MIGRAINE - Hemiplegic Migraine

Hemiplegic Migraine - The Basics

by Teri Robert, Lead Expert

To understand Hemiplegic Migraine, we have to understand that Migraine attacks are episodic manifestations of a genetic neurological disease. Migraine can present in a variety of ways. Hemiplegic Migraine is a rare form of Migraine, made more confusing by there being two variations: Familial Hemiplegic Migraine (FHM) and Sporadic Hemiplegic Migraine (SHM).

Diagnosing FHM and SHM can be difficult as the symptoms are also indicative of vascular disease. and can be thought to be stroke, epilepsy, or other conditions. A full neurological work up and careful review of medical history and symptoms are necessary to rule out other causes and confirm a diagnosis of FHM or SHM. Family medical history is especially helpful in diagnosing FHM.

FHM and SHM share the same symptoms, which will vary among different Migraineurs. The difference between the two is that FHM can be traced back in the family history and has been linked to mutations of specific genes on chromosomes 1 and 19. SHM is FHM without the familial connection and that particular genetic mutation.

Symptoms of FHM and SHM:

·         Episodes of prolonged aura (up to several days or weeks)

·         Hemiplegia (paralysis on one side of the body)

·         Fever

·         Meningismus (symptoms of meningitis without the actual illness and accompanying inflammation)

·         Impaired consciousness ranging from confusion to profound coma

·         Headache, which may begin before the hemiplegia or be absent

·         Ataxia (defective muscle coordination)

·         The onset of the hemiplegia may be sudden and simulate a stroke.¹

·         Nausea and/or vomiting

·         Phonophobia and/or photophobia

Treatment of FHM and SHM:
Treatment of Hemiplegic Migraine can be challenging. The symptoms are greater in number and more difficult to treat. Those who experience Hemiplegic Migraines absolutely need to educate themselves about their disease and treatment. It's very common to need to seek the care of an excellent Migraine specialist with an established track record for treatment as many other doctors have never treated a case of Hemiplegic Migraine.

·         Abortive and Pain Relief: Migraine-specific abortives, the triptans and ergotamines, are currently contraindicated in the treatment of Hemiplegic Migraine because of their vasoconstrictive properties and concerns about stroke. One small study was conducted, safely using triptans with patients with Hemiplegic Migraine, but more trials are needed before they're considered a safe option.² Since the triptans and ergotamines aren't options, other treatments such as NSAID's, antiemetics, and narcotic analgesics are generally used for relief of Hemiplegic Migraine.

·         Preventive: Given the severity of the symptoms and the contraindication of abortive medications, preventive regimens are considered especially important in the treatment of Hemiplegic Migraine. As noted above the genes for FHM are mapped on chromosomes 1 and 19, These code for the calcium channel. "The mutant calcium channel does not open and close properly and cannot regulate the amount of calcium coming into the cell, so calcium influx and efflux regulation goes awry. This in turn leads to neurons firing too easily."³ For this reason, calcium channel blockers are sometimes especially effective preventive medications for FHM.

A Word of Caution:
Migraineurs with Hemiplegic Migraine should give special consideration to wearing some kind of medical identification at all times since an attack can lead to impaired consciousness and an inability to speak. Medical identification can save valuable time in an emergency and assure that proper treatment is received far more quickly.

Diagnostic Criteria from the International Headache Society⁴:

Familial hemiplegic migraine (FHM)
Description: Migraine with aura including motor weakness and at least one first- or second-degree relative has migraine aura including motor weakness.
Diagnostic criteria:

1.    At least 2 attacks fulfilling criteria B and C

2.    Aura consisting of fully reversible motor weakness and at least one of the following:

1.    fully reversible visual symptoms including positive features (e.g., flickering lights, spots or lines) and/or negative features (i.e., loss of vision

2.    fully reversible sensory symptoms including positive features (i.e., pins and needles) and/or negative features (i.e., numbness)

3.    fully reversible dysphasic speech disturbance

3.    At least two of the following:

1.    at least one aura symptom develops gradually over ≥5 minutes and/or different aura symptoms occur in succession over ≥5 minutes

2.    each aura symptom lasts ≥5 minutes and <24 hours

3.    headache fulfilling criteria B–D for Migraine without aura begins during the aura or follows onset of aura within 60 minutes

4.    D. At least one first- or second-degree relative has had attacks fulfilling these criteria A–E

Comments:
It may be difficult to distinguish weakness from sensory loss. New genetic data have allowed a more precise definition of FHM than previously. Specific genetic subtypes of 1.2.4 Familial hemiplegic migraine have been identified: in FHM1 there are mutations in the CACNA1A gene on chromosome 19, and in FHM2 mutations occur in the ATP1A2 gene on chromosome 1.

Sporadic hemiplegic migraine
Description: Migraine with aura including motor weakness but no first- or second-degree relative has aura including motor weakness.
Diagnostic criteria:

1.    At least 2 attacks fulfilling criteria B and C

2.    Aura consisting of fully reversible motor weakness and at least one of the following:

1.    1. fully reversible visual symptoms including positive features (e.g., flickering lights, spots or lines) and/or negative features (i.e., loss of vision)

2.    2. fully reversible sensory symptoms including positive features (i.e., pins and needles) and/or negative features (ie, numbness)

3.    3. fully reversible dysphasic speech disturbance

3.    At least two of the following:

1.    1. at least one aura symptom develops gradually over ≥5 minutes and/or different aura symptoms occur in succession over ≥5 minutes

2.    2. each aura symptom lasts ≥5 minutes and <24 hours

3.    3. headache fulfilling criteria B–D for Migraine without aura begins during the aura or follows onset of aura within 60 minutes

4.    No first- or second-degree relative has attacks fulfilling these criteria A–E

Comments:
Epidemiological studies have shown that sporadic cases occur with approximately the same prevalence as familial cases. The attacks have the same clinical characteristics as those in Familial hemiplegic migraine. Sporadic cases always require neuroimaging and other tests to rule out other cause. A lumbar puncture is also necessary to rule out pseudomigraine with temporary neurological symptoms and lymphocytic pleocytosis. This condition is more prevalent in males and often associated with transient hemiparesis and aphasia.

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Migraine without aura
Description:
Recurrent headache disorder manifesting in attacks lasting 4–72 hours. Typical characteristics of the headache are unilateral location, pulsating quality, moderate or severe intensity, aggravation by routine physical activity and association with nausea and/or photophobia and phonophobia.
Diagnostic criteria:

1.    At least 5 attacks1 fulfilling criteria B–D

2.    Headache attacks lasting 4–72 hours (untreated or unsuccessfully treated)

3.    Headache has at least two of the following characteristics:

1.    unilateral location

2.    pulsating quality

3.    moderate or severe pain intensity

4.    aggravation by or causing avoidance of routine physical activity (e.g., walking or climbing stairs)

4.    During headache at least one of the following:

1.    nausea and/or vomiting

2.    photophobia and phonophobia