Presentation
Flank pain, fever.
Patient Data
Striated right nephrogram. Severe left pyelonephritis with coalescensing abscesses and small areas of hemorrhage (notice areas of high density on noncontrast).
Case Discussion
Take some time to review the noncontrast exam - what features would have made you concerned about abscess? Would you recommend a contrast-CT based on that appearance? Did you notice the hemorrhage (high density) on the non contrast series in the left kidney? Renal abscesses frequently start small and coalesce as in this example, and can be difficult to distinguish from the normal parenchyma on non contrast studies, although liver window can sometimes help.