Fabry disease in the era of enzyme replacement therapy: a renal perspective

A Rare Cause of Young Stroke: What Rheumatologists Should Know about Fabry Disease

Systemic vasculitis is a category of autoinflammatory diseases usually involving multiple organs. Involvement of the central nervous system (CNS) may mimic other disorders, hence resulting in overdiagnosis. This is a case report of a young man who presented with acrodynia, episodic pyrexia, and recurrent strokes. He was treated for systemic vasculitis with glucocorticoids and immunosuppressants, which failed to prevent the stroke. Finally, Fabry disease was diagnosed after [Formula: see text]-galactosidase A gene mutation analysis was done. Rheumatologists should be aware of Fabry disease, which may present with multi-system involvement that mimics vasculitis. To avoid inappropriate treatment, a comprehensive differential diagnosis should be considered before a diagnosis of primary systemic vasculitis is made. Recurrent strokes, especially in males younger than 40, should raise suspicions of Fabry disease.

Successful Combined Heart and Kidney Transplantation in Patient With Fabry's Disease: A Case Report

Fabry's disease is a X-linked hereditary disease that causes the accumulation of glycosphingolipids in tissues and organs, including the kidneys and heart. This can result in both chronic kidney disease and cardiac dysfunction, including arrhythmias and heart failure. We describe a case of a 62-year-old male with Fabry's disease undergoing successful combined heart and kidney transplantation for chronic renal failure and low-output systolic heart failure. The patient has normal cardiac function and normal renal function 7 years after transplantation, while being maintained on enzyme replacement therapy with recombinant human alpha-galactosidase A. Fabry's disease is not a contraindication for organ transplantation, even in patients presenting with both renal failure and heart failure.

Non-invasive high-risk screening for Fabry disease hemizygotes and heterozygotes

The most appropriate time for screening for Fabry disease (FD) is school age. For this reason, we developed non-invasive methods for measuring urinary alpha-galactosidase A (alpha-gal A) protein, using enzyme-linked immunosorbent assay (ELISA), and for globotriaosylceramide (GL-3), using tandem mass spectrometry (MS/MS). We measured these two biomarkers in the urine of previously diagnosed FD hemizygotes and heterozygotes, and in controls. All the classic FD hemizygotes were clearly distinguished from controls by either method alone, and combining the two assays produced 96% sensitivity for detecting heterozygotes. To assess the utility of these methods for screening school children and adults at high risk of FD, a pilot study was conducted. To distinguish FD from 432 controls, cut-off values for alpha-gal A protein and GL-3 were set at the 5th and 95th centile values of the controls, respectively. Among the high-risk patients, the measurements exceeded the cut-off values for both biomarkers in male and female subjects and were strong indicators for Fabry hemizygotes and heterozygotes. However, we recommend that if the results of the first measurements exceed the cut-off values for only one of these biomarkers, another urine sample should be requested for re-assay to confirm the result.

Kidney Transplantation Improves Survival and Is Indicated in Fabry’s Disease

BACKGROUND

Fabry's disease (FD) is an inborn error of glycosphingolipid catabolism with progressive systemic deposition of globotriaosylceramide thereby leading to renal and cardiac failure. Current therapy involves symptomatic medical management, dialysis, enzyme replacement therapy, kidney transplantation (KTx), and more recently gene therapy. Case fatalities occur in the fourth decade of life resulting from uremia unless dialysis or KTx is undertaken.

STUDY DESIGN

This is a retrospective study aimed at determining the effect of KTx on the long-term outcome of patients with FD.

RESULTS

Between 1964 and 1998, ten patients with FD received KTx at our institutions. Actuarial patient and graft survivals were 100% and 90% at 5 years; 76% and 66% at 10 years. One kidney graft was lost due to rejection. Patient survival data compared favorably at 5 years with survival of FD patients on hemodialysis alone (41%, P < .05). Five patients are alive at the time of this study, and five patients died with median survival time after KTx of 128 months (range: 74-160 months).

CONCLUSIONS

This study demonstrates an excellent outcome in patients with FD in the first decade after KTx. In the absence of a severe contraindication, we advocate KTx to improve the overall prognosis of patients with renal failure due to FD. Based on the data, enzyme replacement therapy after KTx seems indicated, as FD progresses posttransplant, leading to case fatalities in the second decade after KTx.