title: Similar outcomes of IBD inpatients with Clostridium difficile infection detected by ELISA or PCR assay.
abstract: BACKGROUND
  Clostridium difficile infection (CDI) is known as a risk factor for exacerbation of inflammatory bowel disease (IBD). CDI has been most commonly tested with enzyme-linked immunosorbent assay for toxins, but with a suboptimal sensitivity. Compared with conventional ELISA, the polymerase chain reaction-based assay (PCR) is a highly sensitive detection technique for C. difficile. However, its pure detection of only the DNA of toxin B may lead to over-treatment.
  
  
  OBJECTIVE
  The purpose of this study was to compare the frequency and clinical outcomes of IBD inpatients with CDI between the PCR and ELISA assays and to assess the factors associated with CDI.
  
  
  METHODS
  The retrospective study was performed with the IBD inpatients at Cleveland Clinic from 2009 to 2011, who were tested by either ELISA or PCR or both. Outcomes under comparison included intensive care unit transfer, length of hospital stay, requirement for gastrointestinal surgeries and all cause re-hospitalization. Multivariable analysis was performed to assess the associated factors for the combined cohorts.
  
  
  RESULTS
  A total of 255 patients were included, among them 222 had ELISA test, and 103 had PCR test. Thirteen (5.9 %) patients were ELISA positive, versus 14 (13.5 %) patients who were PCR positive (P = 0.02). With comparable demographic and clinical background, clinical outcomes of the ELISA and PCR positive groups showed no significant difference. Instead, the overall percentage of C. difficile positive patients had a much higher rehospitalization rate than C. difficile negative patients (P < 0.01). Multivariable analysis identified comorbidities (P = 0.03), extra-intestinal manifestations (P = 0.03) and PPI use (P < 0.01) as the associated factors for CDI.
  
  
  CONCLUSIONS
  There was a greater percentage of patients tested positive by PCR compared to ELISA. The outcomes of CDI diagnosed by PCR or ELISA, however, appeared comparable. The presence of comorbidities, extra-intestinal manifestations, and the use of PPI were found to be associated with CDI.
authors.affiliation: Victor W. Fazio, MD Center for Inflammatory Bowel Disease, Digestive Disease Institute/A31, The Cleveland Clinic Foundation, 9500 Euclid Ave., Cleveland, OH 44195, USA. wangy3@ccf.org
authors.forename: Yinghong
authors.initials: Y
authors.lastname: Wang
authors.forename: Ashish
authors.initials: A
authors.lastname: Atreja
authors.forename: Xianrui
authors.initials: X
authors.lastname: Wu
authors.forename: Bret A
authors.initials: BA
authors.lastname: Lashner
authors.forename: Aaron
authors.initials: A
authors.lastname: Brzezinski
authors.forename: Bo
authors.initials: B
authors.lastname: Shen
mesh_terms: D000328:Adult; D016360:Clostridioides difficile; D004761:Enterocolitis, Pseudomembranous / Q000175:diagnosis / Q000382:microbiology*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D005260:Female; D006801:Humans; D043183:Irritable Bowel Syndrome / Q000382:microbiology*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016133:Polymerase Chain Reaction / Q000379:methods*; D012189:Retrospective Studies