Migraine is the intense, throbbing pain usually in one side of the head accompanied by additional symptoms such as vomiting, nausea and sensitivity to sound and light. Familial hemiplegic migraine (FHM) is a type of migraine that runs in the families. Migraines normally continue through four stages which are known as prodrome, aura, headache and post-drome. The symptoms of prodrome are the warning signs before migraine occurs such as mood changes and neck stiffness. The aura can develop before or during the migraine that includes sensory, motor and verbal disturbances. During the migraine attack, the symptoms can include blurred vision, throbbing pain, nausea and sensitivity to light. The post-drome periods can present moodiness, condition and exhaustion. Some of the types of familial hemiplegic migraine include type 1, type 2 and type 3 which are linked to the specific genes that cause the different type of this condition.
Causes
The mutation in various genes such as CACNA1A, ATP1A2, SCN1A and PRRT2 genes has been identified to cause FHM. The first three genes produce proteins that are involved in the transportation of ions across cell membranes. The transportation of these ions is essential for the normal signaling between neurons. The genetic mutation of these three genes can affect the normal release and uptake of various neurotransmitters. The function of the PRRT2 gene is also believed to interact with a protein that assists with the control of this signaling process. Research indicates that the genetic mutation of this gene may disrupt the control of neurotransmitters release. This condition is inherited in an autosomal dominant pattern meaning a single defective gene in each cell can cause this condition. In most of the cases, a single parent of the affected individual presents this disorder.
Symptoms
Commonly, the individuals with the FHM exhibit symptoms similar to other types of migraines with aura, although this condition includes the motor aura in addition. The motor aura presents muscle weakness that occurs on a single side of the body initially developing in the hand or the foot which moves up the arm or the leg. The motor aura can last for several days or even weeks but is always reversible. The severity of this muscle weakness can range from mild clumsiness to complete paralysis on a single side of the body. The FHM symptoms can also present fever, confusion, increase in white blood cells in the cerebrospinal fluid and even loss of consciousness.
Diagnosis
The diagnosis is based on the symptoms of motor aura which typically occurs with FHM that does not represent the other types of migraine. In order to diagnose this condition, the affected individual must present two migraine attacks with the motor aura in addition to the typical aura symptoms. The affected individual must also have a first-degree relative such as parents or the second-degree relative like uncles who must also have this condition.
Treatment
The treatment is based on the severity of the condition and the symptoms evident. The treatments are usually focused on the management of the symptoms and to prevent migraines. In addition, some of the suggestions for this condition include resting in a dark place and to keep well hydrated. During the acute form of a migraine, pain relievers are recommended.
References
https://migraine.com/migraine-types/familial-hemiplegic-migraine/
https://ghr.nlm.nih.gov/condition/familial-hemiplegic-migraine#inheritance
https://rarediseases.info.nih.gov/diseases/2638/familial-hemiplegic-migraine-type-1
http://www.mgz-muenchen.com/disorders/diagnose/familial-hemiplegic-migraine-type-3-fhm3.html
