Fax +41 61 306 12 34 E-Mail karger@karger.ch www.karger.com Original Paper Kidney Blood Press Res 2012;35:174–181 DOI: 10.1159/000332083 Renal Function and Solitary Kidney Disease: Wilms Tumour Survivors versus Patients with Unilateral Renal Agenesis Joanna Stefanowicz a Radosław Owczuk b Bogna Kałużyńska d Ewa Aleksandrowicz c Anna Owczarzak c Elżbieta Adamkiewicz-Drożyńska a Anna Balcerska a Departments of a Paediatrics, Haematology, Oncology and Endocrinology, b Anaesthesiology and Intensive Therapy and c Clinical Nutrition and Laboratory Diagnostics, Medical University of Gdansk, and d Paediatric Nephrologic Clinic, Children’s Hospital, Gdansk, Poland hypertension was present in 7/30 (23%) WTs and 1/17 (6%) patients with URA. Conclusions: WTs have similar eGFR to individuals with URA and are more likely to have arterial hy- pertension. The patients with URA have signs of tubular damage. This study demonstrates the need for nephrologi- cal monitoring of individuals with a single kidney. Copyright © 2011 S. Karger AG, Basel Introduction Unilateral functioning solitary kidney involves the absence of one kidney due to unilateral renal agenesis (URA), unilateral atrophic kidney or unilateral nephrec- tomy [1]. Both nephrectomy and congenital solitary kid- ney create a situation in which a single kidney has to take on an additional burden. In nephrectomy, the adaptation is linked with hypertrophy of renal glomeruli and hyper- filtration. In this case, increased glomerular filtration in the remaining nephrons frequently compensates for the sudden loss of functioning renal tissue. Hyperfiltration can be the reason for the progressive sclerosis of glomer- ular vessels and, consequently, decreased efficiency of Key Words Renal function  Solitary kidney  Wilms tumour survivors  Unilateral renal agenesis Abstract Aims: To test the hypothesis that Wilms tumour survivors (WTs) experience increased disturbance in renal function, even after prompt treatment, compared to patients with uni- lateral renal agenesis (URA). Methods: To assess the renal function of 30 WTs and 17 individuals with URA, the estimat- ed glomerular filtration rate (eGFR) was calculated using the Schwartz and Filler formulas as well as the new Schwartz equation for chronic kidney disease. To measure kidney damage, serum levels and urine excretion of  2 -microglob- ulin (B2M), cystatin C (Cys C), neutrophil gelatinase-associat- ed lipocalin (NGAL) were tested, N-acetyl- -glucosamini- dase (NAG), and albumin urine excretion and urine sediment were examined. Blood pressure was measured. Results: No differences were found between the groups in terms of eGFR, serum Cys C, B2M and NGAL concentrations. The urine excretion of Cys C, NGAL and NAG was similar in both groups. URA patients had higher B2M excretion than WTs. Arterial Received: March 3, 2011 Accepted: August 21, 2011 Published online: November 24, 2011 Joanna Stefanowicz, MD, PhD Department of Paediatrics, Haematology, Oncology and Endocrinology Medical University of Gdansk 7 Debinki Street, PL–80952 Gdansk (Poland) Tel. +48 58 349 28 80, E-Mail jstefanowicz  @  gumed.edu.pl © 2011 S. Karger AG, Basel 1420–4096/12/0353–0174$38.00/0 Accessible online at: www.karger.com/kbr