Achalasia--a disease of unknown cause that is often diagnosed too late

Abstract

Introduction: Many physicians are inadequately familiar with the clinical features of achalasia. Often, it is not diagnosed until years after the symptoms arise. This is unfortunate, because a delay in diagnosis worsens the prognosis.

Methods: Selective review of the literature.

Results: Achalasia has a lifetime prevalence of 1:10 000. It is a neurodegenerative disorder in which the neurons of the myenteric plexus are lost, leading to dysfunction of the lower esophageal sphincter and to a derangement of esophageal peristalsis. In the final stage of achalasia, esophageal motility is irreversibly impaired, and complications ensue because of the retention of food that is no longer transported into the stomach. Aspiration causes pulmonary disturbances in up to half of all patients with achalasia. There may also be inflammation of the esophageal mucosa (retention esophagitis); this, in turn, is a risk factor for esophageal cancer, which arises in 4% to 6% of patients. The cause of achalasia is not fully known, but autoimmune processes appear to be involved in patients with a genetic susceptibility to the disease.

Conclusion: Achalasia should be diagnosed as early as possible, so that complications can be prevented. In addition, guidelines should be established for cancer prevention in achalasia patients. Currently ongoing studies of the molecular causes of achalasia will probably help us understand its pathophysiology.

Figure

As a rule, endoscopy is the first step in diagnosing the cause of dysphagia. It can also be used to rule out secondary achalasia, e.g. inflammation, stenosis, or tumors, and to obtain tissue biopsies. However, if there are grounds in the patient’s medical history for suspecting a stricture, e.g. caused by radiation or chemical burns, a barium swallow and X-ray of the esophagus are recommended first, as endoscopy poses a higher risk of perforation. In such cases, endoscopy is performed only to rule out secondary achalasia. Once secondary achalasia has been ruled out endoscopically, an esophageal manometry and/or barium swallow and X-ray of the esophagus are performed

Figure 2

Characteristic X-ray of achalasia patient following barium swallow, with bird’s beak. At an advanced stage of achalasia, esophageal dilatation can be seen even on a chest X-ray with no contrast

Figure 3

Manometry results in achalasia: increased resting tone of LES with absence of relaxation on swallowing and simultaneous contractions of the tubular esophagus; “W” indicates a wet swallow. The manometry probe can measure the amplitude of esophageal contractions at three different locations in the tubular esophagus (top three sections); the bottom section provides a direct representation of the region of the lower esophageal sphincter (absence of relaxation). The y-axis shows the pressure in mm Hg, and the x-axis the time in second