Rapid and accurate eXDR screening: use Xpert Carba-R® with FecalSwab®

Diagn Microbiol Infect Dis. 2021 Apr;99(4):115279. doi: 10.1016/j.diagmicrobio.2020.115279. Epub 2020 Nov 26.


The FecalSwab® displays high performances for stool culture, but it was not assessed for carbapenemase-producing Enterobacterales (CPE) screening. We assess the performances of the Xpert Carba-R v2® with the FecalSwab®. Using a collection of 12 CPE strains, the limit of detection was assessed at 158 CFU/swab [interquartile range 93-589]. In 2019, 1540 swabs were included by 4 hospital laboratories, of which 39 (2.5%) yield an invalid result. Among the 1501 valid, 87 (5.8%) were positives by culture and PCR and 25 (1.7%) were discrepant: 7 PCR-negative culture-positive, and 18 PCR-positive culture-negative. Two PCR-positive culture-negative results involved non-Enterobacterales strains: a KPC-producing Acinetobacter baumannii and a KPC-producing Aeromonas spp. The overall percent agreement was 98.3% and the Kappa value was 0.88. FecalSwab® is an accurate sampling device for CPE screening. It allows performing all eXDR screening using a single swab, simplifying the sample collection, and improving the patient comfort. Regarding discrepant, we suggest combining a CPE screening by both culture and Xpert Carba-R v2® methods.

Keywords: Carbapenemase-producing Enterobacterales (CPE); EXDR; FecalSwab; Outbreak; Vancomycin-resistant Enterococcus (VRE); Xpert Carba; Xpert vanA/vanB.

MeSH terms

  • Bacterial Proteins / metabolism
  • Bacteriological Techniques / methods
  • Carbapenem-Resistant Enterobacteriaceae / isolation & purification*
  • Drug Resistance, Bacterial*
  • Enterobacteriaceae Infections / diagnosis*
  • Enterococcus / drug effects
  • Feces / microbiology*
  • Humans
  • Molecular Diagnostic Techniques / methods
  • Sensitivity and Specificity
  • Vancomycin / pharmacology
  • X-Ray Diffraction
  • beta-Lactamases / metabolism


  • Bacterial Proteins
  • Vancomycin
  • beta-Lactamases
  • carbapenemase