TABLE 1

Performance of 30 rectal swabs with liquid medium in the detection of Clostridium difficile compared to performance of stool samples

Result of C. difficile detection in FS by assayaResult of C. difficile detection in stool sample (no.)Detection of C. difficile using FS compared with stool samples (% [95% CI])b
PositiveNegativeSensitivitySpecificityPPVNPV
GX83.3 (64.5–93.7)100 (83.4–100)
    Positive250
    Negative50
Toxigenic culture85.7 (62.6–96.2)66.7 (30.9–91)85.7 (62.6–96.2)66.7 (30.9–91)
    Positive183
    Negative36
GDH (by CDQCC)88 (67.7–96.8)100 (46.3–100)100 (81.5–100)62.5 (25.9–89.8)
    Positive220
    Negative35
Toxin A/B (by CDQCC)68.8 (41.5–87.9)100 (73.2–100)100 (67.9–100)73.7 (48.6–89.9)
    Positive110
    Negative514
  • a FS, rectal swab with liquid medium; GX, GeneXpert C. difficile/Epi test; CDQCC, C. Diff Quik Chek Complete.

  • b CI, confidence interval; PPV, positive predictive value; NPV, negative predictive value.