Systemic Amyloid A Amyloidosis Secondary to Xanthogranulomatous Pyelonephritis.

The combination of systemic amyloid A (AA) amyloidosis and xanthogranulomatous pyelonephritis (XGP) resulting from a chronic urinary tract infection is extremely rare. We herein report a case of systemic AA amyloidosis secondary to XGP for which clinical remission developed after nephrectomy. To our knowledge, this is the first case report describing the clinical improvement of systemic AA amyloidosis secondary to XGP after nephrectomy in Japan. Clinicians should be aware of this uncommon combination and search for amyloid depositions in cases of XGP.