Long-Term Survival in Brown-Vialetto-Van Laere Syndrome: A Case Report Highlighting Respiratory Care

Brown-Vialetto-Van Laere syndrome (BVVLS) is an extremely rare genetic neurological disorder caused by riboflavin transport deficiency, an autosomal recessive condition mostly associated with mutations in the SLC52A2 and SLC52A3 genes. It follows a progressive course, typically characterized by sensorineural deafness, facial weakness, ponto-bulbar palsy, ataxia, and peripheral sensory-motor neuropathy. This disease is often associated with childhood mortality if left untreated. We report the case of a 68-year-old woman who first noticed a mild hearing loss at the age of 12. This was followed by a slowly progressive onset of bilateral facial paresis, dysarthro-dysphonia, stridor, and tongue atrophy with fasciculations. At 63 years of age, genetic testing revealed a single heterozygous variant in the SLC52A3 gene. Although typically autosomal recessive, some individuals with classic symptoms and even response to riboflavin therapy have been found to carry only a single mutation in either the SLC52A2 or SLC52A3 gene. Therefore, given the compatible clinical presentation, a diagnosis of BVVLS was considered after discussion with a center of expertise. Consequently, 10 mg/kg/day of riboflavin supplementation was prescribed for three years, but no significant clinical improvement was observed. Currently, at age 68, the patient is on nocturnal non-invasive mechanical ventilation (NIV) and uses assisted airway clearance techniques, including air-stacking maneuvers and mechanical insufflation-exsufflation on demand, due to respiratory compromise secondary to diaphragmatic weakness and vocal cord paralysis. This unique presentation of slowly progressive symptoms and long survival may be related to the single heterozygous SLC52A3 variant found. Respiratory care in BVVLS is currently adapted from other neuromuscular disorders with stronger evidence bases. This case highlights the critical role of pulmonology in BVVLS care, including clinical and functional monitoring, early initiation of NIV, and the implementation of airway clearance techniques.