This document discusses various congenital kidney and ureter abnormalities including renal agenesis, horseshoe kidneys, congenital cysts, megaureter, ectopic ureter, and ureterocele. It provides details on the presentation, diagnosis and management of each condition. Bilateral renal agenesis is usually fatal in newborns due to pulmonary issues. Unilateral renal agenesis often has no symptoms but can be associated with other anomalies. Horseshoe kidneys occur when the lower poles fuse and predispose to obstruction. Congenital cysts are common kidney lesions that arise from nephrons. Ectopic kidneys are not in the normal position and predispose to obstruction. Me