A case report of a young patient (born in 1980) with a 2-year history of chronic ulcerative proctocolitis was described. Checking colonoscopy 6 months from the beginning of disease showed multiple and even confluent polypoid lesions in transverse gut starting from hepatic flexure in addition to diffuse inflammatory rectosigmoideal changes.
Biopsy found only colic mucosa without any tumorous structures. Five months later the patient's state got worse accompanied instantly by vomiting, weight loss and malabsorption symptoms.
A duodenocolic fistula was supposed according to gastroduodenoscopy and biopsy. Because of progressive suffering of the patient colectomy with ileoduodenoanastomosis and ileosigmoidoanastomosis was performed.
Polypous lesions were observed from the blind gut up to descendent colon and a transversoduodenal fistula was proved. The removed part of gut was completely changed into a dense network of elongated polypous lesions.
In microscopy, bigger polyps showed an inner stromal part often with bands of smooth muscle cells covered by nearly normal gut mucosa. Smaller polyps were formed by hypertrophic gut mucosa only.
At the base of polyps, a stagnation of gut contents was found as well as ulcerous defects of various depth. Macroscopy and microscopy of polypoid lesions formed by non-neoplastic gut mucosa were those of so called bizzare ("giant") inflammatory polyposis of the gut.
Up to now the patient's clinical picture and local finding in the stump of resected gut have been typical for chronic ulcerous colitis and polypous lesions were not revealed by checking investigations.