Background: Alzheimer's disease (AD) is a clinically heterogeneous disease. Multiple atypical syndromes, distinct from the usual amnesic phenotype, have been described. In this context, the existence of a right variant of AD (RAD), characterized by enduring visuospatial impairment associated with right-sided asymmetric brain damage, has been proposed. However, to date, this phenotype remains controversial. In particular, its peculiar characteristics and the independence from more prevalent cases (especially the posterior cortical atrophy syndrome) have to be demonstrated. Objective: To explore the existence of focal RAD on the basis of existing literature. Methods: We performed a literature search for the description of atypical AD presentations, potentially evoking cases of focal RAD. To be considered as affected by RAD, the described cases had to present: 1) well documented right-sided asymmetry at neuroimaging; 2) predominant cognitive deficits localizable on the right hemisphere; 3) no specific diagnosis of a known variant of AD. Results: Twenty-one cases were found in the literature, but some of them were subsequently excluded because some features of a different clinical syndrome were overlapped with the clinical features of RAD. Thirteen positive cases, three of them with pathologically confirmed AD, remained. A common right clinical-radiological syndrome, characterized by memory and visuospatial impairment with temporal and parietal involvement, consistently emerged. However, the heterogeneity among the reports prevented a definitive and univocal description of the syndrome. Conclusion: Even if sporadic observations strongly support the existence of a focal RAD, no definitive conclusions can still be drawn about it as an independent condition.

Does the Right Focal Variant of Alzheimer's Disease Really Exist? A Literature Analysis / C. Abbate, P.D. Trimarchi, S. Inglese, S. Damanti, G.A.M. Dolci, S. Ciccone, P.D. Rossi, D. Mari, B. Arosio, R. Bagarolo, F. Giunco, M. Cesari. - In: JOURNAL OF ALZHEIMER'S DISEASE. - ISSN 1387-2877. - 71:2(2019 Jul 31), pp. 405-420. [10.3233/JAD-190338]

Does the Right Focal Variant of Alzheimer's Disease Really Exist? A Literature Analysis

C. Abbate
Primo
;
S. Damanti;D. Mari;B. Arosio;M. Cesari
2019-07-31

Abstract

Background: Alzheimer's disease (AD) is a clinically heterogeneous disease. Multiple atypical syndromes, distinct from the usual amnesic phenotype, have been described. In this context, the existence of a right variant of AD (RAD), characterized by enduring visuospatial impairment associated with right-sided asymmetric brain damage, has been proposed. However, to date, this phenotype remains controversial. In particular, its peculiar characteristics and the independence from more prevalent cases (especially the posterior cortical atrophy syndrome) have to be demonstrated. Objective: To explore the existence of focal RAD on the basis of existing literature. Methods: We performed a literature search for the description of atypical AD presentations, potentially evoking cases of focal RAD. To be considered as affected by RAD, the described cases had to present: 1) well documented right-sided asymmetry at neuroimaging; 2) predominant cognitive deficits localizable on the right hemisphere; 3) no specific diagnosis of a known variant of AD. Results: Twenty-one cases were found in the literature, but some of them were subsequently excluded because some features of a different clinical syndrome were overlapped with the clinical features of RAD. Thirteen positive cases, three of them with pathologically confirmed AD, remained. A common right clinical-radiological syndrome, characterized by memory and visuospatial impairment with temporal and parietal involvement, consistently emerged. However, the heterogeneity among the reports prevented a definitive and univocal description of the syndrome. Conclusion: Even if sporadic observations strongly support the existence of a focal RAD, no definitive conclusions can still be drawn about it as an independent condition.
Alzheimer’s disease; cognitive manifestations; left right asymmetry; right Alzheimer’s disease; right hemisphere; syndromic diversity; variant of Alzheimer’s disease; visuospatial
Settore MED/09 - Medicina Interna
Article (author)
File in questo prodotto:
File Dimensione Formato  
Does the Right Focal Variant of Alzheimer’s disease really exists. A literature analysis.pdf

accesso riservato

Tipologia: Pre-print (manoscritto inviato all'editore)
Dimensione 151.04 kB
Formato Adobe PDF
151.04 kB Adobe PDF   Visualizza/Apri   Richiedi una copia
Pubblicazioni consigliate

Caricamento pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/2434/671065
Citazioni
  • ???jsp.display-item.citation.pmc??? 2
  • Scopus 3
  • ???jsp.display-item.citation.isi??? 3
social impact