Premium
Correlation of Quantitative Digital Image Analysis with the Glomerular Filtration Rate in Chronic Allograft Nephropathy
Author(s) -
Diaz Encarnacion Montserrat M.,
Griffin Matthew D.,
Slezak Jeffrey M.,
Bergstralh Erik J.,
Stegall Mark D.,
Velosa Jorge A.,
Grande Joseph P.
Publication year - 2004
Publication title -
american journal of transplantation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.89
H-Index - 188
eISSN - 1600-6143
pISSN - 1600-6135
DOI - 10.1046/j.1600-6143.2003.00311.x
Subject(s) - sirius red , medicine , renal function , urology , nephropathy , pathology , creatinine , renal biopsy , biopsy , immunoperoxidase , staining , endocrinology , monoclonal antibody , antibody , immunology , diabetes mellitus
Chronic allograft nephropathy (CAN) is characterized by progressive renal functional loss and histologic abnormalities of one or more tissue compartments. In this study, correlations between histologic abnormalities and graft function [glomerular filtration rate (GFR, measured by iothalamate clearance), serum creatinine (S Cr ) and urinary protein ( U Pr )] were investigated using biopsies from 49 patients with newly diagnosed CAN. Extent of tubulointerstitial fibrosis (%TIF), as assessed by a semi‐quantitative score, correlated significantly with GFR, S Cr and U Pr . The close correlation between %TIF and GFR suggested that quantitative measurement of %TIF may predict functional consequences of CAN. Calculation of %TIF by computerized digital analysis was performed using four strategies: (a) quantitation of blue material in Masson's trichrome (MT)‐stained sections, (b) quantitation of red material in Sirius Red‐stained sections (SR‐nonpolarized), (c) quantitation of birefringent material in Sirius Red stained‐sections examined under polarized light (SR‐polarized) and (d) quantification of brown material in sections stained by immunoperoxidase for alpha‐smooth muscle actin. Only the SR‐nonpolarized score correlated significantly with GFR at the time of biopsy‐diagnosis of CAN. We conclude that digital analysis strategies demonstrate variable accuracy in quantifying %TIF. Validation of the SR‐nonpolarized strategy against histologic scoring and GFR supports the application of this technique to longitudinal studies of CAN.