Megacalycosis: report of two cases.

Congenital megacalycosis is a rare renal disorder consisting of caliceal dilatation without evidence of renal pelvic or ureteral obstruction. Since its first description in 1963, only a few cases have been reported. The defect is mostly unilateral, shows male predominance and does not disrupt the renal functions. We report on two male patients with bilateral megacalycosis and different clinical presentations. The first case was diagnosed in adolescence during examination for a urinary tract infection and was followed-up uneventfully for nearly ten years. The second case was found to have megacalycosis during the assessment of antenatal hydronephrosis. We aimed to emphasize the importance of considering megacalycosis in the differential diagnosis of both antenatal hydronephrosis and other causes of caliceal dilatation to prevent unnecessary diagnostic and therapeutic interventions.