title: Compensatory Hypertrophy After Living Donor Nephrectomy.
abstract: BACKGROUND
  Previous studies have shown that kidney volume enhances the estimation of glomerular filtration rate (eGFR) in kidney donors. This study aimed to describe the phenomenon of compensatory hypertrophy after donor nephrectomy as measured on computerized tomographic (CT) scans.
  
  
  METHODS
  An institutional Domain Specific Review Board (DSRB)-approved study involved approaching kidney donors to have a follow up CT scan from 6 months to 1 year after surgery; 29 patients participated; 55% were female. Clinical chart review was performed, and the patient's remaining kidney volume was measured before and after surgery based on CT scans. eGFR was determined with the use of the Modification of Diet in Renal Disease equation.
  
  
  RESULTS
  Mean parenchymal volume of the remaining kidney for this population (mean age, 44.3 ± 8.5 y) was 204.7 ± 82.5 cc before surgery and 250.5 ± 113.3 cc after donor nephrectomy. Compensatory hypertrophy occurred in 79.3% of patients (n = 23). Mean increase in remaining kidney volume was 22.4 ± 23.2% after donor nephrectomy in healthy individuals. Over a median follow-up of 52.9 ± 19.8 months, mean eGFR was 68.9 ± 12.4 mL/min/1.73 m(2), with 24.1% of patients (n = 7) in chronic kidney disease grade 3. Absolute and relative change in kidney volume was not associated with sex, race, surgical approach, or background of hypertension (P = NS). There was a trend of decreased hypertrophy with increasing age (P = .5; Spearman correlation, -0.12).
  
  
  CONCLUSIONS
  In healthy kidney donors, compensatory hypertrophy of the remaining kidney occurs in 79.3% of the patients, with an average increment of about 22.4%. Older patients may have a blunted compensatory hypertrophy response after surgery.
authors.affiliation: Department of Urology, National University Health System, Singapore.
authors.forename: K W
authors.initials: KW
authors.lastname: Chen
authors.affiliation: Department of Urology, National University Health System, Singapore.
authors.forename: M W F
authors.initials: MW
authors.lastname: Wu
authors.affiliation: Investigational Medicine Unit, National University Health System, Singapore.
authors.forename: Z
authors.initials: Z
authors.lastname: Chen
authors.affiliation: Saw Swee Hock School of Public Health, National University of Singapore and National University Health System, Singapore; Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, Singapore.
authors.forename: B C
authors.initials: BC
authors.lastname: Tai
authors.affiliation: Department of Urology, National University Health System, Singapore.
authors.forename: Y S B
authors.initials: YS
authors.lastname: Goh
authors.affiliation: Department of Urology, National University Health System, Singapore.
authors.forename: R
authors.initials: R
authors.lastname: Lata
authors.affiliation: National University Centre for Organ Transplantation, National University Health System, Singapore.
authors.forename: A
authors.initials: A
authors.lastname: Vathsala
authors.affiliation: Department of Urology, National University Health System, Singapore. Electronic address: cfsthy@nus.edu.sg.
authors.forename: H Y
authors.initials: HY
authors.lastname: Tiong
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology; D000328:Adult; D000367:Age Factors; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D006984:Hypertrophy / Q000000981:diagnostic imaging* / Q000209:etiology; D007668:Kidney / Q000000981:diagnostic imaging / Q000503:physiopathology; D007680:Kidney Neoplasms / Q000601:surgery; D016030:Kidney Transplantation / Q000379:methods; D019520:Living Donors; D008297:Male; D008875:Middle Aged; D009392:Nephrectomy / Q000009:adverse effects* / Q000379:methods; D051436:Renal Insufficiency, Chronic / Q000601:surgery; D012189:Retrospective Studies; D020858:Tissue and Organ Harvesting / Q000009:adverse effects* / Q000379:methods; D014057:Tomography, X-Ray Computed / Q000379:methods*