Down’s syndrome is one of the most common chromosomal disorders in pediatric practice(1). The most common thyroid disorder with Down’s syndrome is hypo-thyroidism(2)

An 8-year-old boy of Down’s syndrome was referred to the Endocrine clinic with weight loss of three kilograms, irritability, change in behavior and restlessness. At presentation the child was irritable and restless, unable to sit still. He had up slanting eyes, epicanthic folds, high arched palate and protruding tongue. His height was 128 cm (90th percentile by the Indian Council Medical Research charts)(3). The weight was 20 Kg [50th percentile by ICMR charts]. He had a visible goiter, a bruit over the thyroid, exophthalmos and mental retardation. The mental age was 3.4 years. The serum Total Thyronine (T3) was 320 ng/dL (normal 55-180 ng/dL), Serum Thyroxin (T4) was 16 (µg/dL (normal 5.5-11(µg/dL). The Serum Thyrotropin (Serum TSH) was undetectable by third generation Immuno Radiometric assay. The radioiodine I131 uptakes at two hours was 76% and at twenty-four hours was 91.6%. Thyroid scan using Tc99 showed a diffuse uptake. The thyroid antimicrosomal antibody titers were not raised. He was treated initially with carbimazole 15 mg/day and propranolol 20 mg/day. There was symptomatic improvement after six weeks of treatment. The antithyroid drugs were continued for a period of eighteen months with regular monitoring of the thyroid function. There was a gain in weight by 7 Kg from the pre treatment weight. The child responded with clinical and biochemical remission after 18 months of treatment with carbimazole. The child has maintained remission on subsequent follow up for six months.

Thyroid disorders are common in Down’s syndrome. The anti thyroid auto antibodies are found in 13 to 34% of patients of Down’s syndrome(2) Hypothyroidism due to auto-immune thyroiditis is the most common thyroid disorder. Hyperthyroidism is rare in the patients of Down’s syndrome and the reported incidence of hyperthyroidism varies from 0.07- 2.5%. It rarely presents before eight years of age(4). The treatment is with a beta blocking agent such as propranolol, 1mg/kg/day in divided doses, and an antithyroid drug started at the same time. Carbimazole 0.5 to 1.0 mg/kg/day is given till the time remission is achieved(5). Our patient had Down’s syndrome developed Graves disease that responded well with medical treatment. The rarity of this association especially in a male at eight years of age has prompted us to report this case. We recommend that thyroid function be followed closely in all the patients of Down’s syndrome.

Abhay I. Ahluwalia,
Shankar Narayan,
Correspondence to:
Surg Commander Abhay I. Ahluwalia,
Classified Specialist,
Medicine & Endocrinology,
INHS Asvini,
Colaba, Mumbai 400 005, India.
E-mail: [email protected]

1. Jain R, Thomasma DC, Ragas R. Down syndrome: still a social stigma. Am J Perinatol 2002 19: 99-108.

2. Loudon MM, Day RE and Duke EM Thyroid dysfunction in Down’s syndrome Arch Dis Childh, 1985; 60 : 1149-1151.

3. Technical Report Series No 18 ;Growth and Development of Indian Infants and Children: Indian Council of Medical Research Publication; 1989; pp. 61-136.

4. Karlsson B, Gustafsson J, Hedov G, Ivarsson SA, Anneren G. Thyroid dysfunction in Down’s syndrome: Relation to age and thyroid autoimmunity. Arch Dis Child 1998 ; 79: 242-245.

5. Annotation Treatment of hyperthyroidism in young people Arch Dis Child 1998; 78: 207-209.