Achalasia is a motor disorder of the esophageal smooth muscle, characterized by partial or incomplete relaxation of the lower esophageal sphincter (LES) with swallowing, abnormal esophageal peristalsis, and increased resting tone of the LES. The underlying abnormality of primary achalasia involves the loss of intramural neurons of Auerbach's plexus in the smooth muscle portion of the esophagus and LES.

Causes of secondary achalasia include gastric carcinoma, lymphoma, and Chagas disease. In Chagas disease, Trypanosoma cruzi destroys the myenteric plexus of the esophagus, duodenum, colon, and ureter, causing subsequent dilation.
Achalasia typically manifests in young adulthood but may appear at any age.

Classic symptoms include dysphagia of both solids and liquids, chest pain, and regurgitation. There is retention of large volumes of saliva and ingested food in the esophagus, and aspiration can occur.

The classic diagnostic findings include esophageal dilatation and a bird's beak appearance of the terminal esophagus with a barium swallow study. On fluoroscopy, normal peristalsis is absent in the lower two-thirds of the esophagus. Manometry reveals a normal or elevated LES pressure with reduced or absent swallow-induced relaxation. Endoscopy is helpful in ruling out secondary causes of achalasia, particularly gastric carcinoma.


Treatment for achalasia involve both pharmacologic and nonpharmacologic therapies. Initial conservative management is the ingestion of soft foods. Medications that have been used include nitrates and calcium channel blockers (taken before meals), as well as botulinum toxin that acts by blocking cholinergic excitatory neurons in the sphincter. A commonly used nonpharmacologic therapy is ballon dilatation at the LES in order to reduce the basal LES pressure by tearing muscle fibers. This technique is effective in approximately 86% of patients. Myotomy of the sphincter has been used as well. Reflux esophagitis and peptic stricture may follow successful treatment with balloon dilatation or myotomy.