Frontotemporal Dementias: A Review

Abstract

Dementia is a clinical state characterized by loss of function in multiple cognitive domains. It is a costly disease in terms of both personal suffering and economic loss. Frontotemporal dementia (FTD) is the term now preferred over Picks disease to describe the spectrum of non-Alzheimers dementias characterized by focal atrophy of the frontal and anterior temporal regions of the brain. The prevalence of FTD is considerable, though specific figures vary among different studies. It occurs usually in an age range of 35–75 and it is more common in individuals with a positive family history of dementia. The risk factors associated with this disorder include head injury and family history of FTD. Although there is some controversy regarding the further syndromatic subdivision of the different types of FTD, the three major clinical presentations of FTD include: 1) a frontal or behavioral variant (FvFTD), 2) a temporal, aphasic variant, also called Semantic dementia (SD), and 3) a progressive aphasia (PA). These different variants differ in their clinical presentation, cognitive deficits, and affected brain regions. Patients with FTD should have a neuropsychiatric assessment, neuropsychological testing and neuroimaging studies to confirm and clarify the diagnosis. Treatment for this entity consists of behavioral and pharmacological approaches. Medications such as serotonin reuptake inhibitors, antipsychotics, mood stabilizer and other novel treatments have been used in FTD with different rates of success. Further research should be directed at understanding and developing new diagnostic and therapeutic modalities to improve the patients' prognosis and quality of life.

On the generation of shared symbols

“…Social deficits may be seen during conversational exchanges where a patient is unable to keep track of events occurring during the interaction, and thus is unable to hold a coherent conversation. Semantic dementia, also referred to as temporal variant FTD (tvFTD), is associated with predominantly temporal lobe atrophy, typically greater in the left than in the right hemisphere (Weder, Aziz, Wilkins, & Tampi, 2007). Studies involving semantic dementia patients show that the anterior temporal lobes are important for accessing knowledge of coherent concepts (Lambon Ralph, et al, 2010).…”

Papel da proteína Tau na fisiopatologia da demência frontotemporal

“…Contudo, a frequência de mutação do gene codificador da proteína Tau nos casos de DFT esporádica é baixa. Em pacientes com histórico familiar da doença, a mutação ocorre de 9,4% a 10,5% dos casos 4,10 . Em pacientes sem o histórico familiar da demência, ocorre uma mutação de íntrons e éxons no gene da proteína Tau 25 .…”

“…Segundo as manifestações clínicas, o diagnóstico de DFT é usualmente proposto para classificar, aproximadamente, 15% a 20% das síndromes demenciais. De acordo com critérios anatomopatológicos, estima-se que 3% a 10% dos casos diagnosticados postmortem correspondem às DFTs, sendo esse número mais elevado (20%) nos casos de demência degenerativa pré-senil 4 .…”

“…Na afasia progressiva não fluente o paciente apresenta atrofia assimétrica do hemisfério esquerdo. A apresentação clínica caracteriza-se por dificuldade na pronúncia e na fluência verbal e padrão de discurso anormal, muitas vezes evoluindo para mutismo 4 . Dificuldades de linguagem incluem agramatismo, parafasias de fonemas, anomia, repetição, apraxia de discurso e agrafia 7 .…”

A Case of Frontotemporal Dementia in the Shadow of Schizophrenia Diagnosis

“…Clinical presentation often includes deficiency in performing daily activities, decrease in self-care, decrease in human relations, and change in eating habits. Disorientation, distractibility, disinhibition, perseverations, compulsive and stereotypical behaviors, and lack of insight can be observed in the psychiatric examination (4,5).Imaging studies will depict medial and anterior temporal lobe degeneration (6). Different psychiatric symptoms can be seen in FTD cases related to the affected neuroanatomical regions.…”