[A Case of Emphysematous Pyelonephritis after Starting Treatment for Acute Pyelonephritis].

A 68-year-old man sought evaluation at our emergency department in the early morning of day X with a feverfor3 days. The physical examination revealed pain in the left back, and an abdominal computed tomography (CT) showed a high density of fatty tissue around the left kidney. With a diagnosis of left acute bacterial pyelonephritis, he was hospitalized, antibacterial drug treatment was started, and he was transferred to our department on the same day. He had uncontrolled type 2 diabetes mellitus and had been treated with multiple drugs at another hospital. A decrease in blood pressure and respiratory failure was observed at night, and when contrast CT was performed the next morning, emphysema was observed in the parenchyma of the left kidney. The patient was diagnosed with class 2 left emphysematous pyelonephritis according to the classification of Huang et al. Double J stenting in the left ureter and conservative treatment were performed. Antibiotic treatment was continued and CT-guided percutaneous catheter drainage was performed on day 11. His general condition improved and he was discharged on day 32.