[Familial hemiplegic migraine resulting in recurrent coma]

Area of Science:

• Neurology
• Genetics

Background:

• Familial hemiplegic migraine (FHM) is a rare subtype of migraine with aura, inherited in an autosomal dominant pattern.
• FHM is characterized by a wide spectrum of neurological symptoms, often complicating diagnosis.

Observation:

• A 71-year-old woman experienced recurrent headaches, hemihypoesthesia, fever, aphasia, reduced consciousness, and worsening ataxia.
• Cerebellar atrophy was noted on brain imaging, with mild cerebrospinal fluid pleocytosis.
• The patient had a family history of migraine and cerebellar ataxia.

Findings:

• Genetic testing identified a missense mutation in the CACNA1A gene, confirming the diagnosis of FHM.
• The CACNA1A gene is implicated in ion channel function, crucial for neuronal excitability.

Implications:

• FHM should be considered in the differential diagnosis for patients presenting with recurrent coma or encephalitis, particularly with cerebellar ataxia.
• Recognizing the genetic basis and diverse clinical presentation of FHM is vital for timely and accurate diagnosis.
• This case highlights the importance of genetic testing in diagnosing rare neurological disorders with overlapping symptoms.