Differences between the syndrome of PAF and multiple system atrophy
What are the major differences between the syndrome of PAF and multiple-system atrophy (MSA)?
MSA is characterized by autonomic dysfunction associated with either poor levodopa-responsive parkinsonism (MSA-P) or cerebellar ataxia (MSA-C), or both.
Orthostatic hypotension is one of the most disabling manifestations of MSA. Other autonomic symptoms include neurogenic bladder dysfunction, erectile dysfunction, nausea, abdominal pain, bloating, and anhidrosis.
Glial cytoplasmic inclusions that contain deposits of α-synuclein are found in oligodendroglia and some neurons of patients with MSA.
PAF, previously called idiopathic orthostatic hypotension, is a sporadic disorder characterized by orthostatic hypotension, usually accompanied by evidence of more widespread autonomic failure.
There are no other neurologic signs, and the natural history is slow progression over 10 to 15 years. PAF now is considered to be part of the spectrum of “Lewy body synucleinopathies,” where the intracytoplasmic eosinophilic inclusions are found in neurons of autonomic ganglia and postganglionic nerves.
After a few years, it is not uncommon that a patient presumed to have PAF develops symptoms and signs similar to MSA or less frequently Parkinson’s disease or dementia with Lewy bodies.
Accordingly, the diagnosis of PAF cannot be made with certainty until prolonged follow-up has been established.