Horseshoe kidney with complete unilateral duplication of ureter and pelvicalyceal system--a case report.

INTRODUCTION Horseshoe kidney is the most common fusion abnormality in the kidney and occurs in 1 per 400 people with the male female ratio of 2:1.(1) Duplication of renal collecting system is the most common upper tract anomaly with an incidence of 0.5-0.8%.(2) Unilateral duplication is six times more frequent than bilateral duplication, with equal incidence on right and left sides.(3) However duplicated system in a horseshoe kidney is very rare. Most patients with horseshoe kidney are asymptomatic, up to 80% have hydronephrosis, about 20% develop renal calculi and 1/3-1/2 of cases have another associated anomaly.(2) The aim of this report is to highlight its rarity and technical difficulties in its management.