suspected cases developed SSI. Of 19 specimens, 14 (73.68%) were culture-positive, yielding 22 isolates. Monomicrobial growth were 7 (50.0%) and polymicrobial growth 7 (50.0%). Among the isolates, 3 (13.64%) were Gram-positive and 19 (86.36%) were Gram-negative bacilli. Pseudomonas aeruginosa (5, 22.73%) were the most common isolates, followed by Klebsiella spp. (4, 18.18%). ESβL-positive isolates were 3 (23.08%). PCR confirmed the expression of CTXM and SHV genes by two Klebsiella spp. and the CTXM gene by Proteus vulgaris. Conclusion: Gram-negative bacteria, particularly Pseudomonas aeruginosa, were the dominant isolates from surgical sites after trauma orthopedic surgery. Among the Gram-positives, Staphylococcus aureus was dominant. Among the Enterobacterales isolates, ESBL production was detected in three cases (23.08%), with two Klebsiella spp. harboring CTXM and SHV resistance genes, and CTXM in one Proteus vulgaris. The current study has revealed varied resistant patterns of AMR, with CTXM and SHV as common ESβL genes among the isolates. The clinical identification of CTX-M and SHV genes could guide clinicians to consider alternative treatments to optimize therapeutic outcomes and limit the spread of resistant pathogens.