Frontotemporal dementia

Clinic

• FTD or frontotemporal neurocognitive disorder encompasses several types of dementia involving the progressive degeneration of frontal and temporal lobes.
• FTDs broadly present as behavioral or language disorders with gradual onsets.
• The three main subtypes are a
  1. Behavioral variant frontotemporal dementia (bvFTD) previously known as Pick's disease
  2. Semantic dementia: Primary progressive aphasia – semantic variant (svPPA)
  3. Progressive nonfluent aphasia: Nonfluent variant (nfvPPA).
• Two rare distinct subtypes of FTD are
  1. Neuronal intermediate filament inclusion disease (NIFID), and
  2. Basophilic inclusion body disease.

Related disorders

• Corticobasal syndrome
• FTD-ALS also called FTD-MND

Neuronal intermediate filament inclusion disease[edit]

Neuronal intermediate filament inclusion disease (NIFID) is a rare distinct variant. The inclusion bodies that are present in NIFID are cytoplasmic and made up of type IV intermediate filaments. NIFID has an early age of onset between 23 and 56. Symptoms can include behavioural, and personality changes, memory and cognitive impairments, language difficulties, motor weakness, and extrapyramidal symptoms. NIFID is one of the FTLD-FUS proteopathies. Imaging commonly shows atrophy in the frontotemporal region, and in part of the striatum in the basal ganglia. Post-mortem studies show a marked reduction in the caudate nucleus of the striatum; frontal temporal gyri are narrowed with widened intervening sulci, and the lateral ventricles are enlarged.

Basophilic inclusion body disease[edit]

Another rare FTD variant, also a FTLD-FUS proteopathy, is basophilic inclusion body disease (BIBD).

Other characteristics[edit]

In later stages of FTD, the clinical phenotypes may overlap. People with FTD tend to struggle with binge eating and compulsive behaviors. Binge eating habits are often associated with changes in food preferences (cravings for more sweets, carbohydrates), eating inedible objects and snatching food from others. Recent findings from structural MRI research have indicated that eating changes in FTD are associated with atrophy (wasting) in the right ventral insula, striatum, and orbitofrontal cortex.

People with FTD show marked deficiencies in executive functioning and working memory. Most become unable to perform skills that require complex planning or sequencing. In addition to the characteristic cognitive dysfunction, a number of primitive reflexes known as frontal release signs are often able to be elicited. Usually the first of these frontal release signs to appear is the palmomental reflex which appears relatively early in the disease course whereas the palmar grasp reflex and rooting reflex appear late in the disease course.^{[citation needed]}

In rare cases, FTD can occur in people with amyotrophic lateral sclerosis (ALS) a motor neuron disease. The prognosis for people with ALS is worse when combined with FTD, shortening survival by about a year.