High-risk screening for Fabry disease in a Canadian cohort of chronic kidney disease patients

Background: Fabry disease is an X-linked lysosomal storage disorder with a highly heterogeneous clinical presentation. This complex disease is caused by a deficient activity of the enzyme alpha-galactosidase A, which is involved in the catabolism of glycosphingolipids. The prevalence of Fabry disease is underestimated, due to the presence of atypical variants. High-risk screening protocols are particularly relevant for this disease due to the availability of treatments, such as enzyme replacement and chaperone therapies. As kidney manifestations are present in the majority of male and many female patients with Fabry disease, a high-risk screening protocol was performed for patients with chronic kidney disease of unknown etiology. Methods: Recruitment of 397 participants took place in four centers across Canada from 2011 to 2017. Globotriaosylceramide (Gb(3)) was analyzed in dried urine spots by liquid chromatography/tandem mass spectrometry followed by globotriaosylsphingosine (lyso-Gb(3)) on the repeat analysis. Results: The collection and shipment of urine specimens on filter paper resulted in easier handling/shipment and significant cost-saving. No Fabry patients were detected in this study. Conclusions: Increased concentrations of urinary Gb(3) were observed in 13.6% of patients with chronic kidney disease suggesting that chronic kidney disease or other comorbidities might be associated with increased urinary Gb(3) concentrations.