Graft pyelonephritis causing graft failure from de novo AA amyloid

Abstract

A 59-year-old man with end-stage renal failure secondary to autosomal dominant polycystic kidney disease received a renal transplant in 1994. Between 2008 and 2010 he developed recurrent, microbiologically proven episodes of urosepsis associated with a ureteric stricture, which required balloon ureteroplasty, insertion of a JJ stent, and finally a doubleended Memokath. Despite this, graft function continued to decline with nephrotic-range proteinuria, and in 2011 he recommenced hemodialysis. Ongoing episodes of urosepsis necessitated graft nephrectomy. The septic episodes subsequently abated and inflammatory markers normalized. Histology of the kidney revealed scarring and an accumulation of eosinophilic material in the glomeruli and vessel walls, which stained positive for Congo red (Figure 1a and b). Immunohistochemisty for AA amyloid was positive. It appears that AA amyloid deposition resulting from chronic graft pyelonephritis was the cause of this patient’s nephrotic-range proteinuria and, ultimately, graft failure. There have been very few case reports of de novo AA amyloid in renal allografts, and in these cases it has occurred in patients with chronic infective or inflammatory conditions that were present before transplantation. To our knowledge, this is the first case of de novo AA amyloid in a transplanted kidney not associated with a pre-existing chronic inflammatory or immune disorder. http://www.kidney-international.org n e p h r o l o g y i m a g e