The Clinical Journey of Patients with Riboflavin Transporter Deficiency Type 2

Purpose: To identify symptoms and health care interactions with patients with riboflavin transporter deficiency (RTD) type 2 prior to diagnosis. Methods: Parents of children with riboflavin transporter deficiency type 2 (n = 10) were interviewed to collect data on the patient’s clinical journey. Results: The average diagnostic delay was 27.6 months. Neurologists were the most commonly visited clinician (90%). Common symptoms during the first year of the patient’s clinical journey included abnormal gait and/or ataxia (70%), nystagmus (50%), and upper body muscle weakness (40%). Prior to diagnosis, optic atrophy, sleep apnea, breath-holding spells, and dysphagia were commonly observed. Hearing loss was only reported in 40% of subjects prior to diagnosis. Riboflavin responsive megaloblastic anemia is reported for the first time. Mitochondrial disease was the most common suspected diagnosis (30%). Conclusion: Despite clinical variability, common early symptoms of riboflavin transporter deficiency type 2 exist that can better allow clinicians to more rapidly identify riboflavin transporter deficiency type 2.