[Xanthogranulomatous pyelonephritis: apropos of 13 cases]

We present 13 patients anatomopathologically diagnosed with xantogranulomatose pyelonephritis. This form of inflammatory reaction may give rise to major pre-operative diagnostic difficulties through being confused with renal neoplasias. Clinical evolution consists of long-developing lithiasis complicated with infection. We regard echography and C.A.T. as extremely useful elements both in accurate pre-operative diagnosis and in the locoregional evaluation of the lesion. Treatment is surgical and the prognosis is favourable.