title: Nephron hypertrophy and glomerulosclerosis and their association with kidney function and risk factors among living kidney donors.
abstract: OBJECTIVE
  The relationship of kidney function and CKD risk factors to structural changes in the renal parenchyma of normal adults is unclear. This study assessed whether nephron hypertrophy and nephrosclerosis had similar or different associations with kidney function and risk factors.
  
  
  METHODS
  From 1999 to 2009, 1395 living kidney donors had a core needle biopsy of their donated kidney during transplant surgery. The mean nonsclerotic glomerular volume and glomerular density (globally sclerotic and nonsclerotic) were estimated using the Weibel and Gomez stereologic methods. All tubules were counted in 1 cm(2) of cortex to determine a mean profile tubular area. Nephron hypertrophy was identified by larger glomerular volume, larger profile tubular area, and lower nonsclerotic glomerular density. Nephrosclerosis was identified by higher globally sclerotic glomerular density.
  
  
  RESULTS
  The mean (± SD) age was 44 ± 12 years, 24-hour urine albumin excretion was 5 ± 7 mg, measured GFR was 103 ± 17 ml/min per 1.73 m(2), uric acid was 5.2 ± 1.4 mg/dl, and body mass index was 28 ± 5 kg/m(2). Of the study participants, 43% were men, 11% had hypertension, and 52% had a family history of ESRD. Larger glomerular volume, larger profile tubular area, and lower nonsclerotic glomerular density were correlated. Male sex, higher 24-hour urine albumin excretion, family history of ESRD, and higher body mass index were independently associated with each of these measures of nephron hypertrophy. Higher uric acid, higher GFR, and older age were also independently associated with some of these measures of nephron hypertrophy. Hypertension was not independently associated with measures of nephron hypertrophy. However, hypertension and older age were independently associated with higher globally sclerotic glomerular density.
  
  
  CONCLUSIONS
  Nephron hypertrophy and nephrosclerosis are structural characteristics in normal adults that relate differently to clinical characteristics and may reflect kidney function and risk factors via separate but inter-related pathways.
authors.affiliation: Division of Nephrology and Hypertension.
authors.forename: Hisham E
authors.initials: HE
authors.lastname: Elsherbiny
authors.affiliation: Division of Anatomic Pathology.
authors.forename: Mariam P
authors.initials: MP
authors.lastname: Alexander
authors.affiliation: Division of Biomedical Statistics and Informatics.
authors.forename: Walter K
authors.initials: WK
authors.lastname: Kremers
authors.affiliation: Transplant Center.
authors.forename: Walter D
authors.initials: WD
authors.lastname: Park
authors.affiliation: Department of Nephrology and Hypertension, Cleveland Clinic, Cleveland Ohio.
authors.forename: Emilio D
authors.initials: ED
authors.lastname: Poggio
authors.affiliation: Transplant Center.
authors.forename: Mikel
authors.initials: M
authors.lastname: Prieto
authors.affiliation: Division of Nephrology and Hypertension, Department of Laboratory Medicine and Pathology.
authors.forename: John C
authors.initials: JC
authors.lastname: Lieske
authors.affiliation: Division of Nephrology and Hypertension, Division of Epidemiology, Mayo Clinic, Rochester, Minnesota; and rule.andrew@mayo.edu.
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Rule
mesh_terms: D000328:Adult; D000367:Age Factors; D000419:Albuminuria / Q000652:urine; D015992:Body Mass Index; D005260:Female; D005919:Glomerular Filtration Rate; D005923:Glomerulosclerosis, Focal Segmental / Q000473:pathology* / Q000503:physiopathology*; D006801:Humans; D006973:Hypertension / Q000150:complications; D006984:Hypertrophy; D007676:Kidney Failure, Chronic / Q000235:genetics; D016030:Kidney Transplantation; D019520:Living Donors; D008297:Male; D008875:Middle Aged; D009399:Nephrons / Q000473:pathology*; D012307:Risk Factors; D012737:Sex Factors; D014527:Uric Acid / Q000097:blood
chemical_list: D014527:Uric Acid
keywords: glomerular; glomerulosclerosis; glomerulus; hyperfiltration; nephropathy; renal biopsy