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Aims In Tunisia, limited research has focused on characterizing clinical vancomycin-resistant Enterococcus faecium (VREfm). This study aimed to bridge this knowledge gap by molecular characterization of antimicrobial resistance, determining the genetic elements mediating vancomycin-resistance, and whole-genome sequencing of one representative VREfm isolate Methods and results Over 6 years (2011–2016), a total of eighty VREfm isolates responsible for infection or colonization were identified from hospitalized patients, with the incidence rate increasing from 2% in 2011 to 27% in 2016. All of these strains harbored the vanA gene. The screening for antimicrobial resistance genes revealed the predominance of ermB, tetM , and aac(6′)-Ie-aph(2′')-Ia genes and 81.2% of strains harbored the Tn 1545. Pulsed-field gel electrophoresis identified seven clusters, with two major clusters (belonging to ST117 and ST80) persisting throughout the study period. Seven Tn 1546 types were detected, with type VI (truncated transposon) being the most prevalent (57.5%). Whole-genome sequencing revealed a 3 028 373 bp chromosome and five plasmids. Mobile genetic elements and a type I CRISPR-cas locus were identified. Notably, the vanA gene was carried by the classic Tn 1546 transposon with ISL3 insertion on a rep17pRUM plasmid. Conclusion A concerning trend in the prevalence of VREfm essentially attributed to CC17 persistence and to horizontal transfer of multiple genetic variants of truncated vanA -Tn 1546. [ABSTRACT FROM AUTHOR]

Simple Summary: The research aims to evaluate the diagnostic performance of low-dose chest CT (LDCCT) in detecting pulmonary infections in neutropenic patients with hematologic malignancies. Driven by concerns over radiation exposure in high-risk patients undergoing standard chest CT scans (SDCCT), the research investigates whether LDCCT, with reduced radiation and noise reduction algorithms, matches SDCCT in image quality and diagnostic accuracy. Involving 164 neutropenic patients with 256 CT exams, the study scrutinizes specific radiological criteria linked to pulmonary infections. The researchers analyzed objective parameters (such as image noise and attenuation levels), subjective evaluations (image quality, noise, and artifacts), and diagnostic performance. The findings reveal a 47% reduction in radiation dose with LDCCT but a lower diagnostic performance, especially in detecting consolidation and ground glass opacities. The authors caution against relying solely on LDCCT for initial assessments in patients with hematologic malignancies, emphasizing the importance of further research to optimize diagnostic protocols. The study aimed to assess the image quality and diagnostic performance of low-dose Chest Computed Tomography (LDCCT) in detecting pulmonary infections in patients with hematologic malignancies. A total of 164 neutropenic patients underwent 256 consecutive CT examinations, comparing 149 LDCCT and 107 Standard-Dose Chest CT (SDCCT) between May 2015 and June 2019. LDCCT demonstrated a 47% reduction in radiation dose while maintaining acceptable image noise and quality compared to SDCCT. However, LDCCT exhibited lower sensitivity in detecting consolidation (27.5%) and ground glass opacity (64.4%) compared to SDCCT (45.8% and 82.2%, respectively) with all the respective p-values from unadjusted and adjusted for sex, age, and BMI analyses being lower than 0.006 and the corresponding Odds Ratios of detection ranging from 0.30 to 0.34. Similar trends were observed for nodules ≥3 mm and ground glass halo in nodules but were not affected by sex, age and BMI. No significant differences were found for cavitation in nodules, diffuse interlobular septal thickening, pleural effusion, pericardial effusion, and lymphadenopathy. In conclusion, LDCCT achieved substantial dose reduction with satisfactory image quality but showed limitations in detecting specific radiologic findings associated with pulmonary infections in neutropenic patients compared to SDCCT. [ABSTRACT FROM AUTHOR]