This is a diabetic female with history of E. coli pyelonephritis, completing intravenous antibiotics 2 weeks prior to this CT. She presented with flank pain and low-grade fever.

CT demonstrates several areas of cortical hypoattenuation consistent with bilateral pyelonephritis, with coalescing subcapsular and parenchymal fluid collections of the left kidney, consistent with abscesses. The lack of well-defined thick, enhancing wall typical of renal abscesses may be due to the recent treatment with antibiotics, suggesting an evolving (either developing or subacute/resolving) component. The patient was managed conservatively with continued antibiotics and did not go undergo a drainage procedure.