Presentation
Diabetic. Fever, right flank pain and dysuria. Abnormal urine dipstick.
Patient Data

Large volume of gas in the right retroperitoneum, largely along the medial perinephric space.
No renal tract stones.





Extensive right intraparenchymal and perinephric gas.
Edematous right kidney, with minor prominence of the collecting system. Right perinephric inflammatory change.
No renal tract stones.
Case Discussion
Pneumoretroperitoneum is much less common than pneumoperitoneum.
A less frequent cause is from emphysematous pyelonephritis - especially as profound as on this study.
The patient is nearly always diabetic - an obstructing stone may be the trigger - but not always - as in this case.