Three patients with renocolic fistulas are presented. Antegrade or ret
rograde pyelography showed the fistula in one patient but was unsucces
sful in two others. CT demonstrated perinephric inflammation extending
to the colon, complex air-fluid collections within the kidney, or ext
ension of renal contrast into the colon. CT and direct pyelography com
plement each other for the diagnosis of renocolic fistulas.