MAPT mutations cause rapid progressive frontal temporal dementia: A case report: Biomarkers (non‐neuroimaging) / Differential diagnosis. (7th December 2020)

• Record Type: Journal Article
• Authors: Mao, Chenhui; Li, Jie; Zhou, Liangrui; Huang, Xinying; Lei, Dan; Liu, Caiyan; Dong, Liling; Gao, Jing
• Is Part Of: Alzheimer's & dementia. Volume 16(2020)Supplement 5
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-12-07
• Subjects: Alzheimer's disease -- Periodicals; Alzheimer Disease -- Periodicals; Dementia -- Periodicals; Démence; Maladie d'Alzheimer; Périodique électronique (Descripteur de forme); Ressource Internet (Descripteur de forme); 616.83
• DOI: 10.1002/alz.041632
• Languages: English
• ISSNs: 1552-5260

Abstract

Abstract: Background: Frontal temporal dementia (FTD) was a heterogeneous disease entity which was divided into behavior variant FTD (bvFTD), semantic dementia and none fluent progressive aphasia. The pathologic and genetic mechanism was much more complicated and intercrossed. Mutations in the microtubule‐associated protein tau (MAPT) gene were the first to be associated with inherited FTD and the clinicopathological phenotypes depended on tau isoform composition, relative disposition of abnormal tau in neurons and glia, as well as different anatomic distribution of tau pathology and neuronal loss. Method: We reported a proven case of rapid progressive FTD with detail clinical description, neuroimaging, neuropathology and genetic data. Then we discussed the diagnosis and differential diagnosis thoughts. Result: It was a 31 years old female patient admitted with behavior and psychiatric symptoms as well as rapid progressive dementia for 10 months. The onset symptoms included abnormal behavior, changed personality and apathy. Then she had cognitive disorder, declined memory, however, the ability of housekeeping, taking care of herself and daily life was kept. About 4 months later, she got dysarthria. No family history was found. Encephalitis was suspected. Brain MRI showed unilateral atrophy of right frontal and temporal lobe with white matter lesions. Lumber puncture revealed no inflammation reactions. Systemic screening for antibodies, abnormal metabolites, tumors was negative. Brain biopsy of right frontal lobe revealed severe loss and degeneration of neurons with extensive proliferation of glial cells. No active inflammation or necrosis was seen. Neurodegeneration was suspected. Genetic sequencing suggested MAPT (NM_005910.5) exon8 c.796C>G p.leu266val, which was a definite pathogenic mutation. The final diagnosis was MAPT related FTD. Conclusion: We reported an atypical case of bvFTD caused by MAPT mutation which was difficult in the diagnosis process, because of the short and rapid course and atypical neuroimaging manifestation.