| Classification |
CT findings |
Recommended management |
| Class I |
gas limited to the collecting system |
medical management alone or medical management combined with percutaneous drainage |
| Class II |
gas limited to the renal parenchyma alone
|
| Class IIIA |
perinephric extension of gas or abscess |
medical management plus percutaneous drainage, non-responders in this group required nephrectomy |
| Class IIIB |
Extension of gas beyond the Gerota fascia |
| Class IV |
EPN in a solitary kidney or bilateral EPN |
