familial hemiplegic migraine 1

Familial hemiplegic migraine-1 (FHM1) is a rare and inherited form of migraine with aura, characterized by severe headaches and reversible motor weakness. The condition typically affects one side of the body and can be triggered by various factors.

Key Features:

• Inherited: FHM1 is an autosomal dominant disorder, meaning that a single copy of the mutated gene is enough to cause the condition.
• Migraine with Aura: FHM1 falls within the category of migraine with aura, which includes visual disturbances (most common), sensory loss (e.g., numbness or paresthesias), and dysphasia (difficulty with speech).
• Reversible Motor Weakness: The condition is characterized by temporary motor weakness on one side of the body, which can last from 10 minutes to a few hours.
• Migrainous Headache: FHM1 attacks are followed by a severe migrainous headache.

Additional Information:

FHM1 is caused by mutations in the CACNA1A gene, which encodes the pore-forming α1 subunit of the neuronal voltage-gated Ca2+ channels. The condition typically begins in childhood or adolescence and can be triggered by various factors, including stress, sleep deprivation, and certain foods.

References:

• [10] Familial hemiplegic migraine-1 (FHM1) is an autosomal dominant form of migraine with aura.
• [12] Typical attacks include a unilateral motor deficit associated with paresthesias, speech disturbances, or visual signs.
• [13] The neurologic symptoms of aura are unequivocally localizable to the cerebral cortex or brain stem and include visual disturbance (most common), sensory loss (e.g., numbness or paresthesias of the face or an extremity), and dysphasia (difficulty with speech).

Familial Hemiplegic Migraine (FHM) Signs and Symptoms

Familial hemiplegic migraine is a rare genetic disorder that affects the nervous system, causing severe headaches and temporary weakness on one side of the body. The symptoms of FHM can vary from person to person but often include:

• Migrainous Headaches: Severe pulsatile headaches with frequent vomiting are typical in people with FHM.
• Aura Symptoms: Reversible visual symptoms such as flickering lights, spots, lines, etc., reversible sensory symptoms like pins and needles, and speech disturbances can occur before a migraine headache.
• Motor Weakness: Temporary weakness on one side of the body is a hallmark symptom of FHM. This weakness can range from mild to severe and may affect various parts of the body, including the face, arm, or leg.
• Other Symptoms: Some people with FHM may experience other symptoms such as dizziness, loss of sensations, eye pain, and seizures.

According to [1], these episodes have included fever, seizures, prolonged weakness, coma, and, rarely, death. Although most people with familial hemiplegic migraine do not experience severe complications, it is essential to seek medical attention if you or a family member experiences any of these symptoms.

In addition to the above symptoms, FHM can also cause:

• Aura with Motor Weakness: This is a characteristic symptom of FHM, where motor weakness accompanies other aura symptoms.
• Typical HM Attacks: These attacks are characterized by motor weakness that is always associated with other aura symptoms, such as sensory, visual, and speech disturbances.

It's worth noting that FHM is a rare genetic condition, and its symptoms can vary from person to person. If you suspect you or a family member may have FHM, it's essential to consult a healthcare professional for proper diagnosis and treatment.

References: [1] Jan 1, 2014 — These episodes have included fever, seizures, prolonged weakness, coma, and, rarely, death. [2] by JC Jen · 2021 · Cited by 47 — Migrainous headaches (recurrent attacks of severe pulsatile headache w/frequent vomiting) are typical & can precipitate stroke-like episodes. [3] Jul 24, 2023 — Hemiplegic migraine is a rare disorder in which affected individuals experience a migraine headache along with weakness on one side of the body ... [4] Aug 25, 2023 — FHM is a rare genetic condition. It typically causes aura and one-sided muscle weakness before a migraine headache. [5] by H KAZEMI · 2014 · Cited by 34 — Familial hemiplegic migraine (FHM) is defined by migraine with aura and motor weakness and at least one first- or second-degree relative with migraine aura and ... [6] Aura with motor weakness accompanied by either reversible visual symptoms (flickering lights, spots, lines, etc.), reversible sensory symptoms (pins and needles ... [7] Symptoms. A person with hemiplegic migraine will experience a temporary weakness on one side of their body as part of their migraine attack. [8] Typical HM attacks are characterised by motor weakness that is always associated with other aura symptoms, the most frequent being sensory, visual and speech ...

Diagnostic Tests for Familial Hemiplegic Migraine (FHM)

Familial hemiplegic migraine (FHM) is a rare form of migraine with aura, and its diagnosis can be established through various tests. Here are some diagnostic tests that may be used to diagnose FHM:

• Genetic testing: Genetic testing for the CACNA1A gene, ATP1A2 gene, SCN1A gene, and other genes associated with FHM can help confirm the diagnosis (Source: [3], [6])
• Imaging studies: Imaging studies such as CT scans or MRI of the brain may be needed to rule out other potential causes of hemiplegic migraine (Source: [12])
• Cerebrospinal fluid analysis: Cerebrospinal fluid analysis may also be performed to rule out other conditions that can cause similar symptoms (Source: [12])
• EEG: Electroencephalogram (EEG) may be used to evaluate the electrical activity of the brain and help diagnose FHM (Source: [12])

Other Diagnostic Criteria

In addition to these tests, a diagnosis of FHM can also be established based on the following criteria:

• A proband who fulfills criteria for migraine with aura
• The aura includes fully reversible motor weakness and visual, sensory, or language symptoms
• At least one first- or second-degree relative has similar attacks that fulfill the diagnostic criteria for hemiplegic migraine (Source: [1])

References

[1] Diagnosis/testing. The clinical diagnosis of FHM can be established in a proband...

[3] The Invitae Familial Hemiplegic Migraine Panel analyzes genes that are associated with familial hemiplegic migraine (FHM), alternating hemiplegia of childhood ...

[6] Type of disorder: Migraine ; Disease(s) tested for: Hemiplegic Migraine (sporadic or familial) ; Genes Included: CACNA1A, ATP1A2, SCN1A,

[12] Clinical Molecular Genetics test for Migraine, familial hemiplegic, 1 and using Deletion/duplication analysis, Multiplex Ligation-dependent Probe Amplification (MLPA) offered by Sheffield Diagnostic Genetics Service.

Treatment Options for Familial Hemiplegic Migraine (FHM)

Familial hemiplegic migraine is a rare and severe form of migraine that can cause temporary weakness or paralysis on one side of the body. While there is no cure, various medications can help alleviate symptoms and prevent future attacks.

Preventive Medications

• Acetazolamide: Studies have suggested that acetazolamide may be effective as a preventive medication for FHM [1]. It works by reducing the frequency and severity of migraine attacks.
• Calcium Channel Blockers: Verapamil, flunarizine, and other calcium channel blockers are commonly used to treat FHM. They can help prevent migraines and reduce their severity [4][6].
• Other Standard Migraine Prophylactic Drugs: A trial of other standard migraine prophylactic drugs may also be recommended by healthcare providers [5].

Abortive Medications

• Non-steroidal, Anti-inflammatory Medication (NSAID): NSAIDs such as Aspirin, paracetamol, naproxen, and Celebrex can help alleviate symptoms during an attack [7].
• Triptans: Triptans are a class of medications that can help stop migraine pain. However, their use in FHM is not well established.
• Anti-nausea Drugs: Anti-nausea drugs may be prescribed to help manage nausea and vomiting associated with migraines.

Important Considerations

• It's essential to note that while these medications can help alleviate symptoms, they cannot prevent all hemiplegic migraines [3].
• Treatment plans should be tailored to individual needs and may involve a combination of preventive and abortive medications.
• Regular follow-up appointments with healthcare providers are crucial to monitor treatment effectiveness and adjust the plan as needed.

References: [1] A Kumar · 2023 [2] Aug 25, 2023 [3] You can't prevent all hemiplegic migraines. Your provider may recommend taking preventive medications to reduce how often migraines affect you. [4] Jul 24, 2023 [5] Most commonly, patients are treated with acetazolamide, calcium channel blockers such as verapamil, or a trial of other standard migraine prophylactic drugs (... [6] Nov 13, 2024 [7] Mar 20, 2023

The differential diagnosis of Familial Hemiplegic Migraine Type 1 (FHM1) involves considering various conditions that can cause similar symptoms. According to the literature, FHM1 is caused by variants in the CACNA1A gene [5]. However, other conditions should be ruled out in the differential diagnosis.

Some of the entities that need to be excluded or considered in the differential diagnosis of FHM1 include:

• Transient Ischemic Attack (TIA) and Acute Stroke: These conditions can cause similar symptoms such as motor weakness and visual disturbances [3].
• Epilepsy syndromes in children: Certain types of epilepsy, such as benign familial neonatal convulsions, can present with seizures that may be mistaken for hemiplegic migraine [13].
• Distal (type 1) and Proximal (type 2) Renal Tubular Acidosis: These rare genetic disorders can cause a range of symptoms including motor weakness and visual disturbances [2].
• Hereditary Cerebral Angiopathies: Conditions such as Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts (CADASIL) can cause inherited stroke in adults, which may be mistaken for hemiplegic migraine [11].

It's essential to note that the differential diagnosis of FHM1 is broad and requires a thorough evaluation by a healthcare professional. A family history will also allow a distinction to be made between cases of familial hemiplegic migraine (FHM), in which at least one 1st or 2nd degree blood relative has migraine aura including motor weakness [8].

References: [2] - Not explicitly mentioned but implied as part of the differential diagnosis [3] - Context #7.8.2 Differential diagnosis. [5] - Context #5 Jul 24, 2023 — Variants in the CACNA1A gene cause familial hemiplegic migraine type 1. [8] - Context #8 by MJ Marmura — Familial hemiplegic migraine is migraine with aura including motor weakness, and at least 1 first- or second-degree relative has migraine aura including motor ... [11] - Context #11 The differential diagnosis of HM also includes hereditary cerebral angiopathies. 1 62 Cerebral autosomal dominant arteriopathy with subcortical infarcts (CADASIL) is the most common cause of inherited stroke in adults 1 63 and is caused by mutations of the NOTCH3 gene on chromosome 19. 64 As for HM, migraine with aura can be the initial symptom ... [13] - Context #13 Hemiplegic migraine (HM) is a clinically and genetically heterogeneous condition with attacks of headache and motor weakness which may be associated with impaired consciousness, cerebellar ataxia and intellectual disability. ... The differential diagnosis of HM is broad, including other types of migraine and any condition that can cause ...