Pelizaeus-Merzbacher Disease with PLP1 Exon 1 Duplication, Previously Misdiagnosed as Cerebral Palsy: a Case Report.

Pelizaeus-Merzbacher disease (PMD) is a X-linked recessive disorder with dysmyelination in central nervous system caused by proteolipid protein 1 (PLP1) gene mutation. We report a case of PMD with PLP1 exon 1 duplication, previously misdiagnosed as cerebral palsy (CP). A 25-year-old male previously diagnosed as CP visited our clinic with progressive weakness and spasticity of bilateral lower limbs. Next generation sequencing revealed hemizygous duplication of exon 1 in PLP1. Additionally, multiplex ligation-dependent probe amplification assay of the patient's mother showed the same mutation, which could finally confirm the diagnosis as PMD. This patient received comprehensive rehabilitation program, and helped the patient to achieve functional improvement. Proper diagnosis and therapeutic plan will be needed for the patients with PMD, before diagnosing CP rashly.