Describe a case of familial trigeminal neuralgia inherited in an autosomal dominant pattern.

Trigeminal neuralgia is typically a chronic, paroxysmal facial pain condition. Episodes are usually described as severe electric-like pain affecting one side of the face, involving branches of the fifth cranial nerve, often evoked by a trigger. The majority of cases are thought to be caused by compression of the trigeminal nerve, most commonly by an adjacent blood vessel, although other etiologies have been demonstrated as well. 

A 76-year-old man presented to the neurology clinic to establish care for treatment of his chronic trigeminal neuralgia, which had been diagnosed more than 20 years prior. His symptoms were well-controlled on oxcarbazepine. MRI brain showed normal course and caliber of the trigeminal nerves. Interestingly, he reported a strong family history of trigeminal neuralgia. Affected family members include his mother, four of five of his mother's siblings (two maternal aunts and two of three maternal uncles), one of his first cousins (maternal aunt’s daughter), and the patient's own daughter. The patient and all the aforementioned family members were affected on the left side of the face. 

This case describes a family affected by trigeminal neuralgia in an apparent autosomal dominant pattern of inheritance. There are few case reports of familial trigeminal neuralgia, and this case has a particularly high number of family members affected. Physicians should be aware that trigeminal neuralgia can rarely be a familial disorder, and should consider family history when evaluating patients for trigeminal neuralgia.