The case we discussed below received a diagnosis of Multiple System Atrophy (see clinical details in post below) MSA is a neurodegenerative disease forming part of the Parkinson's-Plus syndromes. The incidence is sporadic mainly affecting individuals after 50 years of age with 9.3 mean survival years.
Pathology - multiple system atrophy affects three major neuronal systems with neuronal loss and gliosis; 1/ nigro-striatal degeneration ==> pure parkinsonism
(coronal section of brain illustrated above (from Wenning et al 2004)) shows shrinking of basal ganglia structures including putamen and globus pallidus.
2/ Autonomic failure ==>.Shy-Drager syndrome (erectile failure, impotence in men, urinary incontinence, fecal incontinence and postural hypotension)
3/Olivopontocerebellar atrophy = cerebellar features (gait and limb ataxia and incoordination). The initial presentation is usually dominated by one clinical syndrome. However, as the neurodegenerative process progresses, all three systems overlap leading to full blown MSA. UMN signs may also occur. Our patient had Parkinsonism with spasticity and query autonomic features. Autonomic and cerebellar features may occur expectedly as the condition progresses.
Features that are typical of MSA and were not demonstrated in this case are;
1/ Parkinsonism dominates the motor disorder in 80% of patients with MSA.
2/ 50% of patients with MSA have cerebellar signs which were absent or not manifested yet in this case (also 50% have spasticity which is a feature)
3/ Autonomic failure occurs in almost all patients - very severe and early in disease course.
• Men commonly present with impotence as 1st symptom, preceding motor symptoms by months or even years.
• Incontinence> retention common in both sexes (frequency and urgency due to detrusor hyperreflexia in 75%).
• Postual hypotension may occur.
Other features
1/Laryngeal dystonia (sustained muscular contraction) leading to stridor (30% of patients).
2/ Speech - quivering, strained and slurred component. Many develop aphonia.
3/ Dysphagia
4/ Postural instability EARLY in disease.
5/ Dementia is not a feature.
6/ Levodopa response = commonly absent or poor (good in 25%)
The diagnosis is usually clinical without recourse to investigations.
Adapted from;
Hughes, A.J., Ben-Shlomo,Y., Daniel, S.E. & Lees, A.J. 1992, "What features improve the accuracy of clinical diagnosis in Parkinson's disease: A clinicopathologic study", Neurology, vol. 42, no. 6, pp. 1142
Quinn, N. 1995,"Fortnightly Review: Parkinsonism--recognition and differential diagnosis", British medical journal, vol. 310, no. 6977, pp. 447-452
Further Reading; Wenning et al (2004)
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