Atypical Familial Presentation of Chiari 1 Malformation: A Case Report.

Chari malformations are a group of developmental malformations involving the cerebellum, classified into four subtypes. Type 1 CM (CM1) can cause a heterogenous set of symptoms, ranging from neck pain, occipital headache, and nystagmus to cranial nerve palsies, limb numbness, and cerebellar dysfunction. Diagnosis can be particularly challenging in part due to the lack of understanding surrounding its pathogenesis, though it has been suggested that there may be some genetic component contributing. This report describes a case of familial CM1 in which a mother and her two daughters all demonstrated symptomatic and radiographic evidence of CM1. Notably, the two children presented with symptoms requiring surgical decompression prior to the age of three, which is uncommon. The mother only presented with symptoms after giving birth to her two children. Though the children both had initial symptoms, including difficulty swallowing as well as an established growth hormone deficiency, the mother did not present with such symptoms and did not have any known hypothalamic dysfunction. The pathogenesis of CM1 remains unknown, though it has been suggested that there is some genetic component involved. This report of familial CM1 adds to the body of literature. Familial MRI head screening and whole exome sequencing in individuals with family members showing signs of CM1 could help reveal a genetic pathogenesis for CM1.