Abstract: | A case of giant hydronephrosis due to ureteropelvic junction obstruction in an 18-year-old boy is reported. The patient had been told to undergo an operation for the left hydronephrosis at 2 years of age. However, he stayed away from hospital until he presented at our clinic with nausea caused by a large abdominal mass. Radiological evaluation revealed a left giant hydronephrosis with no function and slight compensatory hypertrophy in the right kidney. Left nephrectomy was performed and the pelvic capacity was approximately 7,700 ml. Histopathological examination showed muscular hyperplasia at the ureteropelvic junction. The term giant hydronephrosis may be defined as a hydronephrosis the contents of which are greater than 1,000 ml. Three hundred twenty four cases of giant hydronephrosis in the literature are reviewed and the age, sex, side involved, pelvic capacity, etiology, and relation to hypertension are discussed. |