The etiology and clinical characteristics of acute lower gastrointestinal bleeding in patients hospitalized for comorbid illnesses.

Abstract

Patients with acute lower gastrointestinal bleeding that starts after hospitalization for other comorbid illnesses have distinctive etiologies and clinical characteristics compared with ordinary patients admitted to the hospital with only bleeding. Rectal ulcer is an important but obscure cause of acute lower gastrointestinal bleeding in elderly patients with significant comorbid diseases.