Spontaneous nephro-duodenal fistula.

Nephroduodenal fistulas are an uncommon clinical entity characterized by upper abdominal pain and associated with pyelonephritis and renal calculus formation. Most of the recent cases reported are secondary to inflammatory changes in the kidney. Two cases are reported here, one of a nephroduodenal fistula and another of a combined nephroduodenal and nephrocolic fistulae. Carefully monitored X-ray studies determined in both cases the exact site and extent of the fistulae. The optimal treatment is nephrectomy.