The Clinical Journey of Patients with Riboflavin Transporter Deficiency Type 2

J Child Neurol. 2020 Mar;35(4):283-290. doi: 10.1177/0883073819893159. Epub 2019 Dec 23.

Abstract

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.

Keywords: Brown-Vialetto-van Laere syndrome; SLC52A2; genetic testing; riboflavin transporter deficiency.

MeSH terms

  • Bulbar Palsy, Progressive / complications
  • Bulbar Palsy, Progressive / diagnosis*
  • Bulbar Palsy, Progressive / physiopathology*
  • Child
  • Child, Preschool
  • Delayed Diagnosis / statistics & numerical data*
  • Female
  • Gait Disorders, Neurologic / complications
  • Hearing Loss / complications
  • Hearing Loss / physiopathology
  • Hearing Loss, Sensorineural / complications
  • Hearing Loss, Sensorineural / diagnosis*
  • Hearing Loss, Sensorineural / physiopathology*
  • Humans
  • Male
  • Muscle Weakness / complications
  • Muscle Weakness / physiopathology
  • Optic Atrophy / complications
  • Optic Atrophy / physiopathology
  • Sleep Apnea Syndromes / complications
  • Sleep Apnea Syndromes / physiopathology

Supplementary concepts

  • Brown-Vialetto-Van Laere syndrome