Biomarcatori di danno renale in pazienti cistinurici: caratterizzazione del metaboloma urinario in una coorte di pazienti con cistinuria

Introduction: Monitoring patients with kidney damage, whether suffering from chronic kidney disease or kidney disorders due to genetic mutations like cystinuria, is traditionally done through the evaluation of parameters such as GFR (estimated glomerular filtration rate, based on age and sex) and the measurement of serum and urinary creatinine levels. However, the use of these parameters provides information only on glomerular function. Therefore, the use of serum and urinary metabolomics is playing an increasingly central role in the development of personalized medicine. Objectives: The aim of this study is to identify abnormal values in the urinary metabolome of cystinuric patients and compare them with the existing literature on the urinary metabolome of patients with chronic kidney disease, as well as with healthy individuals, in order to overcome the current limitations in the clinical management of cystine stone disease and in the prognostic evaluation of kidney failure. Methods: Over a two-year period (2021-2022), we collected a total of 45 urine samples from patients with a confirmed diagnosis of cystinuria, coming from three different kidney stone centers in Italy. Results: The main result obtained in this urinary metabolomics study was the identification of an alteration in the excretion of acylcarnitines and in the mitochondrial oxidation processes of fatty acids, already in the early stages of renal disease in patients affected by cystinuria. Conclusions: The use of urinary metabolomics paves the way for the identification of biomarkers capable of tracking the progression of chronic kidney disease and for identifying new potential therapeutic targets.