Prevalence and Antibiotic Resistance of Nasal Staphylococcus aureus in Hemodialysis Patients and Its Association with Catheter-Related Infections: A Retrospective Cohort Study

Background: Staphylococcus aureus nasal carriage is a significant risk factor for infections in hemodialysis patients. Objectives: This study aimed to investigate the prevalence of nasal S. aureus carriers, determine antibiotic resistance patterns, and assess the association with catheter-related infections in hemodialysis patients. Methods: This retrospective cohort study included 176 hemodialysis patients at Shahid Beheshti Hospital in Hamadan, Iran, from October 2022 to October 2023, who were selected via the census method. Nasal swabs were cultured, and S. aureus isolates underwent antibiotic susceptibility testing. Patient demographics, clinical data, and history of catheter-related infections were collected. Results: Of the 176 hemodialysis patients, 31 (17.5%) were nasal S. aureus carriers. Among these isolates, 64.6% were methicillin-sensitive S. aureus (MSSA), 16.1% were methicillin-resistant S. aureus (MRSA), and 19.3% showed inducible clindamycin resistance. The highest antibiotic sensitivity was to rifampin (90.3%), followed by cefotaxime and cefazolin (80.6% each). The highest resistance was to penicillin (87.1%) and amoxicillin (77.4%). A significant association was found between positive nasal cultures and the frequency of catheter-related bloodstream infections (P = 0.009). Conclusions: The prevalence of MRSA and antibiotic resistance in hemodialysis patients is concerning. Nasal S. aureus carriage was associated with an increased risk of recurrent catheter-related infections. Regular screening, decolonization, and updated empirical antibiotic selection and infection control measures may help reduce infection rates in this vulnerable population.