Bilateral diffuse xanthogranulomatous pyelonephritis in end-stage renal disease (ESRD)

Xanthogranulomatous pyelonephritis (XGP) is a very rare form of kidney disease characterized by destruction of renal parenchyma, its fibrosis, and its replacement by lipid-laden macrophages. ¹,².

We describe a case of a 46-year-old woman with bilateral staghorn stones and end-stage renal disease (ESRD) under renal replacement therapy by hemodialysis. An abdominal CT scan suggested bilateral XGP (Figure 1) and she was submitted to bilateral nephrectomy. Histopathological analysis confirmed the diagnosis.

Complications in XGP can occur, such as cortical atrophy, abscesses, and kidney loss. The treatment of choice is total nephrectomy, and tumors and granulomatous diseases should be included in the differential diagnosis³-⁵.

Figure 1
CT scan showing the “bear paw sign” in both kidneys (a) and staghorn stones with bilateral hydronephrosis (b). Gross pathological examination showing bilateral cystic formations, abscesses, and fibrosis with architectural distortion of the renal parenchyma (c). Optical microscopy showing numerous macrophages, some with xanthomized aspect (d) and renal parenchyma with focus of histiocytic reaction and areas of necrosis (e).

References

• ¹
  Chuang CK, Lai MK, Chang PL, et al. Xanthogranulomatous pyelonephritis: experience in 36 cases.J Urol. 1992;147:333-336.
• ²
  Parsons MA, Harris SC, Longstaff AJ, Grainger RG. Xanthogranulomatous pyelonephritis: a pathological, clinical, and etiological analysis of 87cases. Diagn Histopathol.1983; 6:203-219.
• ³
  Kuo C, Wu C, Huang C, et al. Xanthogranulomatous pyelonephritis: critical analysis of 30 patients. Int Urol Nephrol. 2011; 43:15-22. doi:10.1007/s11255- 010-9778-8.
  » https://doi.org/10.1007/s11255-
• ⁴
  Ramboer K, Oyen R, Verellen S, et al.Focal Xanthogranulomatous pyelonephritis mimicking a renal tumor: CT- and MR findings and evolution under therapy. Nephrol Dial Transp. 1997; 12: 1028-1030.
• ⁵
  Guzzo TJ, Bivalacqua TJ, Pierorazio PM, et al. Xanthogranulomatous pyelonephritis: presentation and treatment in the laparoscopy era. BJU Int. 2009; 104: 1265.

Publication Dates

• Publication in this collection
  28 May 2021
• Date of issue
  Jul-Sep 2021

History

• Received
  12 Nov 2020
• Accepted
  18 Apr 2021