Allan-Herndon-Dudley Syndrome (AHDS)

What is Allan-Herndon-Dudley syndrome?

Allan-Herndon-Dudley syndrome (AHDS) is a brain development disorder that causes severe intellectual disability and movement problems almost exclusively in males. This condition disrupts development from even before birth.

What causes Allan-Herndon-Dudley syndrome?

AHDS is caused by mutations in the SLC16A2 gene, which is a gene that affects brain development, and these mutations are inherited in an X-linked recessive manner.

What are the symptoms of Allan-Herndon-Dudley syndrome?

Besides the intellectual disability and problems with movement that are characteristic of the disease, patients with AHDS also have the following symptoms:

Impaired speech and limited communication abilities
Weak and underdeveloped muscle tone
Joint deformities
Abnormal muscle stiffness and involuntary movements
Bowel incontinence

How is Allan-Herndon-Dudley syndrome diagnosed?

AHDS is diagnosed using the patient’s medical history, an evaluation of his symptoms, a physical exam, and laboratory tests. Some of these laboratory tests include:

Molecular genetic testing
Thyroid-hormone serum level tests

What are the available treatments for Allan-Herndon-Dudley syndrome?

Currently, there are no established treatments for AHDS, though the effect of Triac, a natural non-classical thyroid hormone, is currently under investigation. Management of the condition consists of supportive measures, such as physical, occupational, and speech therapy.