A chapter on spinocerebellar degenerations, written by Dr. Susan Perlman of UCLA, was recently published. It’s part of a “Handbook of Clinical Neurology.” Obviously this is written for neurologists so it is entirely medical terminology.
There is a small section on multiple system atrophy (MSA) in the chapter. MSA is described as “a sporadic ataxia which is felt to have a genetic substrate.”
A few things were interesting to me as I’d never heard them before:
* “Upper motor neuron signs were seen in 50% (spasticity; brisk tendon reflexes, pseudobulbar speech, and swallowing difficulties).”
* “Dementia, ophthalmoplegia, and chorea are not seen.” (I never heard that chorea is not seen in MSA before.)
* “Later in the course, stridor due to laryngeal abductor paralysis, progressive signs of obstructive sleep apnea, and neck muscle weakness heralded the terminal stages.” (I never heard that neck muscle weakness marks the end stages.)
* “Of the SCAs (15% of which can present with no family history), SCA3 is most likely to mimic MSA.”
Copied below is the abstract to the chapter.
Handbook of Clinical Neurology. 2011;100:113-40.
The spinocerebellar ataxias (SCA) are a large group of inherited disorders affecting the cerebellum and its afferent and efferent pathways. Their hallmark symptom is slowly progressive, symmetrical, midline, and appendicular ataxia. Some may also have associated hyperkinetic movements (chorea, dystonia, myoclonus, postural/action tremor, restless legs, rubral tremor, tics), which may aid in differential diagnosis and provide treatable targets to improve performance and quality of life in these progressive, incurable conditions. The typical dominant ataxias with associated hyperkinetic movements are SCA1-3, 6-8, 12, 14, 15, 17, 19-21, and 27. The common recessive ataxias with associated hyperkinetic movements are ataxia telangiectasia and Friedreich’s ataxia.
Fragile X tremor-ataxia syndrome (FXTAS) and multiple-system atrophy (a sporadic ataxia which is felt to have a genetic substrate) also have hyperkinetic features. A careful work-up should be done in all apparently sporadic cases, to rule out acquired causes of ataxia, some of which can cause hyperkinetic movements in addition to ataxia.
Some testing should be done even in individuals with a confirmed genetic cause, as the presence of a secondary factor (nutritional deficiency, thyroid dysfunction) can contribute to the phenotype.
Copyright © 2011 Elsevier B.V. All rights reserved.
PubMed ID#: 21496573 (see pubmed.gov for this abstract only)