Amyotrophic Lateral Sclerosis (ALS)

Introduction

It has been over 150 years since the great French neurobiologist and clinician Jean-Martin Charcot first described the progressive, late onset motor neuron disease Amyotrophic lateral sclerosis (ALS). 

 With premature degeneration and death of upper and lower motor neurons provoking fatal paralysis as its noticeable clinical features. A myotrophic comes from the Greek language. “A” means no. “Myo” refers to muscle, and “Trophic” means nourishment – “No muscle nourishment.” When a muscle has no nourishment, it “atrophies” or wastes away. “Lateral” identifies the areas in a person’s spinal cord where portions of the nerve cells that signal and control the muscles are located. As this area degenerates, it leads to scarring or hardening (“sclerosis”) in the region.

Etiology

 The etiology of most ALS cases remains unknown, but 2% of instances are due to mutations in Cu/Zn superoxide dismutase (SOD1).There are two types of ALS sporadic and familial and they affect same neurons with similar pathology. Motor neurons reach from the brain to the spinal cord and from the spinal cord to the muscles throughout the body. The progressive degeneration of the motor neurons in ALS eventually leads to their demise. When the motor neurons die, the ability of the brain to initiate and control muscle movement is lost. With voluntary muscle action progressively affected, people may lose the ability to speak, eat, move and breathe. The motor nerves that are affected when you have ALS are the motor neurons that provide voluntary movements and muscle control.

Diagnosis

ALS is a difficult disease to diagnose. There is no one test or procedure to ultimately establish the diagnosis of ALS. It is through a clinical examination and series of diagnostic tests, often ruling out other diseases that mimic ALS, that a diagnosis can be established. A comprehensive diagnostic workup includes most, if not all, of the following procedures:

• Electrodiagnostic tests
  including electomyography (EMG) and nerve conduction velocity (NCV)
• Blood and urine studies
  including high resolution serum protein electrophoresis, thyroid and parathyroid
  hormone levels.
• Spinal tap
• X-rays, including magnetic
  resonance imaging (MRI)
• Myelogram of cervical spine
• Muscle and/or nerve biopsy
• A thorough neurological
  examination

Symptoms

The initial symptoms of ALS can be quite varied in different people. One person may have trouble grasping a pen or lifting a coffee cup, while another person may experience a change in vocal pitch when speaking. ALS is typically a disease that involves a gradual onset.

The rate at which ALS progresses can be quite variable from one person to another. Although the mean survival time with ALS is three to five years, many people live five, 10 or more years. Symptoms can begin in the muscles that control speech and swallowing or in the hands, arms, legs or feet. Not all people with ALS experience the same symptoms or the same sequences or patterns of progression. However, progressive muscle weakness and paralysis are universally experienced.

Signs and symptoms might include:

• Difficulty walking or
  doing normal daily activities
• Tripping and falling
• Weakness in your leg,
  feet or ankles
• Hand weakness or
  clumsiness
• Slurred speech or
  trouble swallowing
• Muscle cramps and
  twitching in your arms, shoulders and tongue
• Inappropriate crying,
  laughing or yawning
• Cognitive and behavioral
  changes

Treatment and Therapies

Recent years have brought a wealth of new scientific understanding regarding the physiology of this disease. There are currently four drugs approved by the U.S. FDA to treat ALS (Riluzole, Nuedexta, Radicava, and Tiglutik). These drugs can’t reverse damage of ALS but they reduce rate of progression, prevent complications, and make you comfortable and independent.

     Therapies include

• Breathing care: You’ll eventually have more difficulty breathing as your muscles weaken.
• Physical therapy: A physical therapist can address pain, walking, mobility, bracing and equipment needs that help you stay independent.
• Occupational therapy: An occupational therapist can help you find ways to remain independent despite hand and arm weakness.
• Speech therapy: A speech therapist can teach you adaptive techniques to make your speech more understandable.
• Nutritional support
• Psychological and social support

References

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