title: In recurrent C. difficile, the CRP response to the primary C. difficile infection predicts whether the same strain or a different strain will cause a second infection.
abstract: BACKGROUND
  Clostridium difficile is the leading cause of antibiotic-associated diarrhoea and is associated with an increase in morbidity and mortality. There is a wide variance in disease severity with some patients suffering a single, self-limiting episode of diarrhoea while others suffer more intractable problems with recurrent attacks or toxic dilatation. Numerous different C. difficile ribotypes exist, some of which are considered hypervirulent. The magnitude of toxin production alone is not sufficient to explain the varying virulence of these ribotypes, suggesting the involvement of other mechanisms.
  
  
  METHODS
  To test the same patient's response to infection with different C. difficile ribotypes, we reviewed 45 patients who suffered two episodes of C. difficile infection and determined by ribotyping and MLVA whether the second episode was due to the same strain or a different strain.
  
  
  RESULTS
  Patients harbouring a different strain had significantly higher C-reactive protein (CRP) responses on the first assessed infection (143 mg/L ± 20 vs. 55 ± 9.63, p = 0.0001) and a significantly lower CRP on reinfection (p = 0.048). Same strain patients had a non-significant increase in CRP response on second infection.
  
  
  CONCLUSIONS
  This suggests that the inflammatory response to C. difficile is determined by an interaction between host immunobiology, previous exposure and C. difficile strain.
authors.affiliation: Department of Medicine, Imperial College London, London, W12 0NN, UK.
authors.forename: Kangni
authors.initials: K
authors.lastname: Chen
authors.forename: Stephanie
authors.initials: S
authors.lastname: d'Arc
authors.forename: Naveen
authors.initials: N
authors.lastname: Setty
authors.forename: Kathy
authors.initials: K
authors.lastname: Bamford
authors.forename: Neil
authors.initials: N
authors.lastname: Fairweather
authors.forename: Jonathan
authors.initials: J
authors.lastname: Tyrrell-Price
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000378:metabolism*; D016360:Clostridioides difficile / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D015331:Cohort Studies; D004269:DNA, Bacterial / Q000032:analysis; D004761:Enterocolitis, Pseudomembranous / Q000097:blood / Q000382:microbiology*; D005260:Female; D006801:Humans; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D018598:Minisatellite Repeats; D016133:Polymerase Chain Reaction; D012008:Recurrence; D012189:Retrospective Studies; D021521:Ribotyping
chemical_list: D015415:Biomarkers; D004269:DNA, Bacterial; D002097:C-Reactive Protein