Findings
There are multiple wedge-shaped low-attenuation areas in the left kidney.
Discussion
Wedge-shaped, low attenuation areas may be seen with acute bacterial pyelonephritis or multiple renal infarcts. Location of the wedges in line with the calyces suggests pyelonephritis, wedges located between calyces suggest infarcts. The patient’s clinical presentation also assists in this differential. Complications of the pyelonephritis include renal and perinephric abscess formation, emphysematous pyelonephritis, and pyohydronephrosis.


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