Table 5.

Provides a list of possible MSA mimics and when to consider them

MSA mimics	Consider if…
Parkinson’s disease	Significant and sustained response to L-dopa (>30% improvement in UPDRS-III), anosmia, delayed onset of autonomic symptoms
Dementia with Lewy bodies60	Fluctuating consciousness and cognitive change with hallucination (particularly visual), not secondary to L-dopa treatment
Progressive supranuclear palsy63	Vertical saccade slowing, supranuclear gaze palsy Frontalis overactivity and retropulsion Frontal cognitive change, non-fluent variant primary progressive aphasia
Corticobasal degeneration64	Asymmetrical limb dystonia, alien limb
Vascular Parkinsonism65	Onset >75 years, vascular risk factors, dementia
Normal pressure hydrocephalus	Cognitive impairment, lack of upper limb signs
Neurogenetic conditions
Spinocerebellar ataxia types 1,2,3,6,7,12,1766	May have a positive family history, but deterioration likely slow
CANVAS67	Chronic dry cough, positive head impulse test, peripheral neuropathy
C9ORF72 expansion68	Positive family history, lower motor neurone signs (eg, fasciculation, wasting)
Friedreich’s ataxia66	Peripheral neuropathy, pes cavus, loss of lower limb reflexes cardiomyopathy, type two diabetes mellitus
Fragile X tremor–ataxia syndrome66	X-linked inheritance, peripheral neuropathy, behavioural disorders with executive dysfunction

CANVAS, cerebellar ataxia, neuropathy, vestibular areflexia syndrome; MSA, multiple system atrophy; UPDRS-III, Unified Parkinson’s Disease Rating Scale part III.