[Spontaneous rupture of the urinary bladder].

A case of non-traumatic rupture of the urinary bladder is reported. The patient, a 52-year-old woman, was admitted to our clinic with the chief complaints of dysuria and gross hematuria after hemorrhoidectomy. Ultrasonography and CT scan showed a huge mass in Retzius' cavity. Then, rupture of the bladder was diagnosed through subsequent cystoscopy and cystography. During surgery, we recognized a large defect in the anterior wall of the urinary bladder associated with reddish-yellow fluid in the pelvic cavity. Histological findings showed no malignant change in the bladder. Various factors were suspected to be related to this spontaneous rupture of the urinary bladder.