Colonic endocrine cells in inflammatory bowel disease

Objectives. To study colonic endocrine cell types in patients with ulcerative colitis (UC) and Crohn's disease (CD). Setting. Departments of Medicine and Pathology, University Hospitals, Umea and Uppsala, Sweden. Subjects. Seventeen patients with UC (seven females and 10 males) and 11 patients with CD (five females and six males). Twenty-two patients (eight females and 14 males) operated on for colon carcinoma and without signs of inflammatory bowel disease were used as controls. Measurements. The colonic endocrine cell types were identified by immunohistochemical methods and quantified by computed image analysis. Results. The areas of the argyrophil cells as well as these immunoreactive to chromogranin A and serotonin were significantly increased in patients with both UC and CD, compared with those in the controls. In patients with CD, the areas of polypeptide YY(PYY)- and pancreatic polypeptide (PP)-immunoreactive cells were significantly reduced, whilst the area of enteroglucagon-immunoreactive cells was increased. There was no statistical difference in endocrine cell area between specimens with slight versus severe inflammation, except for PYY and enteroglucagon cell areas in patients with CD. Whilst the former cell area decreased, the latter increased in specimens with severe inflammation. The mean cellular area for each endocrine cell type did not differ between the controls and patients with UC or CD. Conclusions. The increase in the serotonin-immunoreactive cell area in patients with both UC and CD might be one of the factors causing reduced colonic contraction and increased intraluminal pressure observed in patients with inflammatory bowel disease. Furthermore, in patients with CD, the decreased PYY-immunoreactive cell area may explain the decreased absorption and increased secretion found in these patients.