Evaluation of the inflammatory infiltrate in pouchitis with 111In-labeled granulocytes

Abstract

Background: The aim of this study was to elucidate the inflammatory infiltrate in pouchitis and define the changes following metronidazole therapy.

Methods: Twenty-seven patients underwent functional grading, sigmoidoscopic and histological scoring, 111In-labeled granulocyte scanning, and 4-day fecal collections for 111In-labeled granulocyte excretion. Six of the patients with pouchitis underwent repeat studies after 1-month treatment with metronidazole, 400 mg three times daily.

Results: The grade of macroscopic inflammation in the pouch mucosa (sigmoidoscopic score) correlated well with the acute histological score (P < 0.0001), chronic histological score (P < 0.001), 4-hour 111In scan (P < 0.001), 24-hour 111In scan (P < 0.001), and with 4-day fecal 111In excretion (P < 0.001). After metronidazole therapy there was decreased inflammatory grade sigmoidoscopically and histologically on the 4- and 24-hour scans and decreased 4-day fecal 111In granulocyte excretion.

Conclusions: This study confirms that the inflammatory infiltrate in pouchitis is acute or chronic, is characterized by neutrophils, is usually localized to pouch mucosa, and is always decreased after metronidazole therapy.