Prevalence of <i>Stenotrophomonas maltophilia</i> colonization among patients receiving mechanical ventilation in long-term care facilities in Maryland, United States

There is increasing concern regarding the importance of <i>Stenotrophomonas maltophilia</i> as a nosocomial infection, given its inherent antibiotic resistance, particularly for patients who have risk factors such as being mechanically ventilated. The prevalence of colonization receiving mechanical ventilation in chronic care facilities has not been studied. The Multi-Drug-Resistant Organism (MDRO) Prevention Collaborative performed a point prevalence of patients receiving mechanical ventilation in all 18 chronic care facilities in Maryland between 7 March 2023 and 8 June 2023. Patients had at least one sputum, skin, or perianal surveillance culture collected (579 samples). Samples were tested using three microbiological methods: (i) growth on Acinetobacter CHROMagar, (ii) growth on MacConkey agar with an imipenem disk, and (iii) growth in brain-heart infusion broth with an imipenem disk, followed by growth on MacConkey agar. 21.4% (124/579) of the samples collected grew <i>S. maltophilia</i>. Among 200 patients, 58.5% had at least one positive site (117/200). <i>S. maltophilia</i> was isolated from 58.2% (113/194) of sputum, 4.1% (8/193) of skin, and 1.6% (3/185) of perianal samples. Two patients had multiple samples that grew <i>S. maltophilia</i> for a total of 119 positive samples from 117 patients. Mechanically ventilated patients in chronic care facilities may be at risk of <i>S. maltophilia</i> colonization and potential infection.IMPORTANCEThere is increasing concern regarding the importance of <i>Stenotrophomonas maltophilia</i> as a nosocomial infection, given its inherent antibiotic resistance. <i>S. maltophilia</i> is widely present in the environment, and while not always virulent, it has been documented to have high morbidity and mortality among certain at-risk patient populations. We analyzed mechanically ventilated patients in chronic care facilities in the state of Maryland to quantify the burden of <i>S. maltophilia</i> in this population. More than half of patients receiving mechanical ventilation in chronic care facilities were colonized with <i>S. maltophilia,</i> which was most frequently isolated from sputum samples.