Late-onset and acute presentation of Brown-Vialetto-Van Laere syndrome in a Brazilian family

Abstract

Riboflavin transporter deficiency (formerly known as Brown-Vialetto-Van Laere [BVVL] or Fazio-Londe syndrome) is a neurodegenerative disorder characterized by progressive bulbar palsy with sensorineural deafness or bulbar hereditary neuropathy.1 It is caused by mutations in the riboflavin transporter genes SLC52A2 (RFVT2) or SLC52A3 (RFVT3).2,3 It is a rare syndrome with approximately 70 cases reported worldwide, with molecular diagnoses of RFVT2 or RFVT3.1,4 We have previously described the first Brazilian family with a clinical diagnosis of BVVL.5 In this report, we extend the clinical spectrum associated with this family and describe a new mutation related to the metabolism of riboflavin.