Achalasia is failure of the lower esophageal sphincter to relax. This is due to decrease in the number or absence of Auerbach’s myenteric plexus ganglion cells in the distal esophagus. Although a more thorough differential diagnosis list can be found elsewhere in this report (Eisenberg, p. 11), it should be mentioned that idiopathic or primary achalasia is the most common cause of this disease.

Secondary achalasia (functional obstruction secondary to destruction of the myenteric plexus by a paraneoplastic process) presents with an identical picture. Pseudoachalasia describes true mechanical obstruction or narrowing of the distal esophagus by tumor (i.e., not functional obstruction).

Symptoms of achalasia include dysphagia and weight loss. Pain is less common (as compared to esophageal spasm in which pain is frequently present). Dysphagia for both solids and liquids is generally present, and regurgitation of food material may occur. Complications include aspiration and subsequent pneumonia, weight loss, and nutritional deficiencies.

Most cases of primary (idiopathic) achalasia present in patients aged 20 to 40 years old. Esophageal manometry is the diagnostic study of choice. Other diagnostic tests involving amyl nitrate, mecholyl, and the ingestion of Seidlitz powder are sometimes employed.

Plain radiographs of the chest can demonstrate retention of food and fluid within the esophagus (which is often dilated). An air-fluid level may be present. Evidence of chronic or acute aspiration pneumonia can be seen.

Barium esophogram findings include ineffective or uncoordinated primary stripping waves and/or tertiary contractions with failure of the lower esophageal spincter (LES) to relax (demonstrated by retention of barium above the LES for longer than 2.5 sec after swallowing). Smooth tapering of the distal esophagus forming a rat-tail or bird’s beak appearance is a characteristic finding. Even in the upright position, the esophagus only poorly empties (as compared to scleroderma in which the esophagus usually empties in a more normal fashion when the patient is upright).

Eisenberg discusses findings which may help to distinguish between achalasia and pseudoachalasia. Benign achalasia is more likely to present in patients less than 40 years of age and in persons who have had symptoms for more than a year. Melena is not common in benign disease states. The esophagus tapers more gradually in benign achalasia whereas a more abrubt transition from normal to abnormal esophagus is more typical of pseudoachalasia. Obviously, the presence of a discrete mass or evidence of mass effect (contour deformities) favors a malignant process. Diffuse neuromuscular abnormality favors benign disease as does some degree of retained pliability.

Treatment options include nitrates, beta agonists, and calcium channel blockers. Ballon dilatation (balloon myotomy) is a more effective treatment than medication, and surgical myotomy (Heller myotomy) is also an option. The most feared complication of balloon dilatation is esophageal perforation, and complications of surgical myotomy include subsequent gastroesophageal reflux disease and the eventual possibility of esophagitis or stricture.