Prevalence and antibiotic resistance of Stenotrophomonas maltophilia in the Republic of Belarus in 2020–2024

Objective. To assess the prevalence and antibiotic resistance of S. maltophilia in Belarus over a five – year period (2020–2024).
Materials and methods. A retrospective analysis of microbiological surveillance data (WHONET) was performed on clinical S. maltophilia isolates obtained from patients in six regions of Belarus and Minsk city. A total of 3267 isolates were included. Antimicrobial susceptibility was determined by disk diffusion or automated systems and interpreted according to CLSI criteria. Statistical analysis included calculation of 95 % confidence intervals (Clopper – Pearson method), comparison of proportions and trend assessment.
Results. The largest numbers of isolates were recovered from Minsk city (56.1 %), Minsk region (13.3 %), Mogilev region (13.0 %) and Gomel region (8.2 %). Resistance to trimethoprim/sulfamethoxazole was 32.5 % (95 % CI (30.6–34.3 %)), susceptibility – 48.9 %. Sharp interregional differences were observed: resistance ranged from 7.4 % in Mogilev region to 95.7 % in Grodno region. Susceptibility to levofloxacin was high (81.7 %), with a trend of decreasing resistance from 24.7 % in 2021 to 5.7 % in 2024 (p < 0.001). High resistance rates to ceftazidime (80.1 %) and ticarcillin/clavulanate (24.6 %) confirmed intrinsic β-lactamase-mediated resistance. According to preliminary data (n = 43), minocycline showed high activity (88.4 % of susceptible isolates).
Conclusion. Significant interregional differences in S. maltophilia resistance to trimethoprim/sulfamethoxazole and fluoroquinolones were found in Belarus. A marked positive trend of restoration of susceptibility to levofloxacin was observed. These findings support the need for continuous epidemiological surveillance and a region tailored approach to empirical therapy of S. maltophilia infections.

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