Lower Urinary Tract

Interstitial cystitis usually occurs in elderly women, who present with lower abdominal or perineal pain and urinary frequency. The lesion can involve anywhere in the bladder. Histologically, the lesion is a mucosal ulceration covered by fibrin and necrotic material. The underlying lamina propria and muscularis show edema, hemorrhage, granulation tissue, and a mononuclear cell infiltrate. Mast cells are frequently observed (Fig. 14.1).