Antibiotic resistance and prevalence of Stenotrophomonas maltophilia isolated from clinical samples.

Abstract

Background: Stenotrophomonas maltophilia is an emerging non-fermenting Gram-negative bacillus increasingly implicated in healthcare-associated infections. Its remarkable ability to form biofilms on inert surfaces and invasive medical devices, together with its intrinsic and acquired resistance mechanisms, makes it a major therapeutic challenge in hospital settings. Objective: This study aimed to describe the epidemiological characteristics and antimicrobial susceptibility profile of Stenotrophomonas maltophilia isolates recovered in our microbiology laboratory. Methods: A retrospective study was conducted on clinical isolates of S. maltophilia obtained from various clinical specimens. The bacterial exam was performed according to standard microbiological guidelines. Results: Over the study period, the prevalence of Stenotrophomonas maltophilia isolates was 0.25% among all bacterial isolates (34 out of 13,959). Respiratory specimens were the most frequent source (23.53%, n = 8), followed by blood cultures (17.65%, n = 6). Most isolates originated from intensive care units (47.06%, n = 16). Trimethoprim–sulfamethoxazole retained high efficacy with a susceptibility of 81.48%, while Minocycline demonstrated the highest activity, with a susceptibility rate of 100%. In contrast, the high resistance rates were observed for ceftazidime (61.90%). Conclusion: Stenotrophomonas maltophilia represents an emerging nosocomial pathogen with significant therapeutic implications. Continuous monitoring of local resistance profiles, along with strengthened infection prevention measures and appropriate antibiotic use, is essential to limit the spread of resistant strains.