Parkinsonism in neurometabolic diseases

Neurometabolic disease are a wide and variegate group of genetic disorders, mostly recessively inherited, causing an alteration of specific biochemical pathways within cells. In most cases, they are characterized by a multi-organ involvement, but some diseases specifically affect the brain resulting in progressive neurodegenerative conditions. Though rare or ultra-rare, these disorders must be considered in the differential of adult-onset parkinsonism in the presence of atypical additional elements, such as hepatic dysfunction, bone alterations, hematological abnormalities, rapid motor deterioration or disease-specific clinical signs. Among these rare diseases, some are treatable, including some metal-accumulation disorders and some lysosomal storage diseases. Current available therapies, including chelating agents for metals and Enzyme Replacement Therapies can dramatically improve the natural history of some neurometabolic diseases, either by slowing disease progression or by reverting clinical signs and symptoms. Hence, it essential to recognize the most frequent neurometabolic disorders to achieve a timely diagnosis and start appropriate therapeutical interventions.