Transcaval ureter: a rare embryological anomaly causing obstructive uropathy

Abstract

SUMMARYA 21-year-old woman presented with a longstanding history of episodic right flank pain related to fluid consumption and recurrent urinary tract infections. On examination, there was right costovertebral angle tenderness. Renal tract ultrasound demonstrated hydronephrosis and CT urography confirmed transcaval ureter. The patient's clinical presentation was likely due to obstruction associated with the right ureter passing through the opening created by the duplicated segment of the inferior vena cava. While asymptomatic transcaval ureter can be managed conservatively, severe symptoms or complications of ureteric obstruction may require surgical treatment. In this case, treatment comprised a laparoscopic ureteroureterostomy with an end-to-end anastomosis between the proximal and distal sections of the right ureter. The patient's postoperative recovery was uneventful and she reported resolution of the flank pain during the one year of follow-up. BACKGROUND

Computed tomographic appearance of transcaval ureter in two dogs and three cats: A novel CVC congenital malformation

“…In accordance with the human literature, all dogs and cats included in this study reported a right-sided distribution of the transcaval ureter ( 8 – 11 ). Only patient number 3 had limited clinical signs related to the urinary system, consistent with hematuria which is also reported in human medicine ( 8 , 9 ). All the patients included in this case series displayed normal kidney values.…”

“…For example, in cases of ureteral ectopia, the normal renal function is possibly related to the congenital origin of the anomaly and the adaptive process of the urinary tract during the development (26). Patient number 2 had intermittent vomiting despite absent gastrointestinal changes on CT. Flank pain might be considered in the differentials as a possible reason for the clinical signs, triggered by colic irradiation due to ureteral stretch, as reported in humans (9). However, a significant limitation regarding this hypothesis is that no additional procedures, such as gastrointestinal endoscopy and biopsy, were performed to further investigate the cause of vomiting.…”

“…In human medicine, surgical management involves resection of the ureter and an ureteroureteric anastomosis anterior to the IVC ( 9 ). To the best of our knowledge, there is no surgical procedure described in veterinary medicine for the treatment of a transcaval ureter since this congenital malformation has never been described and its clinical impact is still uncertain.…”

“…Contrastenhanced multidetector computed tomography (MDCT) for detecting and characterizing CVC anomaly is recommended due to the excellent visualization of the CVC and its relationship with the ureters (5). Transcaval ureter is a rare embryological abnormality of the inferior vena cava (IVC) rarely described in human medicine, in which a segmental duplication of this vessel creates a venous ring that encircles the right ureter (8)(9)(10)(11). There are few reports on transcaval ureter in human medicine, and different theories about its embryological development were formulated (2,(8)(9)(10)(11).…”

“…Transcaval ureter is a rare embryological abnormality of the inferior vena cava (IVC) rarely described in human medicine, in which a segmental duplication of this vessel creates a venous ring that encircles the right ureter (8)(9)(10)(11). There are few reports on transcaval ureter in human medicine, and different theories about its embryological development were formulated (2,(8)(9)(10)(11). According to the supracardinal model, transcaval ureter arises when the right posterior cardinal and right supracardinal veins fail to regress in post-renal segment, resulting in a partial duplication of IVC that creates a venous ring through which the right ureter extends.…”