[Six cases of spontaneous peripelvic extravasation from the renal pelvis]

The diagnosis and management of 6 patients with spontaneous non-traumatic urinary extravasation are reported. It is important to distinguish extravasation of the fornical backflow type from that owing to frank rupture of the diseased renal pelvis. In Japan, 26 cases of spontaneous peripelvic extravasation and 29 cases of spontaneous pelvic rupture have been reported. Most of them were caused by calculous ureteral obstruction. Many of the cases of spontaneous peripelvic extravasation could be managed conservatively, and many of the cases of spontaneous pelvic rupture often required surgical treatment due to the patient's clinical condition, the persistence of obstruction or extravasation, or the presence of complication of extravasation such as urinoma or abscess. All of our 6 cases were managed conservatively and had no complications.