The frequency of Fabry disease with the E66Q variant in the α-galactosidase A gene in Japanese dialysis patients: a case report and a literature review

Fabry disease (FD) is an X-linked disorder resulting in a deficiency in alpha-galactosidase A (alpha-Gal) activity. FD is one of the causes of progressive renal dysfunction, but its diagnosis is often delayed or missed completely. We herein report the case of a 70-year-old male who had been receiving hemodialysis (HD) for 23 y who was diagnosed with FD after his participation in a screening program for plasma alpha-Gal activity for 892 HD patients. He had a low plasma alpha-Gal activity level and was demonstrated to have an E66Q mutation in exon 2 of the alpha-Gal gene. One of his daughters had the same mutation. The proband died due to aspiration pneumonia before receiving enzyme replacement therapy. We reviewed previous studies and found E66Q mutation in 36% of Japanese FD patients on HD including the present case. The clinical characteristics of E66Q variant are also discussed.