Generalized amyloidosis secondary to xanthogranulomatous pyelonephritis.

Unilateral nephrectomy in an 8-year-old male with chronic renal failure and urosepsis revealed a combined histologic lesion of xanthogranulomatous pyelonephritis and amyloidosis. Amyloid deposits were found also in the rectum and liver. On clinical grounds xanthogranulomatous pyelonephritis was also suspected in the remaining kidney. Common causes of systemic amyloidosis were excluded. After operation the signs of amyloidosis diminished, probably due to removal of the infected kidney, but renal function deteriorated rapidly.