Bone and joint infections, etiology, empiric antimicrobial therapy (a 5-year study)

Abstract

Introduction: Osteomyelitis can cause serious disability and even lethality. Its treatment requires a combination of surgical and conservative methods. Antimicrobial therapy is often initiated before microbiological test results are available. Empirical regimens are then used, which are not universal because of variations in causative agents according to geographical region and time periods. The lack of up-to-date information on these issues in Bulgaria is the impetus for the present study.

Aim: The aim of this article is to conduct an epidemiological study and propose empirical antimicrobial therapy.

Patients and Methods: A total of 58 patients between 19 and 86 years of age, with a history of infection from 2 weeks to 30 years and different localization, admitted to the Department of Orthopaedics and Traumatology of the Lozenets University Hospital (2019–2024).

Results: Men were significantly more affected than women. The localization of the infection was predominantly in the tibia and hip region, and most rarely in the humerus and forearm bones. Among the comorbidities, the most prevalent were arterial hypertention, diabetes mellitus, and inferior paraplegia. S. aureus, Streptococcus agalactiae, and Enterococcus faecalis were mainly isolated from the osteomyelitis outbreak. S. aureus showed 100% susceptibility to vancomycin and 69% to moxifloxacin and rifampicin. Streptococcus agalactiae and Enterococcus faecalis were susceptible to a wide range of antibiotics, including vancomycin.

Conclusion: Vancomycin was the most widely used antimicrobial agent in the study group and must be included in empiric therapy. It is recommended to combine it with moxifloxacin covering the Gram (–) spectrum, and in patients with orthopaedic implants its use with rifampicin, an antibiotic with proven activity against bacterial biofilm formation, is desirable.