Successful conservative treatment of bilateral emphysematous pyelonephritis in autosomal dominant polycystic kidney disease
A 57-year-old man with diabetes mellitus, systemic hypertension, and polycystic kidney disease presented with fever and left loin pain for 1 week. His medications included two oral anti-diabetic drugs (metformin and glimepiride) and two anti-hypertensive drugs. There was no history of dysuria or hematuria. Physical examination revealed pallor, bilateral pedal edema, pulse rate of 102/min, blood pressure of 160/100 mmHg, temperature of 39°C, and respiratory rate of 19/min. Abdomen examination revealed bilateral nodular enlarged kidneys with tenderness in the left renal angle. Respiratory system and cardiovascular system examinations were unremarkable. His hemoglobin (10.3 g/dL) was decreased and white blood cell count was increased to 13.8 × 109/L with neutrophils 84%, lymphocytes 12%, eosinophils 2%, and monocytes 2%. Platelet count was 364 × 109/L and 1.2% of reticulocyte count was normal. Blood sugar was 390 mg/dl, serum creatinine was 1.39 mg/dL, and the estimated four-variable MDRD GFR was 55 mL/min/1.73 m2. Blood gas analysis revealed high anion gap metabolic acidosis (pH, 7.26; pCO2, 25 mm Hg; HCO3, 19 meq/L; pO2, 128 mmHg; anion gap 16 meq/L; lactate, 1.5 meq/L; Na, 136 meq/L; K, 3.8 meq/L; and Cl 101 meq/L). Liver function tests, uric acid, calcium, inorganic phosphorus, and lipid profile were within normal limits. HBsAg, HIV, and anti-HCV antibody enzyme-linked immunosorbent assay were negative. Urine analysis showed 2+ ketone, 4+ glucose, and hematuria with 1+ proteinuria. Urine nitrite test was positive. There were 8–10 white blood cells per high-power field (hpf), 8–10 red blood cells per hpf, 12–15 pus cells per hpf, and no evidence of casts on microscopic examination of the urine sediment. Ultrasound revealed bilateral polycystic kidneys with features of thick wall and intracystic debris in one upper pole cyst of right kidney. Emergency non-contrast computerized tomogram of abdomen revealed features of bilateral emphysematous cyst infection [] with features of pyelonephritis. A provisional diagnosis of EPN with diabetic ketoacidosis was made. His initial management included intravenous antibiotics (piperacillin + tazobactum 4.5 gm q8h and levofloxacin 500 mg q24h), IV fluids, insulin infusion (regular insulin titrated to maintain capillary blood glucose range of 100–150 mg/dl), and supportive measures. Percutaneous aspiration of both the cysts was done under real-time ultrasound guidance on day 2. About 250 ml of purulent fluid was aspirated. Gram stain revealed multiple gram-negative bacilli. Urine and blood cultures showed no growth. Chest X-ray did not reveal any abnormality. Culture of pus revealed Escherichia coli (non-ESBL) sensitive to meropenem and pazufloxacin. Antibiotics were changed to meropenem, pazufloxacin from day 4. Patient became afebrile on day 6. Antibiotics were continued for a period of 3 weeks. Repeat ultrasound done after 3 weeks showed significant resolution of cyst collection on both sides. Patient was discharged on day 22 with oral antibiotics (faropenem and levofloxacin). Twelve weeks after discharge, patient is asymptomatic, with a serum creatinine of 1.04 mg/dL. He is presently on levofloxacin prophylaxis.