Arrhythmia in thiamine responsive megaloblastic anemia syndrome

Özet

Thiamine responsive megaloblastic anemia syndrome (TRMAS) is a rare,autosomal recessive disorder characterized by megaloblastic anemia, diabetesmellitus, and progressive sensorineural deafness. Mutations in the SLC19A2gene that codes for thiamine transporter 1 protein cause TRMAS, and morethan 30 homozygous mutations have been identified to date. Congenital heartdiseases and arrhythmias have been reported in few patients. We presentcardiac features of five patients with TRMAS. Five patients had macrocyticanemia, diabetes mellitus, and sensorineural deafness. Two siblings hadalso optic atrophy. SLC19A2 gene mutation was shown in all patients. Twopatients developed supraventricular tachycardia during an episode of diabeticketoacidosis. Five patients had absent P waves on baseline electrocardiography,and one patient had additional low QRS voltage. None of the patients hadstructural heart disease. Discontinuation of thiamine treatment appears totrigger supraventricular tachycardia episodes at puberty.