[1374] Non-Functioning Glomeruli as a Marker of Renal Damage

JR Jenkins, SV Brodsky, A Satoskar, G Nadasdy, T Nadasdy. The Ohio State University Medical Center, Columbus, OH

Background: It is well-established that the degree of interstitial fibrosis (IF) correlates better with renal function than the percentage of sclerotic/obsolescent glomeruli. However, non-functioning glomeruli include not only sclerotic glomeruli but also glomeruli with obvious periglomerular fibrosis (PF). Glomeruli with PF are frequently atubular or are connected to severely atrophic tubules and most likely do not contribute to glomerular filtration. The aim of our study was to examine the correlation between the number of non-functioning glomeruli (sclerotic and those with PF) with renal function and with the degree of interstitial fibrosis.
Design: A total of 114 native kidney biopsies taken from patients with chronic renal diseases were examined and assessed for the percentage of interstitial fibrosis in the renal cortex and the number of non-functioning glomeruli. Findings were correlated with the serum creatinine level at the time of biopsy. Biopsies with any acute/active pathologic change and biopsies from patients with acute renal failure were not included in the study. The biopsies were then subdivided into two groups: 1) with diabetic nephropathy (n = 45) and 2) without diabetic nephropathy (n = 69).
Results: The percentage of sclerotic glomeruli did not correlate with IF (R sq.=0.0017, p = 0.6574), but the percentage of non-functioning glomeruli strongly correlated with the percentage of IF (R sq.=0.4443, p<0.0001).

The degree of IF positively correlated with serum creatinine levels (R sq.=0.4582, p<0.0001). In our study, the percentage of non-functioning glomeruli correlated better with serum creatinine (R sq.=0.2817, p<0.0001) than did the percentage of sclerotic glomeruli with serum creatinine (R sq.=0.2528, p<0.0001). This was particularly true in patients with diabetic nephropathy (R sq.=0.3973, p<0.0001).
Conclusions: The percentage of non-functional glomeruli (sclerotic glomeruli and glomeruli with PF) in a renal biopsy specimen provides a better estimate of chronic renal damage and renal function than the percentage of sclerotic glomeruli only. Therefore, the number of glomeruli with periglomerular fibrosis should be routinely included in the microscopic analysis of renal biopsies.
Category: Kidney (does not include tumors)

Monday, March 9, 2009 9:30 AM

Poster Session I Stowell-Orbison/Autopsy Award # 201, Monday Morning