Amyotrophic lateral sclerosis (ALS), sometimes called Lou Gehrig's disease, is a rapidly progressive, invariably fatal neurological disease that attacks the nerve cells (neurons) responsible for controlling voluntary muscles. In ALS, both the upper motor neurons and the lower motor neurons degenerate or die, ceasing to send messages to muscles. Unable to function, the muscles gradually weaken, waste away, and twitch. Eventually the ability of the brain to start and control voluntary movement is lost. Individuals with ALS lose their strength and the ability to move their arms, legs, and body. When muscles in the diaphragm and chest wall fail, individuals lose the ability to breathe without ventilatory support. The disease does not affect a person's ability to see, smell, taste, hear, or recognize touch, and it does not usually impair a person's thinking or other cognitive abilities. However, several recent studies suggest that a small percentage of patients may experience problems with memory or decision-making, and there is growing evidence that some may even develop a form of dementia. The cause of ALS is not known, and scientists do not yet know why ALS strikes some people and not others.
DIAGNOSTIC TESTING AND CODING
There is no one test or procedure to establish the diagnosis of ALS. The diagnosis of ALS is based on history, neurological findings consistent with the diagnosis of ALS and eletrophysiological and neuroimaging testing to rule out other impairments that may cause similar signs and symptoms. The diagnosis may be supported by electrophysiological studies (electromyogram [EMG] and nerve conduction study [NCS] but these tests may be negative or only suggestive of the diagnosis.
No cure has yet been found for ALS. However, the FDA has approved the first drug treatment for the disease-riluzole (Rilutek). Clinical trials with ALS patients showed that riluzole prolongs survival by several months. Riluzole does not reverse the damage already done to motor neurons, and patients taking the drug must be monitored for liver damage and other possible side effects. However, this first disease-specific therapy offers hope that the progression of ALS may one day be slowed by new medications or combinations of drugs. Other treatments for ALS are designed to relieve symptoms and improve the quality of life for patients. Multidisciplinary teams of health care professionals can design an individualized plan of medical and physical therapy and provide special equipment aimed at keeping patients as mobile and comfortable as possible. Physicians can prescribe medications to help reduce fatigue, ease muscle cramps, control spasticity, and reduce excess saliva and phlegm. Drugs also are available to help patients with pain, depression, sleep disturbances, and constipation.