RESUMO
The prevalence of antithyroperoxidase antibodies in 40 infants and children with Down syndrome was determined and compared with their prevalence in 40 healthy children. The association of antithyroperoxidase antibodies and thyroid dysfunction in this group of Down syndrome patients was also studied. Twenty-six Down syndrome patients were positive for antithyroperoxidase antibodies; while in the control group, only 6 were positive. Thirteen Down syndrome patients had subclinical hypothyroidism, i.e. normal T4 and raised TSH [>5 ml U/ml]. Eight of them were positive for antithyroperoxidase antibodies. In the control group, five patients had sub-clinical hypothyroidism and two patients were positive for antithyroperoxidase antibodies. This supported the observation that the most frequently observed thyroid abnormality appears to be subclinical hypothyroidism in patients with Down syndrome