Targeted Screening of Fabry Disease in Male Hemodialysis Patients in Brazil Highlights Importance of Family Screening.

INTRODUCTION

Fabry disease (FD) is a lysosomal storage disorder caused by enzyme α galactosidase A (α-Gal A) deficiency due to mutations in the galactosidase alpha (GLA) gene. It leads to damage several organs, such as the kidneys, due to progressive accumulation of glycosphingolipids.

OBJECTIVE

To estimate the prevalence of FD among male hemodialysis (HD) patients in a northern state of Brazil.

METHODS

Screening was performed using a dried blood spot on filter paper to identify patients with low α-Gal A enzyme activity (≤2.2 µmol/l/h). Those with low enzyme activity underwent genetic analysis of the GLA gene. Family screening was conducted in the index cases.

RESULTS

2,583 male HD patients (age: 52 (18-91 years)) were screened. The α-Gal A assay identified 72 males (2.78%) with low enzyme activity. Genotyping identified 3 patients with GLA mutations: W204X, A368T, both previously reported; and C52F, a novel missense mutation. Only the patient with W204X mutation had classic FD. The prevalence rate was 0.12%. Family screening of the index cases identified 23 family members with the same mutations.

CONCLUSIONS

The prevalence of FD amongst male HD patients found in the Northern of Brazil was low (0.12%). However, family screening of the 3 index cases identified family members at an early stage of the disease, which may benefit from earlier treatment.