Behavioral variant frontotemporal dementia with pathogenic variant in MAPT presenting as dementia with Lewy body disease

Authors

• Tianxu Xia, Icahn School of Medicine at Mount Sinai
• Clara Li, Icahn School of Medicine at Mount Sinai
• Ayuko Iverson, Icahn School of Medicine at Mount Sinai
• Jessica Spat-Lemus, Montclair State UniversityFollow
• Amy Woroch, Icahn School of Medicine at Mount Sinai
• Georges Naasan, Icahn School of Medicine at Mount Sinai

Document Type

Preprint

Publication Date

2-2025

Journal / Book Title

Neurocase

Abstract

A 75-year-old right-handed Chinese American man presented to behavioral neurology clinic for a second opinion of dementia with Lewy body disease (DLB). The clinical history indicated a progressive multi-domain cognitive impairment starting in 2021 and including recurrent well-formed visual hallucinations, parkinsonism, dysautonomia, hypersomnia, apathy and paranoid delusions. The clinical manifestations met the criteria for a probable DLB diagnosis. In addition, family reported personality changes, disinhibition and compulsive behaviors, which suggested prefrontal cortex dysfunction. Brain MRI revealed disproportionate volume loss in the bilateral frontal lobes including the orbitofrontal cortices. Family history revealed that multiple firstand second-degree relatives had been diagnosed with early onset dementia or other central nervous system illnesses such as Parkinson’s disease. A heterozygous pathogenic variant in the microtubule-associated protein Tau (MAPT) was identified through genetic testing and confirmed the diagnosis of autosomal dominant MAPT-related frontotemporal dementia (FTD). This case is the first reported instance of MAPT-related FTD presenting with well-formed visual hallucinations in an elderly Chinese American. Concomitant neuropathologies cannot be ruled out, and there is no conclusive evidence that MAPT mutations alone manifest as psychosis. Genetic forms of FTD may present differently than sporadic cases and may mimic other dementia syndromes. Genetic FTD should be suspected in patients with extensive family history of early onset dementia even when the clinical syndrome seems consistent with other recognizable neurodegenerative disorders.

DOI

10.1080/13554794.2024.2440548

MSU Digital Commons Citation

Xia, Tianxu; Li, Clara; Iverson, Ayuko; Spat-Lemus, Jessica; Woroch, Amy; and Naasan, Georges, "Behavioral variant frontotemporal dementia with pathogenic variant in MAPT presenting as dementia with Lewy body disease" (2025). Department of Psychology Faculty Scholarship and Creative Works. 730.
https://digitalcommons.montclair.edu/psychology-facpubs/730

Published Citation

Published in final edited form as: Neurocase. 2025 February ; 31(1): 23–28. doi:10.1080/13554794.2024.2440548.