Hallervorden-Spatz disease (PKAN)
Related Subjects:
| Dementias
ℹ️ About
- 🧬 Pantothenate kinase-associated neurodegeneration (PKAN), previously known as Hallervorden-Spatz disease, is a rare autosomal recessive neurodegenerative disorder.
- Characterised by progressive extrapyramidal symptoms, intellectual decline, and iron accumulation in the brain.
🧬 Aetiology
- 🧪 Caused by mutations in the PANK2 gene, which encodes pantothenate kinase 2, an enzyme essential for coenzyme A biosynthesis.
- ⚙️ Mutation leads to abnormal lipid metabolism, oxidative stress, and unexplained iron deposition in the basal ganglia.
- 🔬 Affects the globus pallidus, substantia nigra, and red nucleus → leading to pigmentary degeneration.
🩺 Clinical Features
- 🌀 Extrapyramidal signs: Rigidity, dystonia, choreoathetosis, tremor.
- ⚡ Pyramidal signs: Spasticity, hyperreflexia, corticospinal tract involvement.
- 🧠 Progressive dementia and intellectual decline.
- 👧 Typically adolescent onset (but can vary: childhood to adult-onset).
- ⏳ Life expectancy limited: death often occurs in the 2nd–3rd decade due to progressive neurological decline.
Differential Diagnosis
- Wilson’s disease (copper deposition, Kayser-Fleischer rings).
- Huntington’s disease (chorea, cognitive decline).
- Juvenile Parkinsonism.
- Other Neurodegeneration with Brain Iron Accumulation (NBIA) disorders (e.g. PLA2G6-associated neurodegeneration).
🔎 Investigations
- 🧲 MRI Brain: Classic “eye-of-the-tiger” sign in the globus pallidus (central hyperintensity with surrounding hypointensity on T2-weighted imaging due to iron deposition).
- 🧪 Genetic testing for PANK2 mutations confirms diagnosis.
💊 Management
- 🤝 Primarily supportive and symptomatic.
- 💊 Anticholinergics, baclofen, or botulinum toxin may help dystonia and spasticity.
- 🧠 Levodopa occasionally trialled, but benefit limited.
- 🩺 Deep brain stimulation (DBS) of globus pallidus may improve severe dystonia in selected cases.
- 🧑⚕️ Multidisciplinary care: neurology, physiotherapy, occupational therapy, and speech therapy.
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