Stanislav Šutovský1, Andrej Blaho1, Peter Weissman2, Hisham El Falougy2, Peter Turčáni1
Alzheimer’s disease (AD) and Frontotemporal lobar degeneration (FTLD) represent two neurodegenerative disorders with different histopathologic and clinical characteristics. In practice, nevertheless, we can encounter incorrect diagnosis or exchange of these two diseases. Diagnostic errors are mainly present in the incipient stages and/or in cases with atypical disease presentation. Common denominator of both entities is a gradual development of specific impairments of individual cognitive domains. In case of typical Alzheimer’s disease it is a decline of episodic memory, followed by time and space disorientation. Alternation of social behavior and amnesic aphasia occur only in advanced phases of disease. Atypical Alzheimer’s disease designates forms of the disease in which memory disturbances, time and space disorientation is not the main clinical symptom. Leading clinical manifestation is parietal syndrome and various combinations of the expressive and sensoric aphasia, dyslexia, dysgrafia, dyscalculia and visual agnosia. Frontotemporal lobar degeneration is demonstrated in three clinical sub-units: 1. Behavioral-dysexecutive variant FTLD (frontotemporal dementia), 2. Progressive non-fluent aphasia, 3. Semantic dementia. The most predisposed for the diagnostic confusion are atypical forms of Alzheimer’s disease, which can mimic syndromes of FTLD. In this article we analyze key diagnostic features of typical and atypical Alzheimer’s disease and syndromes of FTLD. We also try to specify characteristic symptoms of the individual entities based on caregiver references and results of clinical assessment.