Association of Kidney Function and Metabolic Risk Factors With Density of Glomeruli on Renal Biopsy Samples From Living Donors

• Published in: Mayo Clinic proceedings 2011-04, Vol.86 (4), p.282-290
• Main Authors: Rule, Andrew D., MD, MSc, Semret, Merfake H., MD, Amer, Hatem, MD, Cornell, Lynn D., MD, Taler, Sandra J., MD, Lieske, John C., MD, Melton, L. Joseph, MD, Stegall, Mark D., MD, Textor, Stephen C., MD, Kremers, Walter K., PhD, Lerman, Lilach O., MD, PhD
• Format: Article
• Language: English
• Subjects: Adult; Age Factors; Biological and medical sciences; Biopsy; Blood Pressure - physiology; Care and treatment; Cell Count; Female; General aspects; Glomerular Filtration Rate - physiology; Glomerulonephritis; Glomerulonephritis - pathology; Humans; Internal Medicine; Kidney Glomerulus - cytology; Kidney Glomerulus - pathology; Kidney Glomerulus - physiology; Kidney Transplantation - physiology; Kidneys; Living Donors; Male; Medical sciences; Metabolic Syndrome - epidemiology; Metabolic Syndrome - physiopathology; Middle Aged; Original; Risk Factors; Transplantation; Transplantation, Homologous
• ISSN: 0025-6196; 1942-5546
• DOI: 10.4065/mcp.2010.0821

OBJECTIVE To test the hypothesis that kidney function and metabolic risk factors are associated with glomerular density on renal biopsy samples from healthy adults. PATIENTS AND METHODS This study compared glomerular density with predonation kidney function, blood pressure, and metabolic risk factors in living kidney donors at Mayo Clinic in Rochester, MN, from May 10, 1999, to February 4, 2009. During implantation of the kidney allograft, an 18-gauge core needle biopsy sample of the renal cortex was obtained, sectioned, and examined by pathologists. Glomerular density was determined by the number of glomeruli (normal and sclerotic) divided by area of cortex. RESULTS The study sample of 1046 kidney donors had a mean of 21 glomeruli (0.8 sclerotic glomeruli) and a glomerular density of 2.3 glomeruli per square millimeter. In a subset of 54 donors, glomerular density inversely correlated with the mean glomerular area (rs =−0.28). Independent predictors of decreased glomerular density were older age, increased glomerular filtration rate, family history of end-stage renal disease, increased serum uric acid, and increased body mass index. Increased urine albumin excretion, hypertension, decreased high-density lipoprotein cholesterol, and metabolic syndrome were also associated with decreased glomerular density after age-sex adjustment. These associations were not explained by the presence of glomerulosclerosis, tubular atrophy, interstitial fibrosis, or arteriosclerosis on the renal biopsy sample. In older donors, decreased glomerular density was attenuated by an increased prevalence of glomerulosclerosis and tubular atrophy. CONCLUSION Decreased glomerular density is associated with many different kidney function and metabolic risk factors among relatively healthy adults and may represent an early state of increased risk of parenchymal injury.