Corticobasal syndrome
Corticobasal syndrome (CBS) is a rare, progressive atypical Parkinsonism syndrome and is a tauopathy related to frontotemporal dementia.[1][2] CBS is typically caused by the deposit of tau proteins forming in different areas of the brain.[1][3]
Classification
CBS is the most common type of corticobasal degeneration (CBD) although the terms CBD and CBS have been used interchangeably in the past.[2] The other three phenotypes of CBD are:[1]
- frontal-behavioral dysexecutive-spatial syndrome (FBS)
- nonfluent/agrammatic variant of primary progressive aphasia (naPPA), and
- progressive supranuclear palsy syndrome (PSPS).[1][4]
Symptoms and signs
Symptoms of CBS include apraxia, alien limb phenomenon, frontal deficits, and extrapyramidal motor symptoms such as myoclonus or rigidity.[5] Movement deficits often begin on one side and progress to the other.[1]
Pathophysiology
CBD is the pathology underlying approximately 50% of CBS cases.[6]
Diagnosis
The Armstrong criteria were proposed in 2013; the accuracy of these is limited and further research is needed.[7] Symptoms may be symmetric or asymmetric, with one or more of the following:
- limb rigidity or akinesia
- limb dystonia
- limb myoclonus, plus one of:
- orobuccal or limb apraxia
- cortical sensory deficit
- alien limb phenomena (more than simple levitation)
The onset is insidious with gradual progression, lasting one year or more, with no exclusion criteria present. The diagnosis is more likely if onset is after age 50, there is no family history (2 or more relatives), and there is no genetic mutation affecting T (e.g., MAPT).[8]
Probably sporadic CBS is more likely if there are two of:
- limb rigidity or akinesia
- limb dystonia
- limb myoclonus
- plus two of:
- orobuccal or limb apraxia,
- cortical sensory deficit
- alien limb phenomena (more than simple levitation)[8]
The diagnosis is excluded if there is evidence of:
- Lewy body disease
- multiple system atrophy
- Alzheimer's disease
- amyotrophic lateral sclerosis
- semantic or logopenic variant primary progressive aphasia
- structural lesion suggestive of focal cause
- granulin mutation or reduced plasma progranulin levels
- TDP-43 or fused in sarcoma (FUS) mutations[8]
The diagnostic criteria for clinical use may result in a misdiagnosis of other tau-based diseases.[7]
The probable criteria are proposed for clinical research.[7]
Differential
Other degenerative pathologies that can cause corticobasal syndrome include:
- Alzheimer's disease
- Pick's disease with Pick bodies
- Lewy body dementias
- Neurofilament inclusion body disease
- Creutzfeldt-Jakob disease
- Frontotemporal degeneration due to progranulin gene mutation
- Motor neuron disease‐inclusion dementia.[9]
The symptoms of classic CBS differ from CBD in that CBD also includes cognitive deficits in the executive functions.[10]
Prognosis
The average survival time after disease onset is estimated at 6.5 years.[2]
References
- Parmera JB, Rodriguez RD, Neto AS, Nitrini R, Brucki SM (2016). "Corticobasal syndrome: A diagnostic conundrum". Dementia Neuropsychologia (Review). 10 (4): 267–75. doi:10.1590/s1980-5764-2016dn1004003. PMC 5619264. PMID 29213468.
- Constantinides VC, Paraskevas GP, Paraskevas PG, Stefanis L, Kapaki E (August 2019). "Corticobasal degeneration and corticobasal syndrome: A review". Clinical Parkinsonism & Related Disorders. 1: 66–71. doi:10.1016/j.prdoa.2019.08.005. ISSN 2590-1125. PMC 8288513. PMID 34316603.
- Di Stasio F, Suppa A, Marsili L, et al. (May 2019). "Corticobasal syndrome: neuroimaging and neurophysiological advances". Eur. J. Neurol. 26 (5): 701–e52. doi:10.1111/ene.13928. hdl:11573/1225619. PMID 30720235. S2CID 73426149.
- Armstrong MJ, Litvan I, Lang AE, et al. (January 2013). "Criteria for the diagnosis of corticobasal degeneration". Neurology (Multicenter study). 80 (5): 496–503. doi:10.1212/WNL.0b013e31827f0fd1. PMC 3590050. PMID 23359374.
- Finger EC (April 2016). "Frontotemporal Dementias". Continuum (Minneap Minn) (Review). 22 (2 Dementia): 464–89. doi:10.1212/CON.0000000000000300. PMC 5390934. PMID 27042904.
- Gomperts SN (April 2016). "Lewy Body Dementias: Dementia With Lewy Bodies and Parkinson Disease Dementia". Continuum (Minneap Minn) (Review). 22 (2 Dementia): 435–63. doi:10.1212/CON.0000000000000309. PMC 5390937. PMID 27042903.
- Shimohata T, Aiba I, Nishizawa M (2016). "[Diagnoses of corticobasal syndrome and corticobasal degeneration]". Rinsho Shinkeigaku (in Japanese). 56 (3): 149–57. doi:10.5692/clinicalneurol.cn-000841. PMID 26876110.
- Alexander SK, Rittman T, Xuereb JH, Bak TH, Hodges JR, Rowe JB (August 2014). "Validation of the new consensus criteria for the diagnosis of corticobasal degeneration". J. Neurol. Neurosurg. Psychiatry. 85 (8): 925–29. doi:10.1136/jnnp-2013-307035. PMC 4112495. PMID 24521567.
- Hassan A, Whitwell JL, Josephs KA (November 2011). "The corticobasal syndrome-Alzheimer's disease conundrum". Expert Rev Neurother (Review). 11 (11): 1569–78. doi:10.1586/ern.11.153. PMC 3232678. PMID 22014136.
- Fredericks CA, Lee SE (2016). "The cognitive neurology of corticobasal degeneration and progressive supranuclear palsy". In Miller, Bruce L.; Boeve, Bradley F. (eds.). The Behavioral Neurology of Dementia (Second ed.). Cambridge, United Kingdom: Cambridge University Press. pp. 203–6. ISBN 9781107077201. OCLC 934020279.
[CBD is] reminiscent of classic CBS but with executive function deficits