Evaluation of Beta 2-Microglobulin, Cystatin C, and Lipocalin-2 as Renal Biomarkers for Patients with Fabry Disease

BACKGROUND: Since renal failure is one of the main causes of death in patients with Fabry disease (FD), renal follow-up is an important part of clinical monitoring in these patients. Despite its known limitations, serum creatinine is still the most widely used biomarker. While new renal biomarkers are described, their effectiveness has not yet been fully evaluated in relation to FD. OBJECTIVES: This study aimed to compare renal biomarkers commonly and rarely used in the evaluation of FD patients. METHOD: The usual biomarkers for renal monitoring (microalbuminuria, proteinuria, and creatinine) and some more rarely used (cystatin C, beta 2-microglobulin [β2M], neutrophil gelatinase-associated lipocalin/lipocalin-2) were quantified in the blood and/or urine samples of 40 FD patients, 39 controls without chronic kidney disease (CKD) paired by age and sex and 38 controls with CKD undergoing hemodialysis. RESULTS: Significant statistical differences (p < 0.05) were observed for cystatin C and lipocalin-2 in plasma levels, for β2M and serum creatinine levels and by estimated glomerular filtration rate when compared FD patients and control group with CKD and for proteinuria and microalbuminuria in urine samples and for lipocalin-2 in plasma levels when compared FD patients and control group without CKD. Urine creatinine (UCreat), pH, and urine specific gravity did not present a significant statistical difference between groups. CONCLUSION: Considering serum creatinine as gold standard, all renal parameters evaluated, including receiver operating characteristic curve, indicated β2M as the best biomarker, followed by cystatin C, proteinuria and microalbuminuria, while the results for lipocalin-2 and UCreat do not indicate good predictors of renal impairment. It suggests that at least 2 altered biomarkers should be considered to characterize a renal alteration, thereby establishing a better therapeutic course for FD patients. If possible, along with serum creatinine, measurement of β2M or cystatin C for renal evaluation of Fabry's patients should be considered.