Pseudotumor Xanthogranulomatous Pyelonephritis: Dignaostic and Therapeutic Difficulties (Two Cases)

Abstract

Introduction: Xanthogranulomatous pyelonephritis is a rare and unusual form of chronic pyelonephritis, characterized by the destruction of the renal parenchyma and its replacement by granulomas, abscesses and lipid-laden macrophage collections. Despite clinical and radiological knowledge, it remains a surprise for the surgeon. We are reporting through these two observations the diagnostic difficulties of this condition would lead to an inappropriate treatment as well as to a more severe disease. Observations: Two patients (52 and 57 years old), one of whom is followed fortype 2 diabetes mellitus , were hospitalized for pyonephrosis due to obstructive pyelic and ureteral lithiasis. The pyonephrosis was revealed by a chronic loin pain in a febrile context and confirmed by urogramme showing a destruction of the renal parenchyma, dilated pyelocaliceal cavities with rounded formations of pseudo-tumoral appearance on the lithiasis obstacles. Our initialtreatment consisted of percutaneous nephrostomy under antibiotic covering and secondarily of nephro-ureterectomy without bladder flange performed six weeks later. Histopathology studies showed diffuse xanthogranulomatous pyelonephritis. The postoperative follow up was simple in both cases. Conclusion: Xantogranulomatous pyelonephritis is a rare, severe and chronic form of pyelonephritis whose diagnosis is always histological. Its clinical picture is no specific, hence the problem is that it poses achalleng of differential diagnosis with renal tumors and urogenital tuberculosis. Its treatment is based on nephrectomy.