Achalasia is the idiopathic motility disorder characterized by incomplete relaxation of the Lower Esophageal sphincter (LES) in response to swallowing. This is a functional esophageal obstruction.
Recall that the muscles of the esophagus are as follows: Upper third consist of striated muscle, the idle one third consist a mixture of striated and smooth muscle, and the lower one third consist of smooth muscles, innervated by the myenteric plexus that coordinate the peristalsis of esophagus during swallowing.
Etiology and Associations
Table of Contents
Primary is idiopathic – Due to damaged ganglion cells in the myenteric plexus that are important for regulating bowel motility and relaxing the lower esophageal sphincter (LES). This leads to loss of intrinsic inhibitory innervations of LES and smooth muscles. The result is a loss of nitric oxide producing inhibitory neurons in the myenteric plexus.
Secondary achalasia (Pseuodoachalasia) are achalasia that has a clear cause. They can be caused by infections such as (Chagas’s disease, Polio). Other infiltrative disease like amyloidosis, Sarcoidosis, Neoplasm (often Squamous cell carcinoma of esophagus, lymphoma). A complete list of potential causes of achalasia include
- Infectious causes (Chagas disease, Polio)
- Infiltrative disease Amyloidosis, Sarcoidosis, Neoplasm (lymphoma or esophageal carcinoma)
- Others (Neurofibromatosis, Eosinophilic esophagitis, MEN 2B syndrome, Juvenile Sjögren syndrome)
Symptoms and Clinical Presentation
Dysphagia for solid and liquids at same time, Odynophagia (painful swallowing) chest pain like symptom. Weight loss, putrid breath, vomiting/regurgitation of eaten material (increases risk for aspiration pneumonia)
Diagnosis
The initial diagnosis for achalasia is Barium Esophagram: Patient with achalasia will appear as dilated esophagus with smooth “bird’s beak” narrowing at GEJ. It is important to note that cancer of the esophagus can look similar to achalasia and hence EGD may be indicated to rule out cancer and Barrett esophagus via biopsy during upper endoscopy. EGD is indicated if there is alarming symptom like weight loss, heme+ stool, more than 60 years old, more than 6 month of symptoms, anemia.
The most accurate diagnosis of achalasia is Manometry: Manometry will show high lower esophageal sphincter (LES) pressure at rest and incomplete relaxation of lower esophageal sphincter (LES) after swallow. Absence of peristalsis in the esophageal body is seen.
Chest X-Ray (CXR) will show widening of mediastinum
Progression and Complications:
Achalasia can have several complication although not very often. Some of the complication of achalasia include
- Increase risk for Esophageal squamous cell carcinoma (Esophageal web also Increase this)
- Increase risk for aspiration pneumonia.
Treatment and Management
Initial Management: #1 or #2
- Endoscopic Pneumatic dilation: effective in 85% of patient (3% of perforation)
- Surgical sectioning or myotomy can help alleviate symptoms: more effective than dilation but more dangerous (side effect of GERD). Because many develop GERD after surgery, most surgeons also perform an antireflux surgery called Nissen fundoplication and all patient are given proton pump inhibitors daily.
- Endoscopy guided injection of botulinum toxin injection directly into the LES will relax the LES but will wear off in 3-6 months. This is used when patient failed surgery or pneumatic dilation treatment or in those with comorbidity that make them a poor candidate for surgery of endoscopic pneumatic dilation.
