title: Elevated fecal levels of eosinophil granule proteins predict collagenous colitis in patients referred to colonoscopy due to chronic non-bloody diarrhea.
abstract: OBJECTIVE
  Colonoscopy with biopsy sampling is often performed to detect collagenous colitis (CC) and lymphocytic colitis (LC) in patients with chronic non-bloody diarrhea. However, the diagnostic yield is low and incurs high costs. Fecal calprotectin (FC) and myeloperoxidase (MPO) indicate intestinal inflammation in ulcerative colitis (UC) and Crohn's disease (CD). In CC, elevated fecal levels of eosinophil protein X (EPX) and eosinophil cationic protein (ECP) have been reported. We aimed to evaluate if F-EPX, F-ECP, FC, and F-MPO could predict the diagnostic outcome in patients with chronic non-bloody diarrhea referred to colonoscopy. We also evaluated serum (S) EPX and ECP in this regard.
  
  
  METHODS
  Of 67 included patients, 63 (94%) underwent colonoscopy with biopsy sampling. Fecal EPX, F-ECP, FC, F-MPO, S-EPX, and S-ECP were analyzed.
  
  
  RESULTS
  Diagnostic outcome: normal: n = 46 (73%), CC: n = 9 (14%), LC: n = 4 (6%), UC: n = 2 (3%), CD: n = 2 (3%). Higher levels of F-EPX and F-ECP were found in CC compared to a normal diagnostic outcome (p = 0.01). No change was noted in any of the fecal markers in LC. When all of the fecal markers were normal the probability of a normal diagnostic outcome was 92%. We found no differences in S-EPX and S-ECP between the groups.
  
  
  CONCLUSIONS
  Elevated F-EPX and F-ECP could predict CC. None of the fecal markers predicted LC. Serum-EPX and S-ECP are not useful for the diagnosis of CC, LC, UC, or CD. With normal levels in all of the analyzed fecal markers, there is a low probability of a pathologic diagnostic outcome.
authors: a Department of Medical Sciences, Gastroenterology Research Group , Uppsala University , Uppsala , Sweden ;
authors: Michael
authors: M
authors: Wagner
authors: b Department of Clinical Sciences, Department of Gastroenterology and Nutrition , Skåne University Hospital, Lund University , Malmö , Sweden ;
authors: Klas
authors: K
authors: Sjöberg
authors: c Department of Medicine , Ystad Hospital , Ystad , Sweden ;
authors: Lina
authors: L
authors: Vigren
authors: d Department of Pathology , University and Regional Laboratories Region Skåne, Skåne University Hospital , Malmö , Sweden ;
authors: Martin
authors: M
authors: Olesen
authors: e Department of Clinical Sciences, Department of Medicine , Skåne University Hospital, Lund University , Malmö , Sweden.
authors: Cecilia
authors: C
authors: Benoni
authors: b Department of Clinical Sciences, Department of Gastroenterology and Nutrition , Skåne University Hospital, Lund University , Malmö , Sweden ;
authors: Ervin
authors: E
authors: Toth
authors: a Department of Medical Sciences, Gastroenterology Research Group , Uppsala University , Uppsala , Sweden ;
authors: Marie
authors: M
authors: Carlson
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000032:analysis; D001706:Biopsy; D002908:Chronic Disease; D046729:Colitis, Collagenous / Q000175:diagnosis*; D003113:Colonoscopy; D003967:Diarrhea / Q000175:diagnosis*; D047150:Eosinophil Cationic Protein / Q000032:analysis / Q000097:blood; D047091:Eosinophil Granule Proteins / Q000032:analysis*; D047208:Eosinophil-Derived Neurotoxin / Q000032:analysis / Q000097:blood; D005243:Feces / Q000737:chemistry*; D005260:Female; D006471:Gastrointestinal Hemorrhage / Q000175:diagnosis*; D006801:Humans; D039841:Leukocyte L1 Antigen Complex / Q000032:analysis; D008297:Male; D008875:Middle Aged; D055815:Young Adult
chemical_list: D015415:Biomarkers; D047091:Eosinophil Granule Proteins; D039841:Leukocyte L1 Antigen Complex; D047208:Eosinophil-Derived Neurotoxin; D047150:Eosinophil Cationic Protein
keywords: Collagenous colitis; eosinophil; eosinophil cationic protein; eosinophil protein X; fecal markers