amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis:

Amyotrophic lateral sclerosis, also known as Lou Gehrig's disease, is a currently fatal neurological disorder. It is characterized by the progressive degeneration of motor neurons in the spinal cord and brain, first identified byJean-Martin Charcot in 1869

Approximately five thousand cases are reported of ALS each year in the United States. It is estimated that at any given time, about three hundred thousand have the disease

Twice as many men compared to women seem to be effected by ALS, mostly developing the disease between the ages of forty and seventy, though some feel it's effects as young as twenty. Only one out of ten will live longer than ten years after diagnosis

When motor neurons cease functioning, the muscles become weak and atrophic, especially in the extremities and those muscles used in speech, swallowing and breathing

There are three currently known classifications of amyotrophic lateral sclerosis:

Sporadic-- the most common form in the America
Guamanian-- the form observed in high frequency in Guam and the Trust Territories
Familial-- a suggested genetic dominance, still under investigation and accounting for only a small number of cases

Other terms besides those mentioned above as the three classification of ALS include spinal muscular atrophy, progressive bulbar palsy and lateral sclerosis. Other variations of ALS, whose prognosis is better, are primary lateral sclerosis, juvenile muscular atrophy and benign facial amyotrophy

Initial symptoms of ALS are small and often overlooked. They may include twitching and cramping of muscles, impaired use of the hands, arms, legs and feet, thick speech and difficulty in articulation and projection, tripping, dropping objects, abnormal exremental fatigue and uncontrollable fits of laughter or crying. Advanced stage symptoms also include shortness and difficulty of breathing and difficulty swallowing. It is, however, important to point out that amyotrophic lateral sclerosis does not impair the afferent nervous system or association neurons. Oddly, however, eye muscles are never effected

Amyotrophic lateral sclerosis is, at best, difficult to diagnose. No single test can determine ALS as the cause of symptoms. Through clinical examination and observation, physicians can usually rule out diseases that mimic ALS. A diagnostic workup includes:

electrodiagnostic testing, often including electomyography (EMG) and nerve conduction velocity (NCV)
blood and urine testing, specifically looking for high resolution serum protein electrophoresis
thyroid and parathyroid hormone levels
urine collection for heavy metals
spinal tap (lumbar puncture)
x-rays, including magnetic resonance imaging
myelogram of cervical spinal tissues
muscles and/or nerve biopsies
plantar reflex test for Babinski response

In 1991, familial ALS (shows up more than once in a family line) was linked to chromosome twenty-one. Two years later, a defective SOD1 was identified on the chromosome. The structural defect in the superoxide dismutase (SOD) enzyme reduced the enzyme's ability to protect against free radical damage to motor neurons. Other proposed causes include accumulation of glutamate, excessive ingestion of magnesium, autoimmune abnormalities, impaired arganine tolerance, abnormal CSF monamines or a persistent viral infection

In an emergency room setting, it is important to note that atropine does not stop oral secretions due to ALS