Friedreich Ataxia (FDRA)

What is Friedreich Ataxia (FDRA) according to the summary?

An autosomal recessive disorder involving trinucleotide repeat expansion that leads to progressive neurodegeneration. Summary 1

What parts of the nervous system are primarily affected in Friedreich Ataxia, and what does this cause?

It affects multiple spinal cord tracts, causing muscle weakness and impaired coordination of all limbs. Summary 2

What is the main resulting symptom of Friedreich Ataxia in childhood?

A staggering gait. Summary 3

Besides neurological symptoms, what other features are characteristic of Friedreich Ataxia?

Skeletal abnormalities, cardiomyopathy, and diabetes. Summary 4

What primarily determines the clinical course of Friedreich Ataxia?

The extent of the loss of mobility and cardiac involvement. Summary 5

How is a diagnosis of Friedreich Ataxia confirmed?

Confirmation with genetic tests. Summary / Dx 6

What is the prognosis for Friedreich Ataxia given there is no curative therapy?

The prognosis is poor. Summary / Prog 7

How common is Friedreich Ataxia among autosomal recessive ataxias?

It is the most common autosomal recessive ataxia. Epidemiology 8

What is the peak incidence age range for Friedreich Ataxia?

8-15 years (most cases < 25 years). Epidemiology 9

Which population is most affected by Friedreich Ataxia?

Individuals of Central and Northern European descent. Epidemiology 10

What is the genetic cause of Friedreich Ataxia?

Trinucleotide repeat expansion (of GAA) in the FXN gene on chromosome 9. Etiology 11

What protein is deficient in Friedreich Ataxia due to the FXN gene mutation?

Frataxin (an iron-binding protein). Etiology 12

What is the pathophysiological consequence of frataxin deficiency in Friedreich Ataxia?

Intramitochondrial accumulation of iron and dysregulation of cellular antioxidant defense due to mitochondrial dysfunction, leading to oxidative damage and degeneration of CNS/PNS. Etiology / Patho 13

What is a common presenting neurological feature of Friedreich Ataxia due to spinocerebellar tract damage?

Progressive ataxia (impaired coordination of muscles) of all limbs. Clinical 14

Describe the gait ataxia seen in Friedreich Ataxia.

Bilateral lower limbs equally affected; wide-based gait with frequent falling; titubation while standing or sitting. Clinical 15

What type of tremors are seen in the arms in Friedreich Ataxia?

Action and intention tremors. Clinical 16

What sensory modalities are impaired in Friedreich Ataxia due to dorsal column damage?

Impaired proprioception and vibration sense (pallhypesthesia). Clinical 17

What happens to deep tendon reflexes in Friedreich Ataxia, and why?

Loss of deep tendon reflexes due to degeneration of the dorsal root ganglia. Clinical 18

What type of paralysis can occur in Friedreich Ataxia due to lateral corticospinal tract degeneration?

Spastic paralysis. Clinical 19

List three other neurological symptoms (besides ataxia, sensory loss, reflex changes, spasticity) in Friedreich Ataxia.

Nystagmus, dysarthria, dysphagia (may have uncoordinated breathing), bladder dysfunction, hearing loss. (Any 3) Clinical 20

What skeletal deformities are common in Friedreich Ataxia?

Secondary scoliosis (kyphoscoliosis), usually in childhood; foot deformity (talipes equinovarus, pes cavus with hammertoes). Clinical 21

What cardiac condition is a significant feature of Friedreich Ataxia?

Concentric hypertrophic cardiomyopathy, causing palpitations, arrhythmias, dyspnea, exercise intolerance. Clinical 22

What endocrine disorder is associated with Friedreich Ataxia?

Diabetes mellitus. Clinical 23

What does the mnemonic "FRiedreich ATAXia" highlight about the condition?

Individuals have ATAXic GAAit due to the expansion of the triplet GAA in the FRATAXin gene. Clinical 24

What specific diagnostic test should be performed in all suspected cases of Friedreich Ataxia?

A specific trinucleotide repeat expansion assay (for GAA repeats in FXN gene). Diagnosis 25

What are typical ECG findings in Friedreich Ataxia?

T-wave inversion and ventricular hypertrophy. Diagnosis 26

What does echocardiography typically show in Friedreich Ataxia?

Symmetric, concentric ventricular hypertrophy. Diagnosis 27

What are the findings on sensory nerve conduction studies in Friedreich Ataxia?

Absent or reduced sensory nerve action potentials (SNAP). Diagnosis 28

What are the findings on MRI of the brain and spinal cord in Friedreich Ataxia?

Cervical spine atrophy (minimal cerebellar atrophy). Diagnosis 29

Is there a curative treatment available for Friedreich Ataxia?

No, there is no curative treatment available. Treatment 30

What does supportive care for Friedreich Ataxia involve?

Multidisciplinary approach: genetic counseling, physiotherapy, and speech and language therapy. Treatment of cardiologic, orthopedic, and metabolic (diabetes) features. Treatment 31

By what age do individuals with Friedreich Ataxia commonly become nonambulatory?

By age 20-30. Prognosis 32

What is the average age at death for individuals with Friedreich Ataxia?

37 years. Prognosis 33

What is the most common cause of death in Friedreich Ataxia?

Heart failure due to hypertrophic cardiomyopathy. Prognosis 34

What preventative measures can be taken regarding Friedreich Ataxia?

Carrier testing of relatives; prenatal testing (genetic counseling recommended for parents with one affected child). Prevention 35