Background: Chitosan derivatives have coagulant and tissue repairing activity. Objective: To test the activity of a polyglucosamine ( PG) together with a Standard Management protocol (SM) on the occult and obscure bleeding (OGIB) and clinical symptoms in patients suffering from colonic diverticulitis (COD).

Methods: Registry study comparing the combination SM and PG (1000 mg x3) Vs the SM only. Sixty patients divided into two group of 30 cases. At baseline, after 1 and 3 months of treatment the following variables were measured: OGIB, Hb, red cells count (RC), body weight (BW), abdominal circumference (AC), body mass index (BMI), hs-CRP, and daily gastrointestinal discomfort (DGID).

Results: The combination SM+PG was more active (p < 0.01) than SM in reducing OGIB (respectively -79 % Vs 65 %, the AC (-4.0 Vs 1.7 cm), the DGID (-91 % Vs -73 %) and hs-CRP (- 63% Vs -37 %. The Hb and RC increased more with SM+PG than with SM (t test p< 0.05). SM+PG showed to reduce of 77% the DGID just after a week of treatment.

Conclusion: SM+PG was found more effective than SM in reducing OGIB and all the sign and symptoms of COD.