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

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

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.

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.

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.