Multiparametric Magnetic Resonance Imaging (MRI) in Medullary Sponge Kidney

Background : Medullary sponge kidney disease is a congenital disorder caracterised by tubular ectasia and cystic dilatation of the collecting ducts in the pericalyceal region of the renal pyramids, which can lead to nephrolithiasis and frequently associated with impaired tubular function such as distal renal tubular acidosis. The disease knowledge is limited, especially about origin, diagnosis, and physiopathology of the disease. The disease is associated with impaired tubular function such as distal renal tubular acidosis, hypocitraturia, hypercalciuria, which suggest altered kidney medulla function. Multiparametric MRI may provide further informations about the physiopathology and help in earlier diagnosis of the medullary sponge kidney. Objective : The aim of this study is to test the hypothesis that early kidney medulla function alteration in medullary sponge kidney can be detected and characterised with multiparametric MRI. We are expecting to see in medullary sponge kidney a decreased oxygenation content in BOLD MRI (Blood oxygenation level dependent magnetic resonance imaging), and decreased ADC (Apparent diffusion coefficient) value in the medulla. Design : A monocentric prospective case/control study will be conducted in adults with medullary sponge kidney. Controls are adults patients with glomerular filtration rate \> 60 mL/min/1.73m2 without kidney stone attending a renal exploration. After a screening visit, patients included will be evaluated on one day with lithiasis assessment and measurement of glomerular filtration (Urinary collection of the last 24 hours, Urine sample, Blood sample) and they will perform multiparametric magnetic resonance imaging of the kidneys.