Clinical outcomes and risk factors associated with Stenotrophomonas maltophilia infections: A comprehensive study

Background: Stenotrophomonas maltophilia is an environmental organism which is intrinsically multidrug resistant and causes infection in immunocompromised patients. Aim and Objectives: To evaluate the rate of isolation of S. maltophilia, antibiotic resistance profile, risk factors, and clinical outcome. Material and Methods: It was a retrospective study wherein clinical and laboratory data related to various clinical samples which yielded S. maltophilia in 2½ year period were included. Risk factors and clinical outcomes were analysed. Results: Maximum isolation rate of S. maltophilia was from respiratory samples 52/80 (65%), 78 (97.5%) were sensitive to ofloxacin; 76 (95%) levofloxacin; 75 (93.8%) chloramphenicol; 73 (91.2%) tigecycline; 61(76.2%) ticarcillin clavulanic acid and 60 (75%) were sensitive to trimethoprim-sulfamethoxazole (TMP/SMX). Of the 45 patients whose clinical history could be obtained, 13 (28.9%) patients expired. Of these 3 (23%) were cancer patients, 1 (7.6%) was a kidney transplant patient, 3 (23%) had chronic kidney disease, 3 (23%) had brain damage due to an accident, 2 (15.3%) had septic shock and one was COVID 19 patient. Conclusions: Mortality of the patients was associated with longer period of stay in the hospital. Of the 80 S. maltophilia isolates approximately 96% were sensitive to fluoroquinolones and 75% were sensitive to TMP/SMX. Further studies with larger sample sizes or prospective designs are needed for stronger evidence.