Extremely Early-Onset Frontotemporal Dementia: A Case Report and Literature Review

Abstract

Background: In most cases, the onset of frontotemporal dementia (FTD) occurs between the ages of 45 and 65 years. However, some patients experience an extremely early disease onset. Objective: To investigate the clinical, genetic, and pathological features of extremely early-onset FTD. Methods: We conducted a comprehensive clinical, genetic, and neuropathological analysis of a 25-year-old patient experiencing the onset of behavioral variant frontotemporal dementia (bvFTD). In addition, we conducted a literature review and summarized the clinical, genetic, and pathological features of patients with FTD with onset age≤25 years. Results: The patient was diagnosed with bvFTD; however, there was no family history of FTD, no positive genetic test results and no deposition of TDP43, tau, ubiquitin, and synuclein in the brain. Literature screening identified 18 patients with onset age≤25 years with FTD. The youngest patient was 14-years-of-age. Most patients (8/14) had a positive family history. The most common clinical phenotype was the behavioral variant (12/14). Genetic results were reported for 11 patients; the most common pathogenic gene was MAPT (10/12), with four cases of G389 R, two cases of P301 S, one case of G335 S, one case of G335A, one case of G335 V, and one case of L315 R. Pathological results were reported for 13 patients; the most common pathological subtype was tau (8/13). Conclusion: FTD can start at an extremely early age. The most common phenotype of extremely early onset FTD was the behavioral variant, the most common pathogenic gene was MAPT, and the most common neuropathological type was tau.

A novel granulin mutation in logopenic variant primary progressive aphasias: Case report and literature review

“…GRN mutations are common in western countries, accounting for 34.6% of mutations in patients with FTD 17 , but GRN mutations are rare in China 18 , with a prevalence of just 1.2-2.6% 19 . Microtubuleassociated protein tau(MAPT) and coiled-coil-helix-coiled-coil-helix-domain(CHCHD10) gene may be the major genes affecting Chinese patients with FTLD 20 .…”

Mitochondrial Permeability Transition, Cell Death and Neurodegeneration

“…Frontotemporal dementia (FTD) has a number of phenotypic manifestations (the most common are behavioral (bvFTD) and language variants (lvFTD)) [110,111] and is characterized by the selective degeneration of the frontal and/or temporal lobe [112]. FTD is the second cause of degenerative dementia after Alzheimer's disease (AD), distinguished by an earlier onset with diagnosis between the ages of 45-65 years [113]. With a prevalence of 15-22 cases per 100,000 people [114], familial forms account for 30-50% of patients with FTD [112].…”