Neurodegeneration with brain iron accumulation (NBIA)
Hallervorden-Spatz disease; Pantothenate kinase-associated neurodegeneration; PKAN; NBIA
Neurodegeneration with brain iron accumulation (NBIA) are a group of very rare nervous system disorders. They are passed down through families (inherited). NBIA involves movement problems, dementia, and other nervous system symptoms.
Causes
Symptoms of NBIA begin in childhood or adulthood.
There are 10 types of NBIA. Each type is caused by a different gene variant. The most common gene variant causes the disorder called PKAN (pantothenate kinase-associated neurodegeneration).
People with all forms of NBIA have a buildup of iron in an area deep inside the brain called the basal ganglia as well as other areas of the brain that help regulate movements.
Symptoms
NBIA mainly causes movement problems. Other symptoms may include:
- Dementia
- Difficulty speaking
- Difficulty swallowing
- Muscle problems such as rigidity or involuntary muscle contractions (dystonia)
- Seizures
- Tremor
- Vision loss, such as from retinitis pigmentosa
- Weakness
- Writhing movements
- Toe walking
Exams and Tests
Your health care provider will perform a physical exam and ask about symptoms and medical history.
Genetic tests can look for the variant gene that causes the disease. However, these tests aren't widely available.
Tests such as an MRI scan can help check for other movement disorders and diseases. The MRI usually shows iron deposits in the basal ganglia, and are called the "eye of the tiger" sign because of the way the deposits look in the scan. This sign suggests a diagnosis of PKAN.
Treatment
There is no specific treatment for NBIA. Treatment is mainly focused on regulating the symptoms. The most commonly used medicines to regulate symptoms include baclofen and trihexyphenidyl.
Outlook (Prognosis)
NBIA damages the nerves over time and symptoms get worse. It leads to a lack of movement, and often death by early adulthood.
Possible Complications
Medicine used to treat symptoms can cause complications. Being unable to move due to the disease can lead to:
- Blood clots
- Respiratory infections
- Skin breakdown
When to Contact a Medical Professional
Contact your provider if your child develops:
- Increased stiffness in the arms or legs
- Increasing problems at school
- Unusual movements
Prevention
Genetic counseling may be recommended for families affected by this illness. There is no known way to prevent it.
References
Jankovic J. Parkinson disease and other movement disorders. In: Jankovic J, Mazziotta JC, Pomeroy SL, Newman NJ, eds. Bradley and Daroff's Neurology in Clinical Practice. 8th ed. Philadelphia, PA: Elsevier; 2022:chap 96.
NBIA Disorders Association website. Overview of NBIA disorders. www.nbiadisorders.org/about-nbia/overview-of-nbia-disorders. Accessed August 20, 2024.
Review Date: 8/19/2024
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