Thyroid status of iodine deficient newborn infants living in central region of Turkey: a pilot study

• Published in: World journal of pediatrics : WJP Vol. 13; no. 5; pp. 479 - 484
• Main Authors: Bastug, Osman, Korkmaz, Levent, Halis, Hulya, Memur, Seyma, Korkut, Sabriye, Ozdemir, Ahmet, Gunes, Tamer, Ozturk, Mehmet Adnan, Kurtoglu, Selim
• Format: Journal Article
• Language: English
• Published: Hangzhou Childrens Hospital, Zhejiang University School of Medicine 01.10.2017; Division of Neonatology, Department of Pediatrics,Erciyes University Medical Faculty, Talas Street, Kayseri, Turkey%Department of Neonatology, Erciyes University Medical Faculty, Kayseri, Turkey
• Subjects: Critical Care Medicine; Deficiency Diseases - blood; Deficiency Diseases - diagnosis; Female; Humans; Imaging; Infant, Newborn; Intensive; Iodine - deficiency; Male; Maternal and Child Health; Medicine; Medicine & Public Health; Original Article; Pediatric Surgery; Pediatrics; Pilot Projects; Radiology; Surgery; Thyrotropin - blood; Thyroxine - blood; Triiodothyronine - blood; Turkey; infant; thyroid function; hypothyroidism
• ISSN: 1708-8569; 1867-0687
• DOI: 10.1007/s12519-017-0017-6

Background Iodine deficiency (ID) during the fetal and neonatal periods can lead to neonatal hypothyroidism. This study was conducted to evaluate the effect of ID on the thyroid hormone level of newborns living in Turkey. Methods Between 1998 and 2013, 71 newborns with a urinary iodine concentration <100 μ g/L were recruited into the study. Data on thyroid volume, free triiodothyronine (fT3), free thyroxine (fT4), thyroid stimulating hormone (TSH), and thyroglobulin (Tg) were collected from all newborns, and on breast milk iodine from their mothers. Infants who were classified as having congenital hypothyroidism (TSH >40 mU/L and fT4 <8.5 pmol/L) were treated with levothyroxine ( n =26, T group), while the remaining infants remained untreated ( n =45, UT group). Thyroid hormones were subsequently measured 7-14 days later in a sub-sample of both treated and untreated infants. Results The average values at the time of admission were as follows [median (min-max)]. fT3: 5.0 (2.8-7.1) pmol/L, fT4: 7.7 (0.13-19.1) pmol/L, TSH: 75 (14-426) mU/L, Tg: 464 (226-1100) ng/mL, urinary iodine concentration (UIC): 30 (0-61) μ g/L, breast milk iodine levels: 21 (10-150) μ g/L, thyroid ultrasound (USG): 1.10 (0.24-1.95) mL for the T group; and fT3: 5.7 (1.7-12.7) pmol/L, fT4: 16.2 (9.9-33.5) pmol/L, TSH: 5.4 (0.63-41.8) mU/L, Tg: 171 (15-2124) ng/mL, UIC: 39 (0-90) μ g/L, breast milk iodine levels: 47 (10-120) μ g/L, thyroid USG: 0.75 (0.35-1.72) mL for the UT group. A significant difference was found between groups in respect to fT3, fT4, TSH and Tg levels. No significant difference in thyroid ultrasonography, UIC, and breast milk iodine levels was found between the two groups. The Tg levels of 50 out of 71 patients were measured, 40 (80%) of whom had Tg levels above the normal range (101 ng/mL). Conclusions In our country, despite the use of iodized salt, congenital hypothyroidism due to ID remains a problem. The Tg level of newborns can be used as a good indicator of ID.