Neurological Manifestations of Wilson's Disease: Pathophysiology and Localization of Each Component.

Wilson's disease (WD) is an autosomal recessive disease that presents mainly with hepatic, neurological, and psychiatric manifestations. Neurological manifestations have been described in the past. Nevertheless, the pathophysiology and the clinical relevance of these manifestations have not been described in great detail in the medical literature. We aim to consolidate the knowledge about the neurological manifestations of WD and present the pathophysiology of each neurological manifestation of the disease. We will give a brief definition, the provenance, and the pathophysiology of the neurological conditions. We collected data from the National Library of Medicine (PubMed) using regular keywords and medical subject headings. Studies were selected applying the following inclusion/exclusion criteria: (1) studies that used exclusively human subjects, (2) papers published in English, and (3) papers from 1990 onward. The exclusion criteria were (1) studies that used animals, (2) papers not published in English, and (3) papers published before 1990. Additional studies were included via reference lists of identified papers and related articles featured in PubMed and Google Scholar. Copper toxicity is the principal factor for brain degeneration seen in WD. Parkinsonism seen in WD has been associated with a nigrostriatal dopaminergic deficit. Resting tremor may have the same pathophysiology as parkinsonism. Action tremor is related to an accumulation of copper in the cerebellum's vermis and hemispheres. At the same time, essential tremor can be explained due to affection of the dentate nucleus. Choreoathetosis is produced due to increased activity of the direct pathway. We did not find specifically associated pathophysiology related to dysarthria. We assume that multiple parts of the brain are involved in that problem. Putamen nucleus damage is the leading cause that explains dystonia seen in WD along with the globus palidus. We did not find a specific localization for seizures in WD, but the pathology seems to be related to decreased levels of B6 and direct toxicity of copper on the brain.