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What is Bear paw sign is seen in and explain in detail?
Xanthogranulomatous pyelonephritis (XGP): Rare form of chronic pyelonephritis and represents a chronic granulomatous disease resulting in a non-functioning kidney. Radiographic features are usually specific. CT findings are most helpful in reaching the correct diagnosis. The normal renal outline is lost and enlarged with a paradoxical contracted renal pelvis. The calyces, in contrast, are dilated giving a multiloculated appearance that has been likened to the Paw print of a bear (bear's paw sign). Sometimes there is a perinephric extension with thickening of Gerota's fascia. Calcification can be better delineated on CT scan. Bear paw sign in xanthogranulomatous pyelonepritis. Bear claw sign is seen in liver trauma on CECT.