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Achalasia
Below:
• What is achalasia?
• What causes achalasia?
• What are the symptoms?
• How is achalasia diagnosed?
• How is it treated?
• Are there any complications?
What
is achalasia?
Achalasia
is a motility disorder of the oesophagus (the tube that carries food from
the mouth to the stomach). In achalasia, the muscle of the lower oesophagus
and the lower oesophageal sphincter (the ring of muscle at the junction
of the oesophagus with the stomach) fail to relax and let food pass into
the stomach. This causes difficulty swallowing food.
Achalasia is quite rare and typically occurs in adults aged 25-60 years.
What causes achalasia?
Normally,
after swallowing, a wave of muscular contraction (peristaltic wave) passes
along the oesophagus. By the time the peristaltic wave reaches the lower
sphincter, the sphincter is open and the food passes into the stomach.
In achalasia, there is an absence of normal peristalsis in the lower oesophagus
and the lower oesophageal sphincter fails to relax. These abnormalities
cause food to stick in the oesophagus.
The
actual cause of achalasia is unknown. One theory is that achalasia is
an auto-immune disorder.
Early
in achalasia, microscopic inflammation can be seen in the muscle of the
lower oesophagus, especially around the nerves. As the disease progresses,
the nerves begin to degenerate and ultimately disappear, particularly
the nerves that cause the lower oesophageal sphincter to relax. Muscle
cells then begin to degenerate, possibly because of the damage to the
nerves. As a result the lower sphincter cannot relax and muscle in the
lower oesophageal body cannot support peristaltic waves. With time, the
body of the oesophagus stretches and becomes very dilated. |