I saw the "bear paw" sign - Massive renal xanthogranulomatous pyelonephritis.

The bear paw sign is a radiologic sign seen on computed tomography (CT) that indicates the development of xanthogranulomatous pyelonephritis (XGP). It refers to the multiple, rim-enhancing, low attenuation renal collections seen in the diffuse form of XGP. The term "bear paw" sign first appeared in the literature in 1989 and has since been widely used to describe this serious, but treatable, pathology.