Beyond cervical lipomas: myoclonus, gait disorder and multisystem involvement leading to mitochondrial disease.

Madelung's disease (benign symmetric lipomatosis) is a rare syndrome in which there are multiple lipomas around the neck, upper limbs and trunk in the context of chronic alcoholism. We report on a female patient with lipomas and slightly progressive myoclonus, neuropathy, myopathy, ataxia and respiratory systemic involvement (labelled in the past as Madelung's disease). Multisystem involvement and family history of lipomas led to the development of mitochondrial genetic tests, which can assess two concurrent mitochondrial mutations: the m.8344A>G mutation in MT-TK gene, related MERRF (myoclonic epilepsy with ragged-red fibre) phenotype and m.14484T>C mutation in the MT-ND6 gene responsible for Leber hereditary optic neuropathy phenotype.