DEFINITION
Achalasia is a relatively rare disorder of the smooth mucosa of the esophagus. The esophagus is a muscular tube that carries food and liquids from the mouth to the stomach. Achalasia makes it difficult for it to pass into the stomach from the esophagus.
CAUSES
There is a muscle called the lower esophageal sphincter (LES) where the esophagus joins the stomach. When you're not swallowing, the LES stays closed to prevent food, fluids, and stomach acid from backing up through the esophageal tube. When you swallow, nerve signals tell the muscles to contract to push the food down the esophagus (this action is called peristalsis) and allow the LES to open. In people with achalasia, the nerve cells in the lower esophageal tube and in the LES they work right. This results in:
- Absent peristaltic (muscular) activity
- Failure of the LES to fully open
While achalasia is associated with nerve cell loss in the esophagus, the cause of this process is unknown.
RISK FACTORS
A risk factor is something that increases your chance of getting a disease or condition. Because the exact cause of achalasia is unknown, the risk factors are also unknown.
SYMPTOMS
Symptoms of achalasia can appear between the ages of 25 and 60. Symptoms rarely develop in children. These symptoms tend to be mild at first and then worsen over months or years. The main symptom is difficulty swallowing solids and, as the disorder progresses, liquids. Between 70% and 97% of patients with achalasia have difficulty swallowing both solids and liquids. Other symptoms may include:
- Chest discomfort or pain (below the breastbone, especially after eating)
- Cough, especially when lying down
- Heartburn
- Weight loss (as the disorder progresses)
- Vomiting or regurgitation of solids or liquids. In some people, this occurs during sleep. This can lead to the inhalation of solid or liquid particles, which can cause aspiration pneumonia and other respiratory infections.
DIAGNOSIS
The doctor will ask about your symptoms and medical history, and perform a physical exam. Tests may include:
- Manometry: This involves inserting a tube down the throat to measure the pressure inside the esophagus and stomach when swallowing.
- Esophagram: X-rays of the esophagus are taken when you swallow barium (a thick liquid that lights up on x-rays).
- Upper gastrointestinal endoscopy (esophagoscopy): The esophagus is viewed directly through a fiberoptic tube to check for other causes of symptoms.
TREATMENT
The goal of treatment is to make it easier for the LES to open. Treatment may include:
Pneumatic Expansion
This treatment stretches the LES muscle. A thin tube is inserted into the throat. At the end of the tube is a deflated balloon. Once the tube reaches the LES muscle, the balloon is inflated. Pneumatic dilatation has a high success rate. It is the primary treatment for most patients, although it may need to be repeated.
Botulinum Toxin
Minimal amounts of botulinum toxin type A are injected into the LES. The botulinum causes it to relax, making it easier to open. Because the effect is temporary, it is necessary to repeat the injections, but the positive reaction decreases with the frequency of the injection.
Surgery
Small incisions are made in the LES to allow relaxation. This is called Heller myotomy surgery. This is usually done via laparoscopy, which makes it a relatively minor surgical procedure. Because a partial cut is made in the LES, approximately 15% of patients experience symptoms of gastroesophageal reflux (ie, acid reflux) after this procedure.
Medicines
In mild cases, certain medications can help relieve symptoms temporarily. Medicines that reduce pressure in the LES include:
- Nifedipine
- Nitroglycerine
PREVENTION
There is no guide to prevent achalasia because its causes are usually unknown.