Berna Şeker YILMAZ, Serdar CEYLANER, Neslihan ÖNENLİ MUNGAN

Brown Vialetto Van Laere syndrome: presenting with left ventricular non-compaction and mimicking mitochondrial disorders

Background. Brown-Vialetto-Van Laere syndrome (BVVLS) is a rare, treatable neurodegenerative disorder with a variable clinical presentation, caused by mutations in three different riboflavin transporter genes. Case. An 11-year-old-boy presented with respiratory insufficiency and a rapidly progressive muscle weakness. He was the fifth child of a consanguineous marriage with a medical history of hearing loss. He was peripherally week with a reduced muscle tone. Upper extremity muscles were effected more than lower limbs. He deteriorated rapidly and became quadriplegic. Brain magnetic resonance imaging and magnetic resonance spectroscopy were normal. Echocardiography revealed left ventricular non-compaction. A homozygous c.1088C>T (p.363L) missense mutation was identified in SLC52A2 gene. Significant clinical improvement was seen with high dose riboflavin. Conclusion. This is the first reported BVVLS case presented with left ventricle-non compaction which may be caused by a secondary respiratory chain deficiency. Riboflavin transporter deficiencies should be considered in the differential diagnosis of mitochondrial disorders and secondary respiratory chain deficiencies should be thought during the follow-up of BVVLS.

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