Spontaneous extravasation of urine during emergency intravenous pyelography

Abstract

Abstract During intravenous pyelography, spontaneous extravasation of contrast from the pelvicaliceal system into the renal sinus and beyond is rarely seen. The diagnosis in 4 patients with ureteric colic was confirmed by emergency pyelograms, and in each case extravasation of contrast was noted. The most likely explanation of spontaneous ‘pyelosinus back-flow’ is that the sudden increased intrapelvic pressure which occurs during ureteric colic results in minute tears of the caliceal fornix. Spontaneous extravasation of urine could explain the severe loin pain and pyrexia associated with ureteric colic. Complications are rare provided the calculus is passed and no treatment is required. The condition must be clearly distinguished from true rupture of the renal pelvis and ureter which may present as an acute abdomen, requiring urgent exploration and drainage.