Achalasia is a rare disorder of the food pipe (oesophagus), which can make it difficult to swallow food and drink.
Normally, the muscles of the oesophagus contract to squeeze food along towards the stomach. A ring of muscle at the end of the food pipe then relaxes to let food into the stomach.
The upper esophageal sphincter is a muscular valve that is located at the upper portion of the esophagus, which is typically about 8 inches long.
Unlike the lower esophageal sphincter (LES), which opens and closes without our conscious effort, the upper esophageal sphincter is under our conscious control. We can control when it opens. For example, we can open the upper esophageal sphincter by swallowing foods or liquids.
In achalasia however, there is a failure of organized esophageal peristalsis causing impaired relaxation of the lower esophageal sphincter, and resulting in food stasis and often marked dilatation of the esophagus.
Obstruction of the distal esophagus from other non-functional etiologies, notably malignancy, may have a similar presentation and have been termed “secondary achalasia” or “pseudoachalasia“.
SYMPTOMS
Patients may present with:
- dysphagia for both solids and liquids: this is in contradistinction to dysphagia for solids only in cases of esophageal carcinoma
- chest pain/discomfort
- eventual regurgitation
- drooling of vomit or saliva
- gradual but significant weight loss
CAUSES
Almost thought to be familial, but is also thought to happen when the nerves in the oesophagus become damaged and stop working properly, which is why the muscles and ring of muscle don’t work. It could also be as a result of the body’s immune system attacking healthy cells (autoimmune condition).
PATHOLOGY
“Peristalsis in the distal smooth muscle segment of the esophagus may be lost due to an abnormality of the” Auerbach plexus” (responsible for smooth muscle relaxation), resulting in weak, uncoordinated contractions that are non-propulsive”. The abnormality may also occur in the vagus nerve or its dorsal motor nucleus.
The lower esophageal sphincter eventually fails to relax, either partially or completely, with elevated pressures demonstrated manometrically . Early in the course of achalasia, the lower esophageal sphincter tone may be normal or changes may be subtle.
TREATMENT OPTIONS
MEDICATION: Medicines like nitrates or nifedipine can help relax the muscles in your oesophagus and make swallowing less painful and difficult.
Botox injection and balloon dilation could also be useful.
DIETARY MANAGEMENT
The management of the patient with achalasia and nutritional problems is very similar to that of patients with dysphagia due to neurologic disease or esophagogastric cancer. Oral feeding has relevant psychosocial significance to patients and their families, and should be continued whenever possible. In some patients, oral intake is often not adequate even in the absence of significant swallowing difficulties. In mild to moderate achalasia, nutrition is generally mildly affected and, if the family encourages the patient to follow dietary modifications, loss of weight and malnutrition rarely occurs.
Dysphagia diets should be highly individualized, including modification of food texture or fluid viscosity. Food may be chopped, minced, or puréed, and fluids may be thickened.
If a patient is unable to eat or drink or to consume sufficient quantities of food, or the risk of pulmonary aspiration is high, tube feeding should be provided. If there is a possibility for surgical myotomy, enteral nutrition via a nasal feeding tube will be adequate as a provisional measure, considering that a malnourished patient is always at major risk for postoperative complications.
SOURCES : https://www.nhs.uk/conditions/achalasia/
https://radiopaedia.org/articles/achalasia
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3108680/
