Preoperative Renal Volume: A Surrogate Measure for Radical Nephrectomy-Induced Chronic Kidney Disease

• Published in: Journal of endourology Vol. 29; no. 12; p. 1406
• Main Authors: Wu, Fiona Mei Wen, Tay, Melissa Hui Wen, Tai, Bee Choo, Chen, Zhaojin, Tan, Lincoln, Goh, Benjamin Yen Seow, Raman, Lata, Tiong, Ho Yee
• Format: Journal Article
• Language: English
• Published: United States 01.12.2015
• Subjects: Adult; Aged; Carcinoma, Renal Cell - surgery; Disease Progression; Female; Glomerular Filtration Rate - physiology; Humans; Kaplan-Meier Estimate; Kidney - anatomy & histology; Kidney - diagnostic imaging; Kidney Neoplasms - surgery; Male; Middle Aged; Nephrectomy - adverse effects; Organ Size; Postoperative Period; Preoperative Period; Renal Insufficiency, Chronic - diagnosis; Renal Insufficiency, Chronic - etiology; Renal Insufficiency, Chronic - physiopathology; Retrospective Studies; Tomography, X-Ray Computed
• ISSN: 1557-900X
• DOI: 10.1089/end.2015.0318

Surgically induced chronic kidney disease (CKD) has been found to have less impact on survival as well as function when compared to medical causes for CKD. The aim of this study is to evaluate whether preoperative remaining kidney volume correlates with renal function after nephrectomy, which represents an individual's renal reserve before surgically induced CKD. A retrospective review of 75 consecutive patients (29.3% females) who underwent radical nephrectomy (RN) (2000-2010) was performed. Normal side kidney parenchyma, excluding renal vessels and central sinus fat, was manually outlined in each transverse slice of CT image and multiplied by slice thickness to calculate volume. Estimated glomerular filtration rate (eGFR) was determined using the Modification of Diet in Renal Disease equation. CKD is defined as eGFR < 60 mL/min/1.73 m(2). Mean preoperative normal kidney parenchymal volume (mean age 55 [SD 13] years) is 150.7 (SD 36.4) mL. Over median follow-up of 36 months postsurgery, progression to CKD occurred in 42.6% (n = 32) of patients. On multivariable analysis, preoperative eGFR and preoperative renal volume <144 mL are independent predictors for postoperative CKD. On Kaplan-Meier analysis, median time to reach CKD postnephrectomy is 12.7 (range 0.03-43.66) months for renal volume <144 mL but not achieved if renal volume is >144 mL. Normal kidney parenchymal volume and preoperative eGFR are independent predictive factors for postoperative CKD after RN and may represent renal reserve for both surgically and medically induced CKD, respectively. Preoperative remaining kidney volume may be an adjunct representation of renal reserve postsurgery and predict later renal function decline due to perioperative loss of nephrons.