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- What is achalasia?
Achalasia is a rare disease of the muscle of the esophagus (swallowing tube). The
term achalasia means "failure to relax" and refers to the inability of the lower
esophageal sphincter (a ring of muscle situated between the lower esophag us and
the stomach) to open and let food pass into the stomach. As a result, patients with
achalasia have difficulty in swallowing food.
- ACHALASIA CAUSE
The specific cause of achalasia is unknown. However, patients with achalasia have
two problems in the esophagus (the tube that carries food from the mouth to the
stomach).
* The lower two-thirds of the esophagus does not propel food toward the stomach
properly.
* The lower esophageal sphincter (LES), a circular band of muscle that lies at the
junction of the esophagus and the stomach, does not function correctly. Normally,
the LES helps prevent food from flowing backwards, from the stomach into the
esophagus. The LES should relax in response to swallowing to allow food to enter
the stomach.
In people with achalasia, the LES fails to relax, creating a barrier that prevents
food and liquids from passing into the stomach . One theory is that the ne rve cells
responsible for relaxation are destroyed by an unknown cause.
Damage to the LES and esophagus causes large volumes of food and saliva to
accumulate in the esophagus. Most people can initially compensate for this.
Eventually, the barrier progresses to the point where food and saliva cannot
reliably enter the stomach. As a result, food and saliva build up in the esophagus.
ACHALASIA SYMPTOMS
- The most common symptom of achalasia is difficulty swallowing (liquids or
solids). This problem begins slowly and progress gradually; many people do not
seek help until symptoms are advanced. Some people compensate by eating more
slowly and using specific maneuvers, such as lifting the neck or throwing the
shoulders back, to improve emptying of the esophagus.
Other symptoms can include chest pain, regurgitation of swallowed food and
liquid, heartburn, difficulty burping, a sensation of fullness or a lump in the throat,
hiccups, and weight loss.
ACHALASIA DIAGNOSIS
Achalasia is usually suspected based upon symptoms, although tests are needed to
confirm the diagnosis.
Chest x-rays — A simple chest x-ray may reveal abnormal changes in the
esophagus and absence of air in the stomach, two abnormalities that suggest
achalasia.
Barium swallow test — The barium swallow test is the primary screening test for
achalasia. The test involves swallowing a chalky-tasting, thick mixture of barium
while x-rays are taken. The barium shows the outline of the esophagus and LES
(figure 2).
- Barium swallows are usually performed under fluoroscopy, a continuous low-
grade x-ray, which is helpful for studying the motion in the esophagus. In
achalasia, barium swallows usually reveals an absence of contractions in the
esophagus after swallowing. Sometimes this test shows esophagus contracting
spastically in response to swallowing; this variation of achalasia is known as
vigorous achalasia.
After the barium swallow, you should drink extra fluid. Stools may be light in
color for a few days after testing as a result of the barium.
Manometry — Manometry refers to the measurement of pressure within the
esophagus and the LES. Pressures are measured by advancing a thin tube through
- the mouth or nose into the esophagus. The test is done after having nothing to eat
or drink for eight hours, while you are awake. You will be asked to swallow while
the tube is in place.
Manometry is always used to confirm achalasia. The test typically reveals thre e
abnormalities in people with achalasia: high pressure in the LES at rest, failure of
the LES to relax after swallowing, and an absence of useful (peristaltic)
contractions in the lower esophagus. The last two features are the most important
and are required to make the diagnosis.
Endoscopy — Endoscopy allows the physician to see the inside of the esophagus,
LES, and stomach using a thin, lighted, flexible tube. Endoscopy is done while
you are sedated. This test is usually recommended for people with suspe cted
achalasia and is especially useful for detecting other conditions that mimic
achalasia.
In people with achalasia, endoscopy often reveals abnormal changes in the
esophagus and food that has become stuck; it may also reveal inflammation, small
ulcers caused by residual food or pills, and candida (yeast) infection.
The endoscope can be advanced through the LES and into the stomach to check
for stomach cancer. Cancer in the upper part of the stomach can produce
symptoms almost identical to those of achal asia, and is called pseudoachalasia
(meaning "false" achalasia). Thus, biopsies (small samples of tissue) are often
- obtained in the lower portion of the esophagus. Having a biopsy while sedated is
not painful and is safe.
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