title: Antibodies to Escherichia coli outer membrane porin C in the absence of anti-Saccharomyces cerevisiae antibodies and anti-neutrophil cytoplasmic antibodies are an unreliable marker of Crohn disease and ulcerative colitis.
abstract: OBJECTIVE
  Antibodies to Escherichia coli outer membrane porin C (anti-OmpC), Saccharomyces cerevisiae, and neutrophil-specific nuclear antigens are associated with inflammatory bowel disease (IBD) in children and young adults. We hypothesized that anti-OmpC, in the absence of anti-S cerevisiae antibodies (ASCA) and antineutrophil cytoplasmic antibodies (ANCA), is an assay that overestimates the presence of Crohn disease (CD) and ulcerative colitis (UC).
  
  
  METHODS
  A retrospective review of patients evaluated at our institution between January 2002 and June 2006 revealed that 170 had serodiagnostic immunological assays performed as part of an evaluation for possible IBD. The assays were screened for a pattern in which anti-OmpC was present in the absence of ASCA and ANCA.
  
  
  RESULTS
  Seven patients between 3 and 20 years of age were discovered to be positive for anti-OmpC but negative for ASCA and ANCA. These patients were determined to have significant medical conditions without combined radiographic, endoscopic, or histological evidence of IBD. Despite the reported 85% positive predictive value of anti-OmpC for IBD, none of the 7 patients with isolated anti-OmpC had a diagnosis of CD or UC.
  
  
  CONCLUSIONS
  Anti-OmpC, in the absence of ASCA and ANCA, is a serological pattern noted in a subset of medically complex cases in children and young adults without CD or UC.
authors.affiliation: Division of Gastroenterology, Department of Pediatrics, University of Florida College of Medicine, Gainesville, USA.
authors.forename: Michael K
authors.initials: MK
authors.lastname: Davis
authors.forename: Joel M
authors.initials: JM
authors.lastname: Andres
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Jolley
authors.forename: Donald A
authors.initials: DA
authors.lastname: Novak
authors.forename: Allah B
authors.initials: AB
authors.lastname: Haafiz
authors.forename: Regino P
authors.initials: RP
authors.lastname: González-Peralta
mesh_terms: D015746:Abdominal Pain; D000293:Adolescent; D000328:Adult; D019268:Antibodies, Antineutrophil Cytoplasmic / Q000097:blood*; D000907:Antibodies, Bacterial / Q000097:blood*; D001466:Barium Sulfate; D015415:Biomarkers / Q000097:blood; D002648:Child; D002675:Child, Preschool; D003093:Colitis, Ulcerative / Q000097:blood / Q000175:diagnosis* / Q000276:immunology; D003424:Crohn Disease / Q000097:blood / Q000175:diagnosis* / Q000276:immunology; D003937:Diagnosis, Differential; D003967:Diarrhea; D004797:Enzyme-Linked Immunosorbent Assay; D004926:Escherichia coli / Q000276:immunology; D005260:Female; D006801:Humans; D008297:Male; D018272:Porins / Q000276:immunology*; D011237:Predictive Value of Tests; D011860:Radiography, Abdominal; D012189:Retrospective Studies; D012441:Saccharomyces cerevisiae / Q000276:immunology*; D014057:Tomography, X-Ray Computed
chemical_list: D019268:Antibodies, Antineutrophil Cytoplasmic; D000907:Antibodies, Bacterial; D015415:Biomarkers; C113724:OmpC protein; D018272:Porins; D001466:Barium Sulfate