title: Densities of rectal peptide YY and somatostatin cells as biomarkers for the diagnosis of irritable bowel syndrome.
abstract: Irritable bowel syndrome (IBS) is a common chronic disorder. IBS diagnosis is a diagnosis of exclusion since there are no blood tests, radiological or endoscopic examinations for this disorder. Although several attempts have been made to develop a symptoms-based diagnosis, such systems are not widely used in clinics. Several tests and examinations measuring pathological findings in IBS have been considered for the diagnosis of IBS, but none of them has proved useful as a biomarker. Abnormalities in the cell densities of rectal peptide YY (PYY) and somatostatin cells have been reported in IBS patients. The aim of the present study was to determine the utility of these abnormalities as biomarkers for the diagnosis of IBS. Patients with IBS established according to Rome III criteria (n = 101) were included in this study (71 females and 30 males with a mean age of 35 years; range 18-61 years), and 62 healthy subjects (38 females and 24 males with a mean age of 41 years; range 18-65 years) were recruited as controls. Both the patients and controls underwent colonoscopy during which rectal biopsy samples were taken. The tissue samples were immunostained for PYY and somatostatin, and the number of stained cells was quantified relative to both the area of epithelial cells and per microscopic field. The density of PYY cells was significantly lower in IBS patients than in the healthy controls (P < 0.0001); receiver operator characteristic (ROC) analysis revealed an area under the ROC curve (AUC) of 0.99. The somatostatin cell density in IBS patients was higher than in the controls (P < 0.0001); ROC analysis revealed an AUC of 0.86. The densities of the rectal PYY and somatostatin cells appear to be clinically effective biomarkers for IBS. Furthermore, measurement of these parameters is inexpensive, rapid and does not require considerable experience or sophisticated equipment.
authors.affiliation: Division of Gastroenterology, Department of Medicine, Stord Hospital, Stord, Norway; Division of Gastroenterology, Department of Clinical Medicine, University of Bergen, Bergen, Norway; National Centre for Functional Gastrointestinal Disorders, Department of Medicine, Haukeland University Hospital, Bergen, Norway. Electronic address: magdy.el-salhy@helse-fonna.no.
authors.forename: Magdy
authors.initials: M
authors.lastname: El-Salhy
authors.affiliation: Division of Gastroenterology, Department of Clinical Medicine, University of Bergen, Bergen, Norway; National Centre for Functional Gastrointestinal Disorders, Department of Medicine, Haukeland University Hospital, Bergen, Norway. Electronic address: jan.hatlebakk@helse-bergen.no.
authors.forename: Jan Gunnar
authors.initials: JG
authors.lastname: Hatlebakk
authors.affiliation: Division of Gastroenterology, Department of Clinical Medicine, University of Bergen, Bergen, Norway; National Centre for Functional Gastrointestinal Disorders, Department of Medicine, Haukeland University Hospital, Bergen, Norway. Electronic address: odd.helge.gilja@helse-bergen.no.
authors.forename: Odd Helge
authors.initials: OH
authors.lastname: Gilja
authors.affiliation: Division of Gastroenterology, Department of Clinical Medicine, University of Bergen, Bergen, Norway; National Centre for Functional Gastrointestinal Disorders, Department of Medicine, Haukeland University Hospital, Bergen, Norway. Electronic address: trygve.hausken@helse-bergen.no.
authors.forename: Trygve
authors.initials: T
authors.lastname: Hausken
mesh_terms: D000293:Adolescent; D000328:Adult; D015415:Biomarkers / Q000378:metabolism; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D043183:Irritable Bowel Syndrome / Q000175:diagnosis / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D019894:Peptide YY / Q000378:metabolism*; D012372:ROC Curve; D012007:Rectum / Q000378:metabolism* / Q000473:pathology; D013004:Somatostatin / Q000378:metabolism*; D055815:Young Adult
chemical_list: D015415:Biomarkers; D019894:Peptide YY; D013004:Somatostatin
keywords: Biomarkers; Diagnosis; Immunohistochemistry; Irritable bowel syndrome; PYY; Somatostatin