title: C-reactive protein is a useful predictor of metronidazole treatment failure in mild-to-moderate Clostridium difficile infection.
abstract: OBJECTIVE
  To assess the ability of C-reactive (CRP) protein, against the other commonly used metrics, to predict metronidazole treatment failure in Clostridium difficile infection.
  
  
  METHODS
  We retrospectively reviewed the case notes of 65 patients with C. difficile infection initially treated with metronidazole. Patients were grouped on the basis of outcome: those who responded to metronidazole within 6 days (cut-off as used by previous authors) versus those who required vancomycin. Individual predictor variables were examined between groups (using a t-test, Kruskal-Wallis test, or Fisher's exact test), and the strength of associations was assessed by logistic regression.
  
  
  RESULTS
  Of the 65 patients reviewed, 48 (74%) resolved with metronidazole alone. Regression analysis found that (CRP) white cell count and creatinine levels were significantly different across the metronidazole success/failure groups (P<0.01, P=0.01 and P=0.03, respectively).
  
  
  CONCLUSIONS
  (CRP) is a useful predictor of metronidazole treatment failure in mild-to-moderate C. difficile infection.
authors.affiliation: Queen Elizabeth Hospital, University of Bristol, Bristol, UK. hugo.farne@gmail.com
authors.forename: Hugo A
authors.initials: HA
authors.lastname: Farne
authors.forename: Natasha K
authors.initials: NK
authors.lastname: Martin
authors.forename: Janice
authors.initials: J
authors.lastname: Main
authors.forename: Timothy
authors.initials: T
authors.lastname: Orchard
authors.forename: Jonathan
authors.initials: J
authors.lastname: Tyrrell-Price
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000890:Anti-Infective Agents / Q000627:therapeutic use*; D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000032:analysis*; D016360:Clostridioides difficile / Q000187:drug effects* / Q000302:isolation & purification; D003015:Clostridium Infections / Q000097:blood / Q000175:diagnosis / Q000188:drug therapy* / Q000382:microbiology; D003404:Creatinine / Q000097:blood; D057915:Drug Substitution; D005260:Female; D006801:Humans; D007958:Leukocyte Count; D016015:Logistic Models; D008297:Male; D008795:Metronidazole / Q000627:therapeutic use*; D008875:Middle Aged; D016017:Odds Ratio; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012720:Severity of Illness Index; D013997:Time Factors; D017211:Treatment Failure; D014640:Vancomycin / Q000627:therapeutic use
chemical_list: D000890:Anti-Infective Agents; D015415:Biomarkers; D008795:Metronidazole; D014640:Vancomycin; D002097:C-Reactive Protein; D003404:Creatinine