Xanthogranulomatous Pyelonephritis

Abstract

Xanthogranulomatous pyelonephritis (XGP) is grouped as chronic pyelonephritis that showed kidney enlargement resembling a neoplasm, therefore, it is called pseudotumor. XGP causes destruction of the kidney, disturbance of renal function, and an invasion of infection of renal parenchyme into perinephric adipose tissues and peritoneum. Preoperatively, it is often suspected as a renal cell carcinoma. XGP is occurred rarely, it accounts only 1% of all kidney infection. It can be seen in all ages, but more frequently in middle age female and elderly. The main cause of XGP is chronic obstruction and infection of Proteus or E. Coli. Microscopically, the characteristic feature is the existence of lipid-laden foamy macrophages. A surgery is the first choice and the prognosis is better in unilateral infection cases. We reported a 30-year-old female with a clinical diagnosis of ovarial cyst. Post-operative tissue was found in cystic form tissue. Microscopical examination showed a pyelonephritis and foci of lipid-laden foamy macrohages. It was concluded as an XGP case. The XGP case in female 30 years old is very rare. In this case, the causes of XGP were chronic obstruction and infection. The destructed kidney showed a cystic form that looked like an obstructive hydronephrosis.

Clinicopathological spectrum of xanthogranulomatous pyelonephritis

“…The histomorphologic differentials include renal cell carcinoma with sarcomatoid features, leiomyosarcoma, Wilm's tumor, lymphoma, malakoplakia, megalocytic interstitial nephritis, pyelonephritis, tuberculosis, and perinephric abscess. [23829] The benign entities, malakoplakia and megalocytic interstitial nephritis, can be excluded by observing cytoplasmic periodic acid Schiff-positive, diastase-resistant material in the histiocytes. Michaelis–Gutmann bodies are characteristically seen in malakoplakia.…”

“…The main cause of XGP is chronic obstruction and infection. [2] The condition is usually unilateral and results in a nonfunctioning kidney. [3]…”

Xanthogranulomatous pyelonephritis with calculus migration into the psoas abscess: an unusual complication

“…It is more frequently seen in middle-age females, and elderly. 1,2 However, it has also been reported to occur in neonates. Patients usually present with abdominal pain, pyrexia, burning micturition, hematuria.…”