Isolation and Characterization ofStenotrophomonas maltophiliaIsolates from a Brazilian Hospital

Abstract

Stenotrophomonas maltophilia is an emerging nosocomial pathogen responsible for several infections in immunocompromised patients. To characterize the antimicrobial resistance and virulence potential of this microorganism in a Brazilian hospital, a total of 936 samples were collected from a nosocomial environment and medical devices, and 100 isolates from clinical specimens were obtained in the same hospital. S. maltophilia was found in 3% of the samples collected, especially in bed rails from hospital rooms. The smf-1 gene was detected in 23% and 42% of the clinical and hospital environment isolates, respectively, and almost all (96.8%) isolates that harbored smf-1 were able to form biofilm. All isolates were susceptible to minocycline and chloramphenicol, and the majority of isolates were susceptible to levofloxacin. High resistance to ceftazidime was detected in both groups of isolates. Resistance to trimethoprim-sulfamethoxazole (TMP/SMX) was found in 14.8% of the isolates. All TMP/SMX-resistant isolates presented class 1 integron and sul1 gene, and 47.4% of them also harbored the sul2 gene, which was inserted into a 7.3 kb plasmid. Genetic relatedness among the isolates was evaluated by enterobacterial repetitive intergenic consensus-PCR, and eight genetic patterns were identified. One pattern comprised 54.7% of isolates and was spread among clinical and environmental (furniture and medical devices) sources. The presence of S. maltophilia in the hospital environment indicates that it can act as a reservoir of this microorganism. In addition, hospital isolates resistant to TMP/SMX showed that the genetic determinants were present in mobile elements, which can constitute great concern, as it may indicate a tendency to spread.

Intra‐hospital dissemination of clinical and environmental isolates of Stenotrophomonas maltophilia from Tehran

“…This finding may point the potential patient-bed-patient transmission. Genetic relatedness of clinical and environmental isolates of S. maltophilia was examined using ERIC-PCR by Gallo et al and they found five patterns in both sources (Gallo et al 2016). Also, common PTs of S. maltophilia between environmental and lavage specimens were identified by Ahn et al (2007) in Korea.…”

Achromobacter xylosoxidans and Stenotrophomonas maltophilia: Emerging Pathogens Well-Armed for Life in the Cystic Fibrosis Patients’ Lung

“…After adhesion, the ability to invade CF-derived IB3-1 bronchial epithelial cells was reported for Sm only, to date [ 81 ], and it represents a way to persist in the CF airways, as intracellular bacteria represent a less accessible reservoir of pathogens for both immune system and antimicrobial agents. Genes, such as the smf -1 gene coding for the fimbrial protein Smf-1, have a crucial role in the bacterial adhesion [ 82 ] and further biofilm formation as only Sm isolates containing the smf -1 gene were found to produce biofilm [ 83 ] ( Figure 1 ). These observations are important for the initial CF patient airway colonization by Axc and Sm via adhesion to the surface of airway mucosae.…”

Antibiotic Resistance Surveillance of Clinical Isolates of Stenotrophomonas maltophilia Strains in the Central South of China from 2016 to 2019

“…In the earlier study, clinical isolates from S. maltophilia have been mainly isolated from sputum samples (56.2% of all isolates) (11). Similarly, Gallo SW et al proclaimed that this pathogen was chiefly separated from tracheal aspirate (55%), blood (15.0%) and sputum (14.0%) samples from a Brazilian Hospital (22). However, Kaur et al reported that maximal numbers of strains from blood (61.32%) samples along with respiratory samples (26.41%) (23).…”