Retrocaval Ureter: An Uncommon Cause of Hydroureteronephrosis

Retrocaval ureter or circumcaval ureter is a rare developmental anomaly of inferior vena cava (IVC) where the ureter lies posterior to IVC, again to cross anteriorly below. Right ureter is most commonly though not exclusively involved. It is most commonly asymptomatic, but sometimes it may lead to stasis owing to obstruction of ureter which leads to hydronephrosis with proximal hydroureter. We present a case of retrocaval ureter in a young female patient presenting with recurrent right flank pain.