Prevalence of incidental thyroid disease in a relatively low iodine intake area.
An ultrasonographic survey of thyroid abnormalities was conducted in 547 consecutive apparently normal overweight subjects (380 females and 167 males), aged 27-58 years in an urban area with relatively low iodine intake (mean daily urinary iodine excretion: 10.6 micrograms/dL). Individuals with any previous thyroid disease or familial thyroid pathology were excluded. In 240 subjects (44%) high resolution ultrasonography of the thyroid was considered normal. In 307 individuals (56%) abnormalities of the echo structure (39%) or thyroid nodular disease (17%) were detected by ultrasonography. Marked heterogeneity of the echo structure that was considered suggestive of chronic autoimmune thyroiditis was present in 81 subjects (15%). In 72 of these patients the serum anti-TPO levels were positive by a sensitive RIA. Thyroid nodules either solid or predominantly cystic were present in 90 subjects (17%). Eighteen patients had a relatively large nodule (diameter 15-18 mm). Eleven of these nodules were missed at clinical examination. Fine needle aspiration cytology was performed in 14 patients and 7 individuals underwent thyroid surgery. In 6 subjects the pathologic diagnosis was benign adenomatous goiter and one patient had a follicular carcinoma. Thyroid function studies confirmed subclinical hypothyroidism in 27 patients (4.9%), all of them with elevated serum anti-TPO autoantibodies levels. It was concluded that the overall occurrence of thyroid disease is more common than suspected by clinical examination.
D000293:Adolescent; D000328:Adult; D000368:Aged; D001323:Autoantibodies / Q000097:blood; D001707:Biopsy, Needle; D001938:Brazil / Q000453:epidemiology; D005260:Female; D006801:Humans; D007453:Iodide Peroxidase / Q000276:immunology; D007455:Iodine / Q000008:administration & dosage*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D013959:Thyroid Diseases / Q000000981:diagnostic imaging / Q000453:epidemiology*; D013961:Thyroid Gland / Q000000981:diagnostic imaging* / Q000473:pathology; D016606:Thyroid Nodule / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000473:pathology; D013967:Thyroiditis, Autoimmune / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000276:immunology; D014463:Ultrasonography
D001323:Autoantibodies; D007455:Iodine; D007453:Iodide Peroxidase