Prognostic associations of clinical and histopathological features in renal amyloidosis

This retrospective study was conducted to assess the relationship between renal functional parameters and histolopathological findings in patients with renal amyloidosis.

A total of 40 patients with biopsy-proven renal amyloidosis, which was diagnosed at the Department of Pathology, Hanyang University Hospital, between 1986 and 2010, were investigated. Renal biopsy specimens were evaluated in various histochemical and immunohistochemical stains using light, immunofluorescence and electron microscopes, and renal function was determined by estimated glomerular filtration rate (eGFR) (ml/min/1.73 m(2)) using the method proposed by the Modification of Diet in Renal Disease study. Glomerular amyloid deposits were classified into four groups: none, mild, segmental and diffuse types. The vascular, tubular and interstitial deposits were subdivided into the negative and positive groups.

In simple regression analysis, 24-hour protein excretion, serum blood urea nitrogen and eGFR were found to significantly correlate with the increased extent of glomerular amyloid deposit. In multiple regression analysis, a decrease in eGFR was significantly associated with an increase in glomerular amyloid deposits (p=0.024), but there was no significant correlation with an increase in 24-hour protein excretion and blood urea nitrogen (p=0.119 and 0.184, respectively).

The results of this study demonstrate that the increased extent of glomerular amyloid deposits may be associated with the decline of GFR in patients with renal amyloidosis.