Under the Umbrella -- FTD with Motor Neuron Disease (FT...

Under the Umbrella -- FTD with Motor Neuron Disease (FTD/MND)

Overview

Frontotemporal Dementia with Motor Neuron Disease (FTD/MND) is also known as ALS (amyotrophic lateral sclerosis or Lou Gehrig's disease) with Dementia. Patients with this diagnosis may present with the same behavioral and/or language changes seen in other subtypes of FTD; in this subtype, however, these dementia changes are accompanied by weakness, muscle atrophy, and myoclonus (muscle jerks)—the cardinal features of ALS. It is important to note that patients with FTD/MND may first present with features of either FTD or ALS: the additional symptoms will develop as the disease progresses. As with the other FTDs, not every symptom will be experienced by every person, nor will these symptoms develop in a pre-ordained sequence. All patients with FTD/MND will experience a gradual, steady decline in functioning.


Key Clinical Features

The symptoms arising from motor neuron disease in these patients are those seen in ALS.

* Akinesia (increasing difficulty making voluntary movements)
* Muscle weakness and atrophy
* Fasciculations (muscle cramps and twitches)
* Dysphagia (difficulty swallowing)
* Dysarthria (problem speaking or forming words)
* Spasticity (tight and stiff muscles)
* Hyperreflexia (exaggerated reflexes)—especially notable is an overactive gag reflex. The Babinski reflex of the big toe is also characteristic in these patients.

The clinical spectrum of FTD/MND may include symptoms seen in other FTD subtypes. These include:

* Behavioral symptoms
* Emotional symptoms
* Cognitive symptoms
* Language symptoms

Neuroimaging Studies in FTD/MND patients often reveal decreased blood flow on both sides of the frontal and temporal lobes of the brain.


Key Pathologic Features

Upon autopsy, atrophy of the frontal and temporal lobes of the brain can be seen. When viewed under the microscope, brain cells in these affected areas are seen to have suffered neuronal loss, gliosis (overgrowth, or development of tumors), inclusions (Pick bodies) and spongiosis (swelling with excess fluid).

In FTD/MND patients pathologists also see degeneration of motor neurons in the brain stem. These disease changes are known to be responsible for the motor neuron disease, and are the same pathological finding seen in ALS patients.


Causes

Scientists have recently determined that the inclusions seen in the brain cells of FTD/MND patients contain deposits of the protein ubiquitin (they do not contain abnormal deposits of the protein tau, which is seen in other subtypes of FTD). The cause of these abnormal ubiquitin deposits is not known.


Genetics

The majority of FTD/MND is not hereditary.


Treatment

There is no cure for FTD/MND. Riluzole, the first drug approved for use in the treatment of ALS, may help slow the progression of ALS symptoms, especially difficulty swallowing. Other medications may help relieve the symptoms of muscle cramping and spasticity.


Management and Prognosis

Patients with this diagnosis usually experience a rapid decline in both physical and cognitive abilities. The course of FTD/MND may be as quick as 2-3 years, as opposed to the 5-10 year course more commonly seen among other FTD patients.

Physical therapy, including stretching exercises and low-impact exercise can help relieve muscle symptoms. Devices such as ramps, braces, walkers, and wheelchairs can help patients conserve energy and remain mobile. Speech therapy can help a patient develop strategies to speak more clearly. Over time alternate means of communication, such as speech synthesizers, may be of use.

The ALS features of the disorder eventually render patients unable to stand, walk, get in or out of bed on their own, or use their hands and arms. Difficulty swallowing and chewing impair the patient's ability to eat normally and increase the risk of choking. Patients eventually lose the ability to breathe on their own, and will require support on a ventilator for survival.


For additional information and support:
ALS Association (ALSA)
27001 Agoura Road
Suite 150
Calabasas Hills, CA 91301-5104
info@alsa-national.org
http://www.alsa.org


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Material prepared by Jennifer M. Farmer, MS, CGC, Website Clinical Consultant and Susan L-J Dickinson, MS, CGC, Website Medical and Science Writer.