Emphysematous cyst infection in autosomal dominant polycystic kidney disease

Abstract

A 51-year-old man was admitted to our hospital with flank pain and fever. Peritoneal dialysis had been started for endstage renal failure secondary to autosomal dominant polycystic kidney disease (ADPKD) at the age of 45 years, and he was switched to hemodialysis because of ultrafiltration failure after 4 years. Two years later, he suffered from right flank pain and fever (38.5 C). Magnetic resonance imaging revealed marked enlargement of both kidneys with multilocular complicated cysts bilaterally (Fig. 1). Although blood culture did not identify a pathogenic organism, his fever subsided after 3 months of antibiotic therapy. Transcatheter arterial embolisation (TAE) was performed to reduce kidney volume bilaterally according to the previously reported method [1]. Severe bilateral flank pain and fever occurred from 12 h after TAE, but subsided by the fourth day. At 7 days after TAE, right flank pain and high fever recurred. Computed tomography disclosed multiple lesions (arrows) with airfluid levels throughout the right kidney (Fig. 2). Fluid aspirated from these cysts grew Escherichia coli that was resistant to multiple antibiotics except meropenem. However, his fever persisted despite treatment with meropenem. The white blood cell (WBC) count rose to 29,900/lL and C-reactive protein was 24.8 mg/dL. His albumin was 1.4 mg/dL, total cholesterol was 96 mg/dL, and he was not diabetic. Finally, right nephrectomy was performed. After surgery, his fever subsided, WBC declined to 6,700/lL, and CRP decreased to 1.1 mg/dL. Emphysematous infection of renal cysts in ADPKD is a potentially lethal condition that requires nephrectomy, like emphysematous pyelonephritis. This was the first case among a total of 812 patients receiving renal TAE from 1996. When gas-forming infection occurs in the collecting system as well as the renal parenchyma, emphysematous pyelonephritis is diagnosed, which is a life-threatening disorder. Sooraj et al. used the term emphysematous polycystic renal infection (EPRI) for emphysematous infection in ADPKD patients. It is also common in diabetics and post-transplant patients [2]. Escherichia coli and Clostridium perfringens have been reported to be the causative organisms. Hyperglycemia or an impaired host response to sepsis are considered to result in EPRI [2, 3]. The present patient was not diabetic, but had malnutrition with hypoalbuminemia and hypocholesteremia. His immunocompromized status due to malnutrition may have contributed to the occurrence of this condition. M. Yamanouchi (&) Y. Ubara K. Takaichi Nephrology Center, Toranomon Hospital, 2-2-2 Toranomon, Minato-ku, Tokyo 105-8470, Japan e-mail: masayuki.y@coast.ocn.ne.jp