Biopsy-proven multiple sclerosis in an adult patient with atypical craniometaphyseal dysplasia.

Craniometaphyseal dysplasia (CMD) is a rare condition characterised by progressive, diffuse hyperostosis of cranial and long bones, with compression of cranial nerves, linked to mutations in or genes. Here we describe an adult case with clinical features of CMD, who developed cerebral expansive lesion of undetermined nature. Brain biopsy revealed active demyelinating lesions, consistent with multiple sclerosis. The genetic screening of target genes for CMD ( and ) resulted negative in this patient. The peculiar clinical association and the negativity of genetic analyses allow to hypothesise that other genetic causes, not already known, are responsible for the combination of these pathological conditions. Future studies aim to identify the genetic causes of CMD, which will be important to further understand the pathogenetic mechanism of this rare and invalidating disease.