PATHOGENESIS OF IDIOPATHIC PARKINSONISM

Idiopathic parkinsonism (Parkinson's disease) makes up the largest dia gnostic subgroup of patients with parkinsonism. Various hypotheses exi st regarding the pathogenesis of idiopathic parkinsonism: these includ e genetic predilection, aging, environmental factors, oxidative stress , excitotoxicity, autoimmunity, and trauma. We suggest that the pathog enesis of idiopathic parkinsonism is likely to be multifactorial, deri ving from environmental factor(s) acting upon a genetically predispose d individual. Because of the compelling evidence indicating common cli nical and pathological findings in idiopathic parkinsonism, Alzheimer' s disease, and amyotrophic lateral sclerosis, we believe that these co nditions result from pathological processes with more similarity than diversity. A primary glutamatergic cell neocortical abnormality provid es an attractive unifying explanation which may explain the overlappin g abnormalities found in idiopathic parkinsonism, Alzheimer's disease, and amyotrophic lateral sclerosis.