Emphysematous pyelonephritis in a diabetic patient

Correspondence to Dr Thomas C Winter III; tom.winter@utah.edu Description A 49-year-old man with morbid obesity, hypertension and poorly controlled type 2 diabetes mellitus presented to the emergency department with ongoing shortness of breath, leukocytosis of 26 000/uL, lactate of 5.6 mmol/L and positive urinalysis. CT scan of the abdomen and pelvis without intravenous or oral contrast demonstrated gas replacing the majority of the left renal parenchyma, tracking inferiorly into the proximal left ureter (figure 1, white arrowhead), with two adjacent subcentimeter stones in the distal ureter (figure 2, white arrow). A radiologic classification system based on CT findings may help guide treatment.2 In this scheme, when there is viable renal parenchyma, first-line therapy consists of antibiotic therapy, fluid resuscitation, and glycaemic control, with percutaneous renal drainage, with or without ureteral stenting, usually performed as well.3 While favourable outcomes have been reported with non-invasive therapy alone,4 studies demonstrate significantly decreased mortality in patients treated with percutaneous drainage.5 In the setting of diffuse and severe infection, with findings of extensive parenchymal destruction on CT and/or absence of functional kidney demonstrated on nuclear medicine renography, or when there is a failure to respond to first-line treatment, nephrectomy may be indicated.1 3 6 Learning points Emphysematous pyelonephritis is a life-threatening infection seen in patients with diabetes and is caused by gas-forming organisms such as Escherichia coli and Klebsiella and Proteus species.