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X-linked periventricular heterotopia


Other Names for this Disease

  • Bilateral periventricular nodular heterotopia
  • BPNH
  • Heterotopia familial nodular
  • Heterotopia periventricular X-linked dominant
  • NHBP
See Disclaimer regarding information on this site. Some links on this page may take you to organizations outside of the National Institutes of Health.

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Can you provide me with information about X-linked periventricular heterotopia? Where can I access articles and case studies related to this condition?

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What is X-linked periventricular heterotopia?

X-linked periventricular heterotopia, a neuronal migration disorder, is characterized by the presence of clumps or clusters of neurons near the brain's ventricles (fluid-filled cavities). Most affected individuals are females with one altered gene (heterozygotes). The condition is often lethal in males. Affected individuals experience seizures beginning in the middle teen years.[1] Intelligence is usually normal, although mild intellectual disability including difficulty with reading and spelling may occur.[2] Individuals appear to be at increased risk for stroke and other vascular/coagulation problems.[1] X-linked periventricular heterotopia is caused by mutations in the FLNA gene. It is inherited in an X-linked dominant fashion.[2]
Last updated: 12/15/2009

What are the symptoms of X-linked periventricular heterotopia?

X-linked periventricular heterotopia predominantly affects females.[1][2] The condition usually becomes evident when seizures first appear, often during the teenage years. The clumps or clusters (nodules) around the ventricles are then visualized when magnetic resonance imaging (MRI) studies are done. Affected individuals usually have normal intelligence, although some have mild intellectual disability. Difficulty with reading and spelling (dyslexia) has been reported in some girls with this condition.[2] 

Less commonly, individuals with X-linked periventricular heterotopia may have more severe brain malformations, small head size (microcephaly), developmental delays, recurrent infections, blood vessel abnormalities, or other problems. Periventricular heterotopia may also occur in association with other conditions such as Ehlers-Danlos syndrome, which results in extremely flexible joints, skin that stretches easily, and fragile blood vessels.[2]

In X-linked periventricular heterotopia, males experience much more severe symptoms of the disorder than females, and in most cases die before birth.[1][2]

Last updated: 12/15/2009

What causes X-linked periventricular heterotopia?

X-linked periventricular heterotopia is caused by mutations in the FLNA gene. This gene provides instructions for producing the protein filamin A, which helps build the network of protein filaments (cytoskeleton) that gives structure to cells and allows them to change shape and move. Certain mutations in the FLNA gene result in an impaired FLNA protein that cannot perform this function, disrupting the normal migration patterns of neurons during brain development.[2]

More information about the FLNA gene can be found by clicking here.
Last updated: 12/14/2009

How is X-linked periventricular heterotopia inherited?

X-linked periventricular heterotopia is inherited in an X-linked dominant pattern. A condition is considered X-linked if the mutated gene that causes the disorder is located on the X chromosome, one of the two sex chromosomes. The inheritance is dominant if one copy of the altered gene in each cell is sufficient to cause the condition. A striking characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons. In about 50 percent of cases of X-linked periventricular heterotopia, an affected person inherits the mutation from a mother who is also affected. Other cases may result from new mutations in the gene. These cases occur in people with no history of the disorder in their family.[2]
Last updated: 12/14/2009

How might X-linked periventricular heterotopia be treated?

The treatment of X-linked periventricular heterotopia is symptomatic and supportive. Seizures may be controlled through standard methods, with carbamazepine most often the drug of choice (as most seizures are focal). However, anti-epileptic drugs should be selected based on attributes such as side effects, tolerability, and efficacy. It is recommended that individuals with X-linked periventricular heterotopia undergo carotid and abdominal ultrasound surveillance studies for aortic and carotid dissection and echocardiograms to monitor valvular abnormalities.[1] 
Last updated: 12/14/2009

Where can I access articles and case studies related to X-linked periventricular heterotopia?

PubMed is a searchable database of medical literature and lists journal articles that discuss X-linked periventricular heterotopia. Click on the link to view a sample search on this topic.
Last updated: 12/15/2009

References
Other Names for this Disease
  • Bilateral periventricular nodular heterotopia
  • BPNH
  • Heterotopia familial nodular
  • Heterotopia periventricular X-linked dominant
  • NHBP
See Disclaimer regarding information on this site. Some links on this page may take you to organizations outside of the National Institutes of Health.