Point-of-Care Ultrasound Identifies Urinoma Complicating Simple Renal Colic: A Case Series and Literature Review.

BACKGROUND: Renal colic is a frequently encountered diagnosis among emergency department patients. Point-of-care (POC) ultrasound has taken on an increasingly important role in the diagnostic strategy of this disease, as it has been shown to be an effective modality for diagnosis and for guiding management. The primary pathology that the emergency physician will evaluate for in cases of suspected renal colic is hydronephrosis, which is a dilatation of the renal pelvis and calyces resulting from a distal obstruction such as a ureteral stone. However, other significant findings can be seen, one of which is the extravasation of urine around the kidney secondary to a forniceal, or calyceal, rupture. CASE SERIES: We present three cases of unanticipated perinephric fluid collections identified initially on POC ultrasound in cases of suspected simple renal colic. Concomitant hydronephrosis was also seen in each of these cases. Why Should an Emergency Physician Be Aware of This? While the utilization of POC ultrasound in cases of suspected renal colic increases, we should be prepared to encounter and identify perinephric fluid collections in our evaluations. Although the ideal management of these cases is not completely defined from the current literature, we benefit from knowing how to identify these on POC ultrasound, understanding the underlying pathophysiology, and appreciating the possibility of complications that may arise.