Urolithiasis in adults with congenital megaureter.

The primary presentation of congenital megaureter in adults is rare. Development of urolithiasis may lead to this unusual underlying diagnosis. Urinary tract stones can form either within the dilated ureteral segment or in a part of the upper urinary tract proximal to the abnormal ureteral segment. We report two cases of nephrolithiasis that occurred in adults found to have segmental megaureter. The first case is that of a 58-year-old man who presented with left lower quadrant pain. Computed tomography scan revealed a 2-cm stone in the distal left ureter within an area of isolated segmental distal ureteral dilation. The second case is a 48-year-old man who developed recurrent renal urolithiasis associated with isolated distal megaureter.Although a rare condition in adults, congenital megaureter may present when kidney stones develop as a result of the ureteral abnormality. Typically, stones will develop within the dilated segment of ureter. Atypically, stones may develop away from the site of the underlying abnormality. Congenital megaureter is a diagnosis that urologists and radiologists need to consider in the setting of isolated distal ureteral dilation, as the diagnosis of adult megaureter may require more involved surgical measures to prevent recurrence of adverse symptoms.