Fetal Urinoma Due to Circulatory Disorders in an Umbilical Artery: Case Report.

Fetal urinoma is defined as an encapsulated accumulation of extravasated urine within the perirenal space or retroperitoneum. It is an uncommon finding in prenatal practice, and the vast majority of known cases are strongly associated with the existence of a urinary obstruction, such as posterior urethral valves, ureteropelvic junction obstruction, or ureterocele. We report a unique case of prenatally detected fetal bladder urinoma that occurred in the absence of an apparent obstructive uropathy, but was associated with extensive ischemic necrosis and calcifications of adjacent bladder wall, coexistent with signs of vascular supply decompensation.

Imaging and differential diagnosis of suprarenal masses in the fetus.

Prenatal sonography and magnetic resonance imaging of suprarenal fetal masses is presented, along with clinical information and follow-up. Imaging pearls and differential considerations for each diagnosis will be discussed. Fetal suprarenal mass diagnoses include neuroblastoma, extralobar pulmonary sequestration, congenital adrenal hyperplasia, partial multicystic dysplastic kidney, renal duplication, urinoma, gastric duplication cyst, and splenic cyst. Recognizing the range of malignant and benign suprarenal fetal masses that can present on prenatal imaging can help guide patient counseling and management.

The fetal urinoma revisited.

The fetal urinoma is a rare but important diagnosis, as it indicates substantial underlying obstruction with implications for the functionality of the affected kidney. This case series describes a single center's experience with the diagnosis and management of fetal urinomas. All 25 cases were diagnosed or referred to our medical center over an 11-year period. Most cases were secondary to either posterior urethral valves or ureteropelvic junction obstruction. Fetal interventions, including percutaneous drainage of the urinoma and cystoscopic alleviation of bladder outlet obstruction, were performed in 4 cases.

Fetal urinoma in females without obstructive uropathy.

OBJECTIVE: Prenatal diagnosis of urinomas has long been established with underlying obstructive uropathy generally responsible for urinary extravasation. Because urinoma formation represents a pop-off mechanism in cases of posterior urethral valves, the number of affected males greatly exceeds the number of females. Fetal urinoma has rarely been reported without obstruction and in females it has only been described as a consequence of a complicated amniocentesis. METHODS: Three cases of fetal urinoma in female fetuses without any dilatation of the urinary tract are described. Since the fetus remained healthy, they were all conservatively managed. RESULTS: Two urinomas resolved after birth and 1 exhibited significant regression. In the second case, a compressed kidney was visualized with fetal MRI. Renal function was impaired in cases 1 and 3 and absent in case 2 (the kidney was no longer visualized). CONCLUSIONS: Fetal urinomas can occur even in the absence of urinary tract obstruction and in a low-pressure system as is found in female fetuses. Fetal MRI may help both visualize the ipsilateral kidney and differentiate the mass from other conditions. In a healthy fetus, fetal urinomas can be conservatively managed, but renal function after birth is often absent or impaired. Whether or not in utero aspiration may be beneficial for the preservation of renal function remains unclear.