title: Evaluation of thyroid functions with respect to iodine status and TRH test in chronic autoimmune thyroiditis.
abstract: OBJECTIVE
  Chronic autoimmune thyroiditis (CAT) is the most common form of thyroiditis in childhood and a frequent cause of acquired hypothyroidism. The objective of this study was to evaluate the thyroid status of children and adolescents with CAT with respect to iodine status and diagnostic values of thyrotropin-releasing hormone (TRH) test.
  
  
  METHODS
  Seventy-one children (mean age: 11.6 years) were studied in a retrospective analysis. Free thyroxine (T4), thyrotropin (TSH), TSH response to TRH test, thyroid autoantibodies, thyroid sonography, and urinary iodine excretion (UIE) were evaluated.
  
  
  RESULTS
  At diagnosis, 8.5% of patients had overt hypothyroidisim and 36.6% subclinical hypothyroidism; 5.6% had overt hyperthyroidisim and 8.5% had subclinical hyperthyroidism. Of them, 40.8% were euthyroid. Median UIE was 51 mg/L in overt hypothyroidism and 84 mg/L in subclinical hypothyroidism. The values were 316 mg/L and 221 mg/L in overt and subclinical hyperthyroidism, respectively. Basal TSH showed a strong correlation with peak TSH level on TRH test. Thirty-four percent of patients with normal basal TSH level showed an exaggerated TSH response.
  
  
  CONCLUSIONS
  Iodine deficiency was seen more in cases with hypothyroidism, while excess of iodine was observed to be more frequent in hyperthyroid patients. Iodine status was a strong predictorof the thyroid status in CAT. TRH test may be helpful in further delineating patients with subclinical hypothyroidism.
authors: Ufuk University School of Medicine, Department of Pediatric Endocrinology, Ankara, Turkey. aycaergur@superonline.com
authors: Ayça Törel
authors: AT
authors: Ergür
authors: Olcay
authors: O
authors: Evliyaoğlu
authors: Zeynep
authors: Z
authors: Şıklar
authors: Pelin
authors: P
authors: Bilir
authors: Gönül
authors: G
authors: Öcal
authors: Merih
authors: M
authors: Berberoğlu
mesh_terms: D000293:Adolescent; D002648:Child; D005260:Female; D050031:Hashimoto Disease / Q000175:diagnosis; D006801:Humans; D007455:Iodine / Q000378:metabolism*; D008297:Male; D012189:Retrospective Studies; D013963:Thyroid Hormones / Q000097:blood*; D013966:Thyroiditis; D013967:Thyroiditis, Autoimmune / Q000097:blood / Q000175:diagnosis*; D013973:Thyrotropin-Releasing Hormone
chemical_list: D013963:Thyroid Hormones; D013973:Thyrotropin-Releasing Hormone; D007455:Iodine