G11.11 Friedreich ataxia

Name of the Condition

• Friedreich ataxia

Summary

Friedreich ataxia is a genetic disorder characterized by progressive nervous system damage and impaired muscle coordination (ataxia). It typically begins in childhood or adolescence and affects movement, balance, and other bodily functions. The condition results from mutations in the FXN gene, leading to reduced production of frataxin, a protein essential for mitochondrial function.

Causes

Friedreich ataxia is caused by a mutation in the FXN gene, which leads to abnormal expansion of GAA trinucleotide repeats in the gene's first intron. This expansion impairs the production of frataxin, a protein critical for mitochondrial health. The mutation is inherited in an autosomal recessive pattern, meaning an individual must inherit two copies of the mutated gene (one from each parent) to develop the condition.

Risk Factors

• Family history of Friedreich ataxia or related genetic disorders.
• Consanguinity (parents who are closely related).
• Inheritance of two mutated FXN gene copies (autosomal recessive pattern).
• Age (symptoms typically appear before adulthood, often in childhood or adolescence).

Symptoms

• Progressive loss of coordination (ataxia) affecting gait, speech, and limb movements.
• Unsteady walking, frequent falls, or difficulty with balance.
• Slurred speech (dysarthria) or abnormal eye movements (nystagmus).
• Muscle weakness, especially in the limbs.
• Loss of sensation in the extremities (peripheral neuropathy).
• Scoliosis (curvature of the spine) or foot deformities.
• Cardiac issues, such as hypertrophic cardiomyopathy.
• Hearing loss or vision problems in some cases.

Diagnosis

Diagnosis involves a clinical evaluation, including neurological examination to assess coordination and reflexes. Genetic testing confirms the presence of expanded GAA repeats in the FXN gene. Additional tests, such as electromyography (EMG) or cardiac imaging, may be used to evaluate associated symptoms like neuropathy or heart conditions.

Treatment Options

Treatment focuses on managing symptoms and complications. Physical therapy and occupational therapy help maintain mobility and independence. Medications may address cardiac issues, diabetes, or other associated conditions. Orthopedic interventions, such as braces or surgery, can correct spinal deformities. Regular monitoring of cardiac and metabolic health is essential.

Prognosis and Follow-Up

Friedreich ataxia is a progressive condition, and symptoms typically worsen over time. Life expectancy may be reduced, often due to cardiac complications. Regular follow-up with neurologists, cardiologists, and other specialists is important to manage symptoms and address complications. Early intervention can improve quality of life and delay disease progression.

Complications

• Progressive loss of mobility and independence.
• Cardiac complications, including heart failure or arrhythmias.
• Diabetes or glucose intolerance.
• Hearing or vision loss.
• Respiratory issues due to weakened muscles.
• Psychological effects, such as depression or anxiety.

Lifestyle & Prevention

• Engage in regular physical therapy to maintain strength and coordination.
• Use assistive devices, such as walkers or wheelchairs, to improve mobility.
• Monitor and manage cardiac health through regular check-ups.
• Follow a balanced diet and exercise plan to support overall health.
• Avoid activities that increase fall risk, such as contact sports.

When to Seek Professional Help

Seek medical attention if you or a family member experiences unexplained coordination problems, difficulty walking, slurred speech, or other neurological symptoms. Early diagnosis and intervention can help manage the condition and improve outcomes. Prompt care is also needed for cardiac symptoms, such as chest pain or shortness of breath.

Tips for Medical Coders

When coding for Friedreich ataxia, use the ICD-10-CM code G11.11. Ensure documentation supports the diagnosis, including genetic testing results or clinical findings consistent with the condition. Note any associated complications, such as cardiomyopathy or diabetes, as these may require additional codes. Verify that the code aligns with the patient's specific clinical presentation and documented evaluation.