[A case of spontaneous pyeloduodenal fistula].

A 71-year-old man was admitted for right loin pain and fever. DIP showed a non-visualizing right kidney. Retro- and antigrade pyelography demonstrated right hydronephrosis secondary to uretero-pelvic junction obstruction with leakage of the dye from the right kidney into the duodenum. Diagnosis of spontaneous pyeloduodenal fistula was confirmed at the operation. Right pyeloplasty was performed after closure of the duodenum. We believe that this is the 9th case reported in the Japanese literature.