Hashimoto's thyroiditis: relative recurrence risk ratio and implications for screening of first-degree relatives

Thyroid ultrasonic changes relate to implantation failure in euthyroid women with thyroid autoimmunity undergoing in vitro fertilization/intracytoplasmic sperm injection

OBJECTIVE

To determine whether ultrasonic manifestations of Hashimoto's thyroiditis (HT) related to embryo qualities or pregnancy outcomes in women with thyroid autoimmunity (TAI) undergoing in vitro fertilization/intracytoplasmic sperm injection.

METHODS

Our study was a retrospective cohort study. A total of 589 euthyroid women enrolled from January 2017 to December 2019. 214 TAI women and 375 control women were allocated in each group according to serum levels of thyroid peroxidase antibodies (TPOAb) and/or anti-thyroglobulin antibodies (TgAb). Basal serum hormone levels and thyroid ultrasound were assessed, embryo qualities, pregnancy outcomes were collected from medical records. Diagnosis of thyroid ultrasound was used for subanalysis. Logistic regression was used to evaluate outcomes of embryo development and pregnancy.

RESULTS

Implantation rate was significantly lower in euthyroid women with TAI compared with control group (TAI group: 65.5% vs. Control group: 73.0%, adjusted OR (95% CI): 0.65 (0.44, 0.97), p = 0.04). We further stratified TAI group into two groups: one group with HT features under ultrasound and another group with normal thyroid ultrasound. After regression analysis, TAI women with HT morphological changes had a lower chance of implantation compared with control group (TAI group with HT: 64.1% vs. Control group: 73.0%, adjusted OR (95% CI): 0.63 (0.41, 0.99), p = 0.04), while there was no significant difference on implantation rate between TAI women with normal thyroid ultrasound and control group. Other outcomes, such as embryo qualities and pregnancy rate, were comparable between TAI and control groups.

CONCLUSIONS

A higher risk of implantation failure was seen among euthyroid women with TAI, especially women with HT morphological changes under ultrasound. The underlying mechanisms of implantation failure among euthyroid HT patients need further research.

Recurrence risk of autoimmune thyroid and endocrine diseases

BACKGROUND AND OBJECTIVE

The recurrence risk ratio (λ) expresses the risk ratio of index patients' first-degree relatives developing a disease as compared to the general population and is a quantitative measure of the genetic contribution to the disease. This paper offers the results of a specialized center as well as a review of the pertinent literature.

METHODS

Data from 3315 consecutive subjects followed at an ORPHAN academic tertiary referral expert center for endocrine autoimmunity as well as 419 unrelated German families were collected. λ was assessed based on 806 well-documented subjects, 299 index patients with autoimmune glandular (AIGD) and non-endocrine diseases and 507 of their first-degree relatives (328 children, 179 siblings).

RESULTS

As many as 36% of relatives of patients with autoimmune diseases (AID) were affected by various autoimmune conditions. Twenty-five percent and 23% of all relatives had an AIGD or an autoimmune thyroid disease (AITD), respectively. Furthermore, 29% and 25% of relatives of index cases with polyglandular (PGA) and monoglandular (MGA) autoimmunity were affected. The recurrence risk for AITD was increased 16-fold in both children and siblings compared to the general population (λ, 95% CI 16, 11-21 and 16, 12-19, respectively). Furthermore, λ for AITD/AIGD was 21.62 (95% CI 14.17-30.69)/17.57 (11.80-24.36) and 13.48 (8.42-20.52)/10.68 (6.76-16.02) for siblings of patients with PGA and MGA, respectively. Overall, a strong genetic component for AITD and AIGD with a significant genetic impact on the development of PGA was demonstrated.

CONCLUSION

These novel results strongly recommend the screening for AITD and AIGD in children and siblings of index patients with AITD.

Treatment of hypothyroidism in infants, children and adolescents

In 2014, treatment guidelines from the American Thyroid Association reflected the general consensus that levothyroxine (LT4), adjusted to maintain a normal thyrotropin (TSH) level, is the preferred method for treatment of hypothyroidism. Although this is generally applicable to children, there are subsets of children for whom the diagnosis and treatment of hypothyroidism are problematic. These include children with congenital hypothyroidism (CH), low birth weight (LBW) and very low birth weight (VLBW), Down syndrome (DS), subclinical hypothyroidism, and obesity. In this Review, we focus on the progress and remaining pitfalls in diagnosis and treatment of hypothyroidism in these and other groups.

Anti-thyroid antibodies in the relation to TSH levels and family history of thyroid diseases in young Caucasian women

BACKGROUND

In young women, hypothyroidism is associated with impaired fertility, increased risk of pregnancy loss, premature delivery, and impaired infant neurodevelopment, justifying the need to recognize the risk of hypothyroidism in women of reproductive age. Thus, this study aimed at assessing the frequency of occurrence of antibodies against thyroid peroxidase (TPOAb) and thyroglobulin (TGAb) in young Caucasian women in connection with various confounders.

METHODS

The cross-sectional study involved 366 women aged 18-40 years without a diagnosis of thyroid disease. The personal and family medical history was collected, body mass and height were measured and an ultrasound examination of the thyroid gland was performed. Thyrotropin (TSH), free thyroxine, and free triiodothyronine levels, as well as TPOAb and TGAb titers, were determined by ECLIA.

RESULTS

Two cases of hyperthyroidism (0.5%) and 6 cases (1.6%) of subclinical hypothyroidism were detected. TPOAb was detected in 21 (5.7%) and TGAb in 31 (8.6%) and any of the antibodies in 42 (11.6%) women. Antibodies were more frequent in the subgroup with TSH levels ≥ 2.5 mIU/L than in the subgroup with lower TSH levels (15.5% vs 6.9%, respectively, p<0.05). Any anti-thyroid antibodies were also detected more frequently in the subgroup with TSH levels ≥ 2.5 mIU/L (18.3% vs 10.0%, respectively, p<0.05). Women with the presence of TGAb or seropositive for either TGAb or TPOAb or TPOAb and TGAb antibodies were more likely to have higher TSH levels (OR = 2.48 and OR = 2.02; respectively, p < 0.05 for both). A family history of any thyroid diseases increased the risk of any anti-thyroid antibodies positivity (OR = 1.94; p < 0.05).

CONCLUSIONS

The results of our study suggest that TSH ≥ 2.5 mIU/L and a family history of any thyroid diseases justify screening for anti-thyroid antibodies in women of reproductive age, although the occurrence of these antibodies in the majority of cases is not related to thyroid dysfunction.

Clinical Characteristics and Follow-Up of 19 Children With Hashimoto's Thyroiditis Aged Below 3 Years: A Single-Center Retrospective Analysis

AIM

To analyze the clinical characteristics of Hashimoto's thyroiditis (HT) in children below 3 years of age in order to improve the understanding of the disease, avoid misdiagnosis, and achieve early diagnosis and treatment.

METHODS

The study retrospectively analyzed the clinical data of 19 patients diagnosed with HT in the first three years of life.

RESULTS

The patients (12 female, 7 male) had an average age of 26.1 ± 8.2 months (range 10-36 months). At presentation, one patient had euthyroidism, ten had hypothyroidism, seven had subclinical hypothyroidism, and one had hyperthyroidism. The most common reasons for doctor's visits were thyroid enlargement (21.1%), global developmental delay (21.1%), and routine thyroid function tests in patients with type 1 diabetes (26.3%). Sixteen patients provided follow-up data, and the mean follow-up time was 23.31 ± 16.44 months (range 1-48 months). In the hypothyroidism group, one patient stopped levothyroxine (LT4) treatment after 2 months; the remaining patients had been treated with LT4 since their diagnosis. In the subclinical hypothyroidism group, one patient whose thyroid function returned to normal after 1 month of being diagnosed was not treated. The remaining patients received LT4 treatment at their diagnosis or during follow-up. The patient with hyperthyroidism was treated with methimazole after diagnosis, but treatment was discontinued 11 months later and LT4 was initiated 26 months after diagnosis. One in four patients with global developmental delay approached normal mental development after LT4 treatment. Four in six patients with short stature achieved height catch-up.

CONCLUSION

At their initial HT diagnosis, most of the children showed hypothyroidism or subclinical hypothyroidism. Children with global developmental delay require continual screening, even if the thyroid function is normal after birth, to determine whether they have HT-induced hypothyroidism. Thyroxine replacement could partially relieve the clinical manifestations of hypothyroidism and early diagnosis and treatment are essential for improving patient prognosis.

Study of thyroid function in pregnancy, its feto-maternal outcome; a prospective observational study

Background

Pregnancy is a stress test of maternal thyroid function. The prevalence of thyroid dysfunction in pregnant women is high. Subclinical hypothyroidism occurs in 10% of all pregnancies. Effects of hypothyroidism in pregnancy are anemia, low birth weight and mental retardation in neonate. This study is aimed to evaluate maternal and fetal outcomes in pregnant women with deranged thyroid profile. The relevance of this study is to document the association of hypothyroidism and its adverse effects on mother and fetus.

Methods

This prospective observational study was carried out at R.D. Gardi Medical College, Ujjain, India. Subjects of this study were 198 antenatal women in third trimester with singleton pregnancy admitted in the obstetric ward, and informed consent was obtained. Women were chosen irrespective of age, parity, residence and socioeconomic status. Women with multiple pregnancy, a known case of thyroid disorder, or any pre-existing medical disorder were excluded. Routine hematological parameters and estimation of T3, T4 and TSH was conducted. Patients with deranged thyroid profile were subsequently assessed for maternal and fetal complications. History of infertility, family history of thyroid disease, menstrual pattern, recurrent abortion, hemoglobin level and fetal outcome were the main study variables. Data was analysed in SPSS software for statistical co-relation.

Results

Prevalence of thyroid disorder is 11%; with subclinical hypothyroidism, overt hypothyroidism and subclinical hyperthyroidism occurring in 5.6, 3.5 and 1.5% of subjects respectively. In women with subclinical and overt hypothyroidism, anemia was present in 26.3% being significantly associated with hypothyroidism (p = 0.008). With respect to fetal outcome, LBW 31.6% (p = 0.001), NICU admission 42.1%, (p = 0.000) and low APGAR Score (21.1%, p = 0.042) were statistically associated with hypothyroidism. Risk of anemia, Low Birth weight, NICU admissions, and low APGAR score was 4.8, 6.3, 0.14 and 3.64 times higher respectively in women with hypothyroidism than in women who are euthyroid.

Conclusion

Prevalence of subclinical hypothyroidism is 5.6% in 3rd trimester of pregnancy. Anemia, pre-eclampsia, high caesarean rates and neonatal morbidities is significantly associated with hypothyroidism.

THE ASSOCIATION OF SUBCLINICAL INSULIN RESISTANCE WITH THYROID AUTOIMMUNITY IN EUTHYROID INDIVIDUALS

Hashimoto thyroiditis is characterized by anti-thyroid peroxidase (anti-TPO) and anti-thyroglobulin (anti-Tg) antibodies that gradually lead to thyroid cell destruction. As hypothyroidism has been associated with insulin resistance (IR), we aimed to investigate whether IR is associated with thyroid antibody presence and whether the degree of IR correlates with their concentration in euthyroid individuals. A total of 164 non-diabetic, euthyroid individuals, average age 34 years, were included in the study, divided into two groups according to Hashimoto thyroiditis and underwent 5-hour oral glucose tolerance test. The degree of IR was evaluated by the Homeostatic Model Assessment of Insulin Resistance (HOMA-IR). The Hashimoto thyroiditis group had higher HOMA-IR (p=0.003) and lower glucose levels (p=0.04). HOMA-IR correlated positively with anti-TPO (p<0.001). Linear logistic regression revealed that anti-TPO concentration increased by 18.13 (p=0.001) with each HOMA-IR unit. IR might trigger thyroid antibody production and Hashimoto thyroiditis development, which needs to be evaluated in further larger scale follow up studies.

The characteristics and risk factors of central compartment lymph node metastasis in cN0 papillary thyroid carcinoma coexistent with Hashimoto's thyroiditis

Background

Currently, there are few studies on the characteristics of lymph node metastasis in the central region in patients with preoperative negative lymph node (cN0) papillary thyroid carcinoma (PTC) coexistent with Hashimoto's thyroiditis (HT). There is still a significant controversy on whether to perform prophylactic central compartment lymph node dissection for T1/T2 cN0 PTC. Therefore, we aimed to investigate the characteristics and risk factors of central compartment lymph node metastasis in cN0 PTC (T1 or T2 stage) coexists with HT.

Methods

From Jun. 2015 to Apr. 2019, the clinicopathological data of 354 patients with stage T1/T2 cN0 PTC admitted to the thyroid tumor surgery of Inner Mongolia People's Hospital were analyzed retrospectively. All patients underwent central compartment lymph node dissection. According to the results of the postoperative pathological examination, the patients were divided into two groups: PTC group (n=236) and PTC coexistent with the HT group (n=118).

Results

The proportion of PTC patients with HT was 33.33% (118/354) in T1/T2 cN0 PTC patients; most of them were women. The levels of serum thyrotropin, antithyroglobulin antibody, and thyroid peroxidase antibody in PTC coexistent with HT group are higher than those in the PTC group (P<0.05). The number of lymphadenectomies in PTC coexistent with HT group was more than that in PTC alone group (P<0.05). Univariate analysis showed that antithyroglobulin antibody positive, tumor diameter >1 cm, and multifocal cancer in T1/T2 stage cN0 PTC coexistent with HT group were all correlated with lymph node metastasis in the central region (P<0.05). Logistic regression analysis showed that tumor diameter >1 cm, and multifocal cancer were the risk factors of central compartment lymph node metastasis in patients with T1/T2 stage cN0 PTC coexistent with HT (P<0.05).

Conclusions

HT is not a relevant factor of central lymph node metastasis in T1/T2 cN0 PTC; regardless of the presence or absence of HT, tumor diameter >1 cm and multifocal cancer are risk factors for central lymph node metastasis in patients with T1/T2 cN0 PTC. Therefore, preventive lymph node dissection in the central region should be conducted actively during the operation.