후복막 낭종으로 오인된 일측성 거대수뇨관

Unilateral Marked Hydroureter Misdiagnosed as a Retroperitoneal Cyst

Hydroureter could occur in a state where the whole ureter was remarkably expanded. The causes of occurrence are anatomical urinary tract obstruction or vesicoureteral reflux, and it could occur unilaterally or bilaterally according to its reason. A 38-year-old man presented with left flank pain. Abdominal CT showed a severely atrophied left kidney and a large retroperitoneal cyst near the left kidney. The pathologic finding showed that the cyst wall is composed of transitional epithelium, lamina propria, muscle, and adventitia, and final diagnosis was hydroureter. The unilateral marked hydroureter misdiagnosed as a retroperitoneal cyst was quite rare. We report on this rare case with literature.