Is Fecal Leukocyte Test a good predictor of Clostridium difficile associated diarrhea?

Ann Clin Microbiol Antimicrob. 2006 Apr 19;5:9. doi: 10.1186/1476-0711-5-9.


Background: Fecal leukocyte test (FLT) is widely used to screen for invasive diarrheas including C. difficile associated diarrhea (CDAD), which account for more than 25 % of all antibiotic associated diarrhea.

Method: 263 stool samples from patients with suspected CDAD were studied simultaneously for fecal leukocyte test (FLT) and Clostridium difficile toxin assay (CDTA). FLT was performed by the Giemsa technique and CDTA was performed by enzyme immuno assay (EIA).

Results: Sensitivity, specificity, positive predictive value and negative predictive value of FLT as compared to CDTA were 30%, 74.9%, 13.2% and 89.3% respectively.

Conclusion: Considering the poor sensitivity of FLT, and the comparable cost and time of obtaining a CDTA at our institution, we conclude that FLT is not a good screening test for CDAD. Possible reasons for FLT being a poor predictor of CDTA are discussed.

MeSH terms

  • Bacterial Proteins / analysis*
  • Bacterial Toxins / analysis*
  • Diarrhea / diagnosis*
  • Enterocolitis, Pseudomembranous / diagnosis*
  • Enterotoxins / analysis*
  • Feces / cytology*
  • Humans
  • Leukocytes*
  • Retrospective Studies


  • Bacterial Proteins
  • Bacterial Toxins
  • Enterotoxins
  • tcdA protein, Clostridium difficile
  • toxB protein, Clostridium difficile