Parkinson’s disease

on 28.1.09 with 0 comments

  • May get Parkinsonism from drugs, toxins, a byproduct of heroine synthesis (MPTP), and influenza encephalitis

  • Movement d/o characterized by

    • Shuffling gate

    • Stooped over posture

    • Rigidity

    • Expressionless (“mask-like”) face

    • Tremor

  • Typical onset at 50 YOA

  • Pathogenesis

    • Degeneration of pigmented (dopaminergic) neurons in the substantia nigra of the midbrain

    • These neurons project to the striatum; the lack of dopaminergic input to the striatum causes the movement problems

  • Lewy bodies

    • Big, round eosinophilic intracytoplasmic inclusions in neurons of the substantia nigra

    • Not specific for Parkinson’s

    • Alpha-sinuclien is the major component

  • Dementia seen in about 10% of patients; some patients have dementia without movement problems – this is called diffuse Lewy body disease

  • Postencephalic Parkinsonism

    • Mostly seen after flu epidemic of 1914-1918

    • Starts months to years after initial encephalitis

    • Has been associated (rarely) with western equine, measles, and Japanese B viruses

    • Neuronal degeneration in the substantia nigra with the formation of tangles, not Lewy bodies

  • Striatonigral degeneration

    • C/S almost the same as Parkinson’s disease, but resistant to L-Dopa therapy

    • Loss of pigmented neurons of substantia nigra and loss of target cells in the striatum, but no Lewy bodies

Category: Pathology Notes



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