Tireoidite de Hashimoto na Infância e na Adolescência: Estudo Retrospectivo de 43 Casos

Thyroid function and autoimmunity in children and adolescents with Type 1 Diabetes Mellitus

We evaluated 233 children and adolescents with T1 Diabetes to analyze the prevalence and characteristics of Autoimmune Thyroid Disease. AITD was found in 23%, the majority being female and patients older than 5 years of age. Screening is mandatory, and the best approach could be guided by gender and age.

TSH neurosecretory dysfunction (TSH-nd) in Down syndrome (DS): low risk of progression to Hashimoto's thyroiditis

INTRODUCTION

Patients with Down syndrome (DS) often have elevated TSH (hypothalamic origin), which is called TSH neurosecretory dysfunction (TSH-nd). In these cases, there is slight elevation in TSH (5-15 µUI/mL), with normal free T4 and negative thyroid antibodies (AB).

OBJECTIVE

To recognize the risk of progression to Hashimoto's thyroiditis (HT).

SUBJECTS AND METHODS

We retrospectively analyzed 40 DS patients (mean age = 4.5 years), followed up for 6.8 years.

RESULTS

HT was diagnosed in 9/40 patients, three early in monitoring, and six during evolution. In 31/40 patients, TSH-nd diagnosis remained unchanged over the years, with maximum TSH values ranging from 5 to 15 µUI/mL. In this group, free T4 also remained normal and AB were negative. There was a significant TSH reduction (p = 0.017), and normal TSH concentrations (< 5.0 µUI/mL) were observed in 29/31 patients, in at least one moment. No patient had TSH > 15 µUI/mL.

CONCLUSION

DS patients with TSH-nd present low risk of progression to HT (10% for females and 6% for males).

Excessive iodine intake and ultrasonographic thyroid abnormalities in schoolchildren

High nutritional levels of iodine may induce a higher prevalence of autoimmune thyroiditis, hypothyroidism, goiter, as well as hyperthyroidism, mostly in the elderly. This study assessed thyroid volume and ultrasonographic abnormalities as well as urinary iodine excretion (UIE) in 964 schoolchildren living in an iodine-sufficient area in southern Brazil. Thyroid volume correlated with age and body surface area in boys and girls. In 76.8% of the children, UIE was above 300 microg/l, with higher levels among boys compared to girls (484.2 microg/l vs 435.3 microg/l, p < 0.001). Thyroid abnormalities detected by ultrasonography included hemiagenesis (0.5%), nodules (0.2%), cysts (0.7%), and hypoechogenicity (11.7%). Goiter was present in 1.9% of the children. Hypoechogenicity, a relevant marker of autoimmune thyroiditis, was the most common abnormality found in our study, and this may be linked to excessive iodine intake.

[Evidences for subclinic chronic autoimmune thyroid disease in girls with Turner Syndrome]

Patients with Turner syndrome (TS) frequently exhibit transient, recurrent and asymptomatic variations of TSH and/or thyroid hormones (TH). This work was carried out to evaluate thyroid function and structure in patients with TS who had had such variations in hormone concentrations. Our sample comprised 24 patients, 17 less than 20-years old. Evaluation included serum levels of TSH, free T4, total T3, TPO and Tg autoantibodies, thyroid ultrasound (US) and scintigraphy with 99mTc-pertechnetate. Thirteen patients had abnormal TSH and/or TH levels; 23 exhibited US features compatible with chronic thyroid disorder, particularly thyromegaly (established according to volume expected for stature) and heterogeneous echogenicity. Uptake was normal in 21 cases and tracer distribution was homogeneous in 22. The finding of abnormal hormone concentrations was independent of age, length of time since the first similar finding, thyroid autoantibodies, number of abnormalities at US and abnormal scintigraphic findings. Patients aged more than 20 years had higher frequency of thyroid antibodies and heterogeneous echogenicity, and thyroid volume was significantly correlated to length of time since detection of the first hormone variation, indicating progressive thyroid disease. These results suggest that subclinical thyroid dysfunction in TS is due to chronic autoimmune thyroid disease.