Septic arthritis of the knee joint in Azerbaijan: a 5-year retrospective microbiological investigation

Background: Musculoskeletal infections, particularly septic arthritis of the knee, present significant diagnostic and therapeutic challenges in orthopedic surgery. While the global burden is well-documented, there is a paucity of microbiological data regarding native joint infections in specific regions such as Azerbaijan, which complicates the selection of appropriate empiric antimicrobial therapy.

Objective: This study aims to characterize the microbiological profile, clinical presentation, and antibiotic susceptibility patterns of knee septic arthritis in a cohort of patients treated at a tertiary referral center in Baku, Azerbaijan.

Key Points: A retrospective analysis of 54 patients (mean age 43.8 years) treated between 2014 and 2019 was conducted. Etiological factors included intra-articular steroid injections in 25.9% of cases and prior surgery in 9.3%. Cultures were positive in 79.6% of patients, with polymicrobial infections identified in 72.1% of those with positive results. Staphylococcus aureus was the most prevalent isolate (29.1%), followed by Candida albicans (24.4%) and Staphylococcus epidermidis (16.3%). Patients with bone involvement (septic osteoarthritis) exclusively exhibited mixed microflora. Surgical intervention was associated with a higher incidence of polymicrobial infections (83.7%) compared to conservative management (16.3%). Antimicrobial testing revealed high susceptibility to carbapenems, while resistance to aminoglycosides and the presence of vancomycin-intermediate Staphylococci were noted.

Conclusion: Septic arthritis of the knee in this region is frequently polymicrobial and often associated with prior medical interventions. The high prevalence of mixed flora and specific resistance patterns necessitate comprehensive microbiological screening to guide targeted antibiotic therapy and improve clinical outcomes in complex joint infections.