Triple-A syndrome

A rare autosomal recessive disorder

Triple-A syndrome, also known as Allgrove syndrome, is a rare autosomal recessive disorder characterized by the triad of achalasia, adrenal insufficiency, and alacrima. The condition is caused by mutations in the AAAS gene, which encodes the protein ALADIN, involved in nuclear pore complex function.

Signs and symptoms

A patient with Triple-A syndrome showing signs of alacrima and achalasia.

The hallmark features of Triple-A syndrome include:

• Achalasia: A condition where the lower esophageal sphincter fails to relax properly, leading to difficulty swallowing (dysphagia), regurgitation, and sometimes chest pain.
• Adrenal insufficiency: This results from the underproduction of adrenal hormones, particularly cortisol, leading to symptoms such as fatigue, muscle weakness, weight loss, low blood pressure, and hyperpigmentation of the skin.
• Alacrima: A lack of tear production, which can lead to dry eyes and increased risk of eye infections.

Additional symptoms may include neurological abnormalities, such as peripheral neuropathy, autonomic dysfunction, and cognitive impairment.

Genetics

Triple-A syndrome is inherited in an autosomal recessive pattern, meaning that an individual must inherit two copies of the mutated gene, one from each parent, to be affected. The AAAS gene is located on chromosome 12q13, and mutations in this gene disrupt the function of the ALADIN protein, affecting cellular processes.

Diagnosis

Diagnosis of Triple-A syndrome is based on clinical evaluation, family history, and genetic testing. The presence of the characteristic triad of symptoms often prompts further investigation. Genetic testing can confirm mutations in the AAAS gene.

Management

Management of Triple-A syndrome is symptomatic and supportive. Treatment may include:

• Hormone replacement therapy for adrenal insufficiency, typically with glucocorticoids and mineralocorticoids.
• Surgical or endoscopic intervention for achalasia, such as pneumatic dilation or Heller myotomy.
• Artificial tears and other measures to manage alacrima and protect the eyes.

Prognosis

The prognosis for individuals with Triple-A syndrome varies depending on the severity of symptoms and the effectiveness of treatment. With appropriate management, many individuals can lead relatively normal lives, although they may require ongoing medical care.

Related pages

• Achalasia
• Adrenal insufficiency
• Autosomal recessive disorder