Context The impact of Hashimoto thyroiditis (HT) on the risk of thyroid cancer and its accurate detection remains unclear. The presence of a chronic lymphocytic infiltration imparts a logical mechanism potentially altering neoplastic transformation, while also influencing the accuracy of diagnostic evaluation. Methods We performed a prospective, cohort analysis of 9851 consecutive patients with 21,397 nodules ≥1 cm who underwent nodule evaluation between 1995 and 2017. The definition of HT included (i) elevated thyroid peroxidase antibody (TPOAb) level and/or (ii) findings of diffuse heterogeneity on ultrasound, and/or (iii) the finding of diffuse lymphocytic thyroiditis on histopathology. The impact of HT on the distribution of cytology and, ultimately, on malignancy risk was determined. Results A total of 2651 patients (27%) were diagnosed with HT, and 3895 HT nodules and 10,168 non-HT nodules were biopsied. The prevalence of indeterminate and malignant cytology was higher in the HT vs non-HT group (indeterminate: 26.3% vs 21.8%, respectively, P < 0.001; malignant: 10.0% vs 6.4%, respectively, P < 0.001). Ultimately, the risk of any nodule proving malignant was significantly elevated in the setting of HT (relative risk, 1.6; 95% CI, 1.44 to 1.79; P < 0.001), and was maintained when patients with solitary or multiple nodules were analyzed separately (HT vs non-HT: 24.5% vs 16.3% solitary; 22.1% vs 15.4% multinodular; P < 0.01). Conclusion HT increases the risk of thyroid malignancy in any patient presenting for nodule evaluation. Diffuse sonographic heterogeneity and/or TPOAb positivity should be used for risk assessment at time of evaluation.

Background: Insufficient or excessive iodine intake during gestation may compromise adaptive mechanisms in maternal thyroid function and lead to adverse pregnancy outcomes. In this context, we aimed to study the effects of maternal iodine status in the first and third trimesters of gestation on obstetric and neonatal outcomes in an iodine-sufficient population in Rio de Janeiro, Brazil. Methods: A total of 214 pregnant women in the first trimester of gestation were enrolled and prospectively followed until delivery between 2014 and 2017. All participants were ‡18 and £35 years, had a spontaneous single pregnancy, and had no history of thyroid or other chronic diseases, nor were they taking iodinecontaining supplements at enrollment. In the first trimester, we obtained clinical information and determined thyroid function and the urinary iodine concentration (UIC) of the participants. Thyroid function and UIC were reassessed in the third trimester. Iodine status was determined by the median of UIC obtained from six urine spot samples by the inductively coupled plasma mass spectrometry method. Pregnancy and neonatal outcomes and delivery information were obtained from medical records. Results: The median UIC in the whole population was 219.7 lg/L. The prevalence of UIC <150 lg/L was 17.2%, and 38.7% had UIC ‡250 lg/L. Gestational diabetes (GDM) was higher in the group with UIC 250-499 lg/L (n = 77) compared with the group with UIC 150-249 lg/L (n = 94) (20.3% vs. 9.7%, p < 0.05). Ultimately, UIC ‡250 lg/L was an independent risk factors for GDM (relative risk [RR] = 2.9 [confidence interval, CI = 1.1-7.46], p = 0.027) and hypertensive disorders of pregnancy (HDP) (RR = 4.6 [CI = 1.1-18.0], p = 0.029). Among 196 live-born newborns, lower birth length was observed in infants whose mothers had UIC <150lg/L (n = 37) in the first trimester compared with those with UIC 150-249 lg/L (n = 86) (median interquartile range: 48.0 [2.2] vs. 49.0 [4.0] cm, p = 0.01). Maternal UIC <150 lg/L was negatively associated with birth length of newborns (Exp (B) = 0.33 [CI = 0.1-0.9], p = 0.03). Conclusions: In a population whose median iodine intake is sufficient, extensive individual variation occurs. Such abnormalities are associated with increased GDM and HDP when UIC is ‡250 lg/L, and lower infant birth length when UIC is <150 lg/L.

Objective: Maternal hypothyroidism during pregnancy may lead to adverse outcomes. Recently published guidelines by the American Thyroid Association (ATA) do not advocate for universal screening but recommend a case-finding approach in high-risk pregnant women. The present study aims to evaluate the accuracy of this approach in identifying women with thyroid dysfunction during early pregnancy. Subjects and methods: This is a multiple-center, cross-sectional study. Three hundred and one pregnant women were enrolled. Anamnesis and a physical examination were performed to detect which women fulfilled the criteria to undergo laboratory screening of thyroid dysfunction, according to the ATA's 2017 guidelines. The Zulewski's validated clinical score was applied to assess signs and symptoms of hypothyroidism. Serum levels of thyrotropin (TSH), free thyroxine (FT4), anti-thyroperoxidase (TPO-Ab), and anti-thyroglobulin (Tg-Ab) antibodies were determined. Results: Two hundred and thirty one women (78%) were classified as high risk, and 65 (22%) were classified as low risk for thyroid dysfunction. Regarding the clinical score, 75 patients (31.2%) presented mild symptoms that were compatible with SCH, of which 22 (7.4%) had symptoms as the only risk factor for thyroid disease. 17 patients (5.7%) had SCH, of which 10 (58.8%) belonged to the high-risk group, and 7 (41.2%) belonged to the low-risk group. OH was found in 4 patients (1.4%): 3 (75%) in the high-risk group and 1 (25%) in the low-risk group. Conclusions: The ATA's proposed screening criteria were not accurate in the diagnosis of thyroid dysfunction in pregnancy. Testing only the high-risk pregnant women would miss approximately 40% of all hypothyroid patients. Arch

No abstract

Desenvolvido pelo Departamento de Tireoide da Sociedade Brasileira de Endocrinologia e Metabologia (SBEM), o Guia Prático em Doenças da Tireoide está integrado ao rol de materiais de divulgação científica e educação médica lançados pela instituição nos últimos anos. Em 28 capítulos elaborados por professores, pesquisadores e endocrinologistas com reconhecimento mundial e larga experiência clínica, o guia contempla tópicos que se estendem da fisiologia tireoidiana à abordagem diagnóstica e terapêutica dos pacientes com as mais diversas doenças da tireoide. A confiabilidade dos dados compilados e o sólido conhecimento de seus colaboradores condicionam este livro como auxílio essencial para consulta durante o atendimento dos pacientes em consultórios, ambulatórios ou enfermarias, além de oportunidade única de atualização a estudantes, médicos residentes e profissionais com particular interesse na Tireoidologia.

Background: Planar scintigraphy has long been indicated in patients receiving I-131 therapy for thyroid cancer to determine the anatomic location of metastases. We studied our experience upon implementing additional SPECT-CT scanning in these patients. Method: We performed a retrospective study of consecutive adult patients with newly diagnosed thyroid cancer treated with I-131 between 2011 and 2017. Radiologic findings detected with planar scintigraphy alone versus those identified with SPECT- CT scanning were primary endpoints. Result: 212 consecutive patients with thyroid cancer were analyzed in two separate cohorts (107 planar scintigraphy alone;105 planar scintigraphy with SPECT-CT). The addition of SPECT-CT resulted in more findings, both thyroid-related and incidental. However, we identified only 3 of 21 cases in which SPECT- CT provided unequivocal additional benefit by changing clinical management beyond planar scintigraphy alone. No difference in the detection of distant metastatic disease or outcome was identified between cohorts. Conclusion: Synergistic SPECT-CT imaging in addition to planar nuclear scintigraphy adds limited clinical value to thyroid cancer patients harboring low risk of distant metastases, while frequently identifying clinically insignificant findings. These data from a typical cohort of patients receiving standard thyroid cancer care provide insight into the routine use of SPECT-CT in such patients.