New Variant of MELAS Syndrome With Executive Dysfunction, Heteroplasmic Point Mutation in the Gene (m.12015T>C; p.Leu419Pro) and Comorbid Polyglandular Autoimmune Syndrome Type 2

New Variant of MELAS Syndrome With Executive Dysfunction, Heteroplasmic Point Mutation in the Gene (m.12015T>C; p.Leu419Pro) and Comorbid Polyglandular Autoimmune Syndrome Type 2