You are currently viewing Achard Syndrome :‎ Medical Notes & Mindmap

Achard syndrome is a rare genetic disorder characterized by severe intellectual disability and abnormal growth. Affected individuals typically have small heads, delayed development, and distinctive facial features.

Achard Syndrome :‎ [MEDNOTES+MINDMAP]

  • Definition

    • Achard Syndrome is a rare genetic disorder characterized by the underproduction of thyroid hormones (hypothyroidism) and an enlarged thyroid gland (goiter).
  • Epidemiology

    • The prevalence of Achard Syndrome is unknown.
    • It is inherited in an autosomal recessive pattern, meaning that an individual must inherit two copies of the mutated gene (one from each parent) to develop the condition.
  • Natural history

    • Symptoms typically present at birth or within the first few weeks of life.
    • Untreated, Achard Syndrome can lead to severe developmental delays and complications such as heart problems and respiratory infections.
    • With early diagnosis and treatment, most individuals with Achard Syndrome can have a normal lifespan and reach their full developmental potential.
  • Classification/Types/Stages

    • Achard Syndrome is classified as a type of hypothyroidism.
    • There are no specific types or stages of Achard Syndrome.
  • Risk Factors:

    • Genetic predisposition
    • Environmental factors (such as exposure to toxins or infections)
    • Pregnancy or childbirth complications
  • Etiology/Causes:

    • Mutations in the PTPN11 gene
    • Abnormalities in the RAS/MAPK signaling pathway
  • Signs:

    • Delays in growth and development
    • Physical abnormalities, such as wide set eyes, low set ears, and a small head size
    • Cognitive and developmental delays
    • Seizures
  • Symptoms:

    • Poor muscle tone
    • Feeding difficulties
    • Breathing problems
    • Heart defects
    • Vision problems


  • Achard syndrome is caused by mutations in the PTPN11 gene, which codes for a protein called SHP2. This protein plays a role in the RAS/MAPK signaling pathway, which is important for the development of various organs and tissues.
  • Abnormalities in the RAS/MAPK signaling pathway can lead to abnormal development and function of various organs and tissues, resulting in the signs and symptoms of Achard syndrome.
  • Diagnosis/Laboratory Diagnosis
    • Identified through genetic testing
    • Can be confirmed with imaging studies, including brain MRI and CT scan
  • Tests Required
    • Genetic testing for mutations in the EI24 gene
    • Brain imaging studies to confirm diagnosis
  • Associated with
    • Intellectual disability
    • Delays in developmental milestones
    • Abnormal brain structure
  • Similar diseases/syndromes
    • Rett syndrome
    • Angelman syndrome
    • Cri du Chat syndrome
  • Treatment
    • No specific treatment for Achard syndrome
    • Supportive care and management of symptoms and associated conditions
    • Physical, occupational, and speech therapy
    • Educational and behavioral interventions as needed

Dr. Arin Nandi

Passionate About Medical Science & Helping Future Doctors Achieve Top Ranks In Medical Exams. He is professionally a dentist as well as a public health expert from JIPMER working in department