Down syndrome (DS) is associated with an increased risk of multisystemic dysfunction, namely endocrine abnormalities. Thyroid dysfunction is the most common endocrinological disorder, and it can manifest as either hypothyroidism or hyperthyroidism. A 16-year-old patient with DS developed hyperthyroidism after a lifetime of alternating between subclinical hypothyroidism and euthyroidism. He presented new onset weight loss, agitation and diarrhoea. Laboratory studies were compatible with hyperthyroidism. Thyroid receptor antibodies (TRAbs) were positive, antithyroid peroxidase antibodies and thyroglobulin antibodies were negative. Antithyroid medication (methimazole) was prescribed and, despite therapy adjustments, laboratory evaluation revealed new onset hypothyroidism with persistently positive TRAbs. He experienced weight gain and remained in a hypothyroid state even with withdrawal of methimazole and administration of levothyroxine. This case illustrates an example of Graves’ disease with coexisting stimulating and inhibiting TRAbs that led to a shift from hyperthyroidism to hypothyroidism, a rare condition in patients with DS.
- thyroid disease
Statistics from Altmetric.com
Contributors The author STBC did the research, analysed the data and wrote the first draft of the manuscript. The author VA revised the content and added relevant information. The author PF analysed the scientific content and corrected and partially rewrote the article. The author AP provided critical revision of the article. All authors provided final approval of the version to publish.
Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.
Competing interests None declared.
Provenance and peer review Not commissioned; externally peer reviewed.
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.