Proctitis is similar to proctosigmoiditis but is not necessarily associated with proximal extension of disease into the colon and usually does not evolve into ulcerative colitis. If proximal extension does occur, it usually does so within the first 2 years of initial diagnosis. Proctitis involves mucosal cell loss, acute inflammation of the lamina propria, eosinophilic crypt abscess, and endothelial edema of the arterioles. These may improve or progress with subsequent fibrosis of connective tissue and endarteritis of the arterioles, resulting in rectal tissue ischemia and leading to mucosal friability, bleeding, ulcers, strictures, and fistula formation.
Incidence is higher in Jewish persons.
The disease may run its natural course of exacerbations and remissions but is usually more prolonged and severe in patients with immunodeficiency disorders. Presentations may resemble dermatitis or decubitus ulcers in debilitated, bedridden patients. A secondary bacterial infection may be present. Radiation-induced proctitis Early symptoms include tenesmus and diarrhea that resolve shortly after the treatment period. C-reactive protein is elevated in patients with extensive pancolitis but is always normal in patients with distal disease only.