Friedreich Ataxia

Snapshot

  • A 23 year old male with a past medical history of diabetes mellitus presents with muscle weakness, staggering gait with frequent falling, dysarthria and a curvature in his upper spine.  On physical exam the patient is noted to have marked muscle weakness (2/5 in upper and lower extremitites), a loss of deep tendon reflexes, nystagmus as well as pes cavus and kyphoscoliosis.  Patient had a recent ED visit for pneumonia and a bedside ultrasound demonstrated a hypertrophic cardiomyopathy.

Introduction

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  • Congenital impairment of mitochondrial function leading to cerebellar and spinal cord degeneration
    • due to a mutation in the frataxin gene which is essential for mitochondrial iron regulation
  • Presents in childhood
  • Autosomal recessive  
  • trinucleotide repeat disorder (GAA) on chromosome 9 

Presentation

  • Symptoms 
    • staggering gait
    • frequent falling 
    • wheelchair bound by first decade
    • insulin resistance
    • dysarthria
  • Physical exam
    • nystagmus
    • neurological sequelae
      • decreased vibratory and proprioceptive senses
      • muscle weakness
      • loss of deep tendon reflexes
    • musculoskeletal deformities 
      • pes cavus
      • hammer toes
  • kyphoscholiosis

Prognosis and Complications

  • Death in adolescence most commonly due to cardiac arrhythmia
    • a sequlae of hypertrophic cardiomyopathy