Cutaneous fistulas of the lumbar area are rarely diagnosed. The presented case concerned a 46-year old female patient who underwent surgical treatment in 2008, at the Department of General and Bariatric Surgery, and Emergency Medicine. After twelve months of ineffective conservative therapy of a purulent cutaneous fistula the patient was directed to the Department of Surgery for radical excision of the lesion. After performing additional diagnostic examinations the patient underwent planned surgery, including the complete excision of the fistula canal, which had no contact with the peritoneal cavity. Numerous deposits were observed in the lumen of the fistula. Chemical analysis of the abovementioned demonstrated a 100% content of calcium oxalate, characteristic of urolithiasis. The patient was discharged from the hospital on the eighth day after the operation in good general condition, and with a properly healing wound. Both patient history and examination were unable to definitely determine the cause of the fistula.