Sign Up for a Free Account
  • Updated 10.11.2023
  • Released 07.01.1993
  • Expires For CME 10.11.2026

Alternating hemiplegia of childhood



Alternating hemiplegia of childhood is a rare disorder caused by mutations in the ATP1A3 gene, a gene that encodes the alpha3 subunit of Na,K-ATPase, thought to be neuron-specific. It is manifested by episodes of unusual posturing, hemiplegia, and progressive developmental and behavioral disturbance and seizures. At its onset in early childhood, the differential diagnosis is broad and includes more common childhood disorders, such as epilepsy. Flunarizine may decrease the frequency of spells and possibly moderate the disorder, but is not available in the United States. Reports suggest that ketogenic diet therapy is helpful as well. Other phenotypes, including rapid-onset dystonia-parkinsonism (RDP) cerebellar ataxia, areflexia, pes cavus, optic atrophy, sensorineural deafness (CAPOS), and hemidystonia with polymicrogyria have been associated with mutations in the same gene.

Key points

• Alternating hemiplegia of childhood is a rare disorder that, at onset, may mimic other neurologic disorders in children and requires a thorough evaluation to exclude other causes.

• Both familial and sporadic cases are associated with causative mutations in the ATP1A3 gene.

• Flunarizine, available in Europe, and ketogenic diet therapy have been reported to be helpful in this disorder.

Historical note and terminology

Alternating hemiplegia is a rare disorder of childhood originally described by Verret and Steele as a form of hemiplegic migraine of infancy (43). Subsequent reports suggested that the syndrome was a variant of complicated or basilar migraine despite important differences in symptoms and course. Krageloh and Aicardi were the first to emphasize that alternating hemiplegia of childhood is a nosologic entity distinct from migraine (11). The International Classification of Headache Disorders (06) lists alternating hemiplegia of childhood as a syndrome that may be associated with migraine. However, the association is not clear, and familial hemiplegic migraine type 2 is associated with mutations in a gene (ATP1A2) that codes for a different subunit of the Na,K-ATPase protein. Others have subsequently underscored the uniqueness of alternating hemiplegia as a clinical entity (23; 22). Revision of the diagnostic criteria for alternating hemiplegia of childhood has been proposed (17).

This is an article preview.
Start a Free Account
to access the full version.

  • Nearly 3,000 illustrations, including video clips of neurologic disorders.

  • Every article is reviewed by our esteemed Editorial Board for accuracy and currency.

  • Full spectrum of neurology in 1,200 comprehensive articles.

  • Listen to MedLink on the go with Audio versions of each article.

Questions or Comment?

MedLink®, LLC

3525 Del Mar Heights Rd, Ste 304
San Diego, CA 92130-2122

Toll Free (U.S. + Canada): 800-452-2400

US Number: +1-619-640-4660



ISSN: 2831-9125