Thyroid Disorder


Thyroid function in the neonatal period

  • An estimated 1% of babies with Down syndrome have a raised TSH on newborn screening, but classical congenital hypothyroidism due to thyroid dysgenesis is not common.
  • Raised TSH should prompt further investigation, and consideration of treatment with thyroxine.
  • Borderline thyroid dysfunction in the neonate may be transient, and when treatment is started in these cases , treatment should be stopped after the age of 2 years and thyroid function reassessed off treatment.
  • At present there is no hard evidence to justify routinely treating infants with Down syndrome with thyroxine, if they have normal thyroid function.

Thyroid function beyond the neonatal period

  • Thyroid dysfunction , mainly hypothyroidism occurs more commonly in people with Down syndrome at all ages, when compared with the general population.
  • The prevalence of autoimmune thyroiditis increases with age in Down syndrome.
  • Clinical diagnosis of hypothyroidism may be unreliable in Down syndrome because of overlap with features commonly seen in the syndrome e.g. dry skin, thin hair and constipation.
  • Screening for thyroid dysfunction is required throughout life.
  • Capillary TSH testing is a practical reliable method. This can be done by fingerprick samples and on the same cards as used for newborn screening.
  • Mild elevation of TSH with normal fT4 and no symptoms may not require treatment.
  • Hyperthyroidism is less common than hypothyroidism, but occurs more frequently than in the general population.

DSMIG Guidance


Thyroid Disorder in Children and Young People with Down Syndrome
Surveillance and when to initiate treatment

Appendices: Thyroid Disorder in Children and Young People with Down Syndrome

Thyroid Disorder In CYP With Down Syndrome Surveillance And When To Initiate Treatment April 2020
Powerpoint presentation (22.05.2020)

Flow charts

Neonatal Screening

Ongoing Surveillance (from 4 6 Months Age)

Child Young Person With A Goitre

Marginally Abnormal Initial Venous Blood Testing Findings

Abnormal Initial Venous Blood Tests Requiring Immediate Action)

Audit tool (Excel file)

15.8.20 Blank Thyroid Audit Tool DSMiG

Last updated: October 2020

Presentations at DSMIG Meetings

Materials from meetings are available for members only who need to log in to access them. For details on how to become a member click here.

Additional Resources

Thyroid Disorder – Down’s syndrome association health series 

Updated 2020

Book Chapter –  Endocrine Disorders – Thyroid Disorder

Malcolm Donaldson and Kath Leyland

in Down Syndrome – Current Perspectives

Edited by Richard Newton , Shiela Puri and Liz Marder