Spontaneous peripelvic extravasation of urine.

Spontaneous peripelvic extravasation of urine is relatively uncommon. We experienced 11 cases of spontaneous peripelvic extravasation. Urinary obstruction was caused by calculi in 9 cases, invasion by sigmoid carcinoma in 1 case and ureteral tumour (transitional cell carcinoma) in 1. Six patients presented with signs of peritonitis and 4 out of 9 with calculus did not develop microhaematuria. It is important to differentiate peripelvic extravasation from other acute abdominal conditions. We must pay special attention to patients with signs of peritonitis and normal urinalysis.