Microbiological Profile and Drug Resistance in Bone and Joint Infections: A Survey in Orthopedic Wards of a Great Referral Hospital in Tehran, Iran

Background: Patients undergoing orthopedic surgery are at risk of nosocomial infections, and antibiotic resistance is known to increase the risk of such infections. Objectives: We aimed to determine the rate of antibiotic resistance in patients admitted to orthopedic wards in one of the largest referral hospitals in Iran. We also ascertained responsible antibiotic-resistant microorganisms in patients with bone and joint infections. Methods: The present cross-sectional investigation was concluded over a period of five years, from March 2018 to March 2022, at a great referral hospital in Tehran. Laboratory data, including the organisms isolated and their antibiotic resistance patterns, were collected by reviewing the hospital information system. Results: In total, 2650 specimens obtained from patients with suspected bacterial infections were transferred to the hospital’s laboratory, 880 (33.2%) of which were positive for bacterial infections. The maximum antibiotic resistance rate against an antibiotic was observed to be 58% for Staphylococcus aureus (erythromycin), 75% for Klebsiella pneumonia (ampicillin/sulbactam), 64.5% for Escherichia coli (imipenem), 76.2% for coagulase-negative Staphylococcus (vancomycin), 100% for Acinetobacter baumannii (imipenem), 52% for S. epidermidis (erythromycin), 85.9% for Enterobacter species (gentamycin), and 65.6% for Pseudomonas aeruginosa (ampicillin/sulbactam). The overall rate of multi-drug resistance was obtained as 27.6%. Conclusions: A high rate of resistance of various bacterial strains to common antibiotics, especially erythromycin, ampicillin, imipenem, vancomycin, and gentamycin, was denoted in orthopedic wards. Also, a high rate of multi-antibiotic resistance was encountered in these wards, where more than a quarter of the bacterial strains showed such resistance.