Condition Lookup
Sub-Category:
Neurodegenerative Disorders
Number of Conditions: 4
Huntington’s Disease
Specialty: Genetics
Category: Neurological and Neurodegenerative Disorders
Sub-category: Neurodegenerative Disorders
Symptoms:
involuntary jerking or writhing movements (chorea); muscle problems such as rigidity or muscle contracture; slow or abnormal eye movements; difficulty with speech or swallowing; cognitive impairments including difficulty organizing, prioritizing, or focusing tasks; behavioral changes such as irritability, depression, or apathy
Root Cause:
Caused by a mutation in the HTT gene, resulting in abnormal repetition of the CAG nucleotide sequence, leading to toxic accumulation of mutant huntingtin protein and progressive brain cell death.
How it's Diagnosed: videos
Clinical evaluation of symptoms, family history, genetic testing confirming the presence of expanded CAG repeats in the HTT gene. Imaging studies such as MRI or CT may show brain atrophy in advanced cases.
Treatment:
No cure exists, but symptomatic treatments include medications for chorea, psychiatric symptoms, and supportive care such as physical, occupational, and speech therapies.
Medications:
Medications include tetrabenazine and deutetrabenazine (vesicular monoamine transporter 2 inhibitors) for controlling chorea. Antidepressants like SSRIs or SNRIs and antipsychotics such as olanzapine or risperidone may be prescribed for psychiatric symptoms.
Prevalence:
How common the health condition is within a specific population.
Affects approximately 5-10 per 100,000 people worldwide, though prevalence varies by population.
Risk Factors:
Factors or behaviors that increase the likelihood of developing the condition.
Family history of Huntington’s disease is the primary risk factor due to its autosomal dominant inheritance pattern.
Prognosis:
The expected outcome or course of the condition over time.
Progressive and ultimately fatal. Life expectancy after onset is approximately 15-20 years.
Complications:
Additional problems or conditions that may arise as a result of the original condition.
Include severe disability, aspiration pneumonia, weight loss, depression, suicide, and heart failure.
Friedreich’s Ataxia
Specialty: Genetics
Category: Neurological and Neurodegenerative Disorders
Sub-category: Neurodegenerative Disorders
Symptoms:
difficulty walking (ataxia); loss of sensation in arms and legs; speech difficulties (dysarthria); muscle weakness; scoliosis; diabetes; vision and hearing impairments
Root Cause:
Caused by a mutation in the FXN gene, leading to decreased production of frataxin, a protein essential for mitochondrial function, causing oxidative stress and cell damage, particularly in neurons and muscles.
How it's Diagnosed: videos
Clinical examination, family history, genetic testing for FXN gene mutation, and imaging studies such as MRI for neurological changes. Electromyography and nerve conduction studies may also be used.
Treatment:
No cure exists; management focuses on symptomatic relief through physical therapy, orthopedic interventions for scoliosis, and management of diabetes if present.
Medications:
While no disease-specific drugs exist, antioxidants like idebenone and experimental treatments targeting mitochondrial dysfunction are being studied. Symptomatic treatments include baclofen or tizanidine for spasticity.
Prevalence:
How common the health condition is within a specific population.
Approximately 1 in 50,000 people are affected.
Risk Factors:
Factors or behaviors that increase the likelihood of developing the condition.
Inherited in an autosomal recessive manner; having two mutated copies of the FXN gene increases risk.
Prognosis:
The expected outcome or course of the condition over time.
Progressive condition with most individuals requiring a wheelchair within 10-20 years of onset. Life expectancy is often reduced due to cardiac complications.
Complications:
Additional problems or conditions that may arise as a result of the original condition.
Cardiomyopathy, diabetes, scoliosis, and severe loss of mobility.
Spinal Muscular Atrophy (SMN1 Gene Mutation)
Specialty: Genetics
Category: Neurological and Neurodegenerative Disorders
Sub-category: Neurodegenerative Disorders
Symptoms:
muscle weakness and atrophy; difficulty breathing and swallowing; delayed motor development; floppy baby syndrome in severe cases; reduced or absent tendon reflexes
Root Cause:
Caused by mutations or deletions in the SMN1 gene, leading to insufficient production of the survival motor neuron (SMN) protein, essential for motor neuron health.
How it's Diagnosed: videos
Genetic testing to detect SMN1 mutations, electromyography to assess nerve-muscle interaction, and clinical evaluation of symptoms.
Treatment:
Disease-modifying therapies such as nusinersen, risdiplam, and onasemnogene abeparvovec-xioi (gene therapy) aim to increase SMN protein production. Supportive care includes respiratory support, physical therapy, and nutritional support.
Medications:
Nusinersen (antisense oligonucleotide), risdiplam (oral SMN2 splicing modifier), and onasemnogene abeparvovec-xioi (gene therapy).
Prevalence:
How common the health condition is within a specific population.
Affects approximately 1 in 10,000 live births.
Risk Factors:
Factors or behaviors that increase the likelihood of developing the condition.
Autosomal recessive inheritance; both parents must carry a mutation in the SMN1 gene.
Prognosis:
The expected outcome or course of the condition over time.
Varies by type; early treatment can significantly improve outcomes. Without treatment, severe forms can be fatal in infancy or childhood.
Complications:
Additional problems or conditions that may arise as a result of the original condition.
Respiratory failure, scoliosis, joint contractures, and feeding difficulties.
Amyotrophic Lateral Sclerosis (ALS) with Genetic Causes
Specialty: Genetics
Category: Neurological and Neurodegenerative Disorders
Sub-category: Neurodegenerative Disorders
Symptoms:
progressive muscle weakness; spasticity; difficulty speaking (dysarthria); difficulty swallowing (dysphagia); breathing difficulties; muscle twitching (fasciculations)
Root Cause:
Genetic mutations, such as in SOD1, C9orf72, TARDBP, or FUS, cause dysfunction in motor neuron function, leading to degeneration and muscle atrophy.
How it's Diagnosed: videos
Diagnosis is based on clinical evaluation, electromyography, nerve conduction studies, and genetic testing to confirm familial cases. MRI may exclude other conditions.
Treatment:
Disease-modifying drugs like riluzole and edaravone may slow progression. Supportive care includes physical therapy, speech therapy, and respiratory support.
Medications:
Riluzole (glutamate inhibitor) and edaravone (antioxidant) are FDA-approved for ALS. Symptomatic treatments include antispasticity drugs like baclofen or tizanidine .
Prevalence:
How common the health condition is within a specific population.
Familial ALS accounts for approximately 5-10% of ALS cases, with overall ALS prevalence being about 2 per 100,000 people annually.
Risk Factors:
Factors or behaviors that increase the likelihood of developing the condition.
Family history of ALS, specific genetic mutations, and environmental factors may play a role.
Prognosis:
The expected outcome or course of the condition over time.
Typically progressive and fatal within 3-5 years of symptom onset, though some genetic forms have slower progression.
Complications:
Additional problems or conditions that may arise as a result of the original condition.
Respiratory failure, malnutrition, communication difficulties, and significant caregiver burden.