Triple A syndrome

Achalasia is a disorder of the esophagus, the tube that carries food from the mouth to the stomach. It is characterized by enlargement of the esophagus, impaired ability of the esophagus to push food down toward the stomach (peristalsis), and failure of the ring-shaped muscle at the bottom of the esophagus (the lower esophageal sphincter) to relax.^[1] Achalasia is typically diagnosed in individuals between 25 and 60 years of age. The exact etiology is unknown, however, symptoms are caused by damage to the nerves of the esophagus.^[2] Familial studies have shown evidence of a potential genetic influence. When a genetic influence is suspected, achalasia is called familial esophageal achalasia. Treatment is aimed at reducing the pressure at the lower esophageal sphincter and may include Botox, medications, or surgery.^[3]

Most individuals with triple A syndrome develop achalasia. It usually develops during childhood or adolescence, although in some cases it does not occur until early adulthood.^[4]

Many of the neurological features of triple A syndrome are caused by dysfunction of the autonomic nervous system. This part of the nervous system controls involuntary body processes such as digestion, blood pressure, and body temperature. People with triple A syndrome often experience abnormal sweating, difficulty regulating blood pressure, unequal pupil size (anisocoria), and other signs and symptoms of autonomic nervous system dysfunction (dysautonomia).^[4]

People with this condition may have other neurological abnormalities, such as developmental delay, intellectual disability, speech problems (dysarthria), and a small head size (microcephaly). In addition, affected individuals commonly experience muscle weakness, movement problems, and nerve abnormalities in their extremities (peripheral neuropathy). Some develop optic atrophy, which is the degeneration (atrophy) of the nerves that carry information from the eyes to the brain.^[4]

Most of the neurologic features of triple A syndrome begin during adulthood, and they often worsen over time.^[4]