A. Almahameed 1 , S. Baghdasarian 2 , S. Frost 2 ; 1 Cleveland Clinic Foundation, Shaker Heights, OH; 2 The Cleveland Clinic Foundation, Cleveland, OH LEARNING OBJECTIVES: 1) Recognize the potential for severe complications in diabetic patients with urinary tract infection. 2) Diagnose renal emphysema. 3) Recognize that prompt medical and surgical treatment is essential to decrease the high rate of mortality associated with emphysematous pyelonephritis and pyelitis. CASE INFORMATION: A 48 yo black woman with multiple sclerosis and diabetes mellitus presented with abdominal pain, fever, and dysuria 3 days after starting ciprofloxacin for presumed urinary tract infection (UTI) . Physical exam demonstrated T=39C, HR=130, BP=150/80, and tenderness in the left lower quadrant without peritoneal signs. Laboratory investigation revealed WBC=9.91, Cr=1.2, and BUN=25. Urinalysis showed trace leukocyte esterase, WBC=6-10, 2+ blood, and RBC=0-3. Ampicillin and gentamicin were administered. CT scan of the abdomen was obtained demonstrating slight enlargement of the left kidney with stranding of the perinephric fat, and a dilated left renal pelvis and proximal ureter containing pockets of gas. Hydronephrosis, pyelonephritis, and emphysematous pyelitis were diagnosed and the patient promptly underwent intraoperative cystoscopy to evaluate for ureteral obstruction. Debris occluding the left ureter was visualized and a ureteral stent was deployed. Urine and blood cultures revealed Proteus Mirabilis and Aerococcus Urinae. The patient improved quickly and was discharged on the fourth day of hospitalization to complete antibiotic treatment with Augmentin. DISCUSSION: UTI is a significant problem in diabetic patients, and complications such as pyelonephritis, renal or perirenal abscess, focal or multifocal bacterial nephritis, xanthogranulomatous pyelonephritis, and renal papillary necrosis can occur. Emphysematous pyelonephritis (air in the renal parenchyma), and emphysematous pyelitis (air in the collecting system) are complications that occur more frequently in diabetic than in non-diabetic patients. Early diagnosis of emphysematous complications is crucial due to the high rate of mortality in patients whose diagnosis is delayed. Radiographic confirmation is essential (preferably by abdominal CT scan) as the history, physical exam and laboratory findings are rarely diagnostic. Emphysematous pyelonephritis responds poorly to antibiotics alone, with mortality rates as high as 80%. Surgical intervention is virtually mandatory, with nephrectomy lowering mortality to 20% or less. Emphysematous pyelitis is less critical, with an overall mortality of 20%. It is often associated with urinary tract obstruction, and responds well to intravenous antibiotics and obstruction relief.