Dose-dependent incidence of agranulocytosis in patients treated with methimazole and propylthiouracil.

Agranulocytosis is a serious adverse effect of methimazole (MMI) and propylthiouracil (PTU), and although there have been reports suggesting a dose-dependent incidence in relation to both drugs, the evidence has not been conclusive. The objective of our study was to determine whether the incidences of agranulocytosis induced by MMI and PTU exhibit dose-dependency. The subjects were 27,784 patients with untreated Graves' disease, 22,993 of whom were on an antithyroid drug treatment regimen for more than 90 days. Within this subset, 18,259 patients had been treated with MMI, and 4,734 had been treated with PTU. The incidence of agranulocytosis according to dose in the MMI group was 0.13% at 10 mg/day, 0.20% at 15 mg/day, 0.32% at 20 mg/day, and 0.47% at 30 mg/day, revealing a significant dose-dependent increase. In the PTU group, there were 0 cases of agranulocytosis at doses of 125 mg/day and below, 0.33% at 150 mg/day, 0.31% at 200 mg/day, and 0.81% at 300 mg/day, also revealing a significant dose-dependent increase. The incidence of agranulocytosis at MMI 15 mg and PTU 300 mg, i.e., at the same potency in terms of hormone synthesis inhibition, was 0.20% and 0.81%, respectively, and significantly higher in the PTU group. Our findings confirm a dose-dependent increase in the incidence of agranulocytosis with both drugs, but that at comparable thyroid hormone synthesis inhibitory doses PTU has a considerably higher propensity to induce agranulocytosis than MMI does.

Clinical features of moyamoya disease with Graves' disease: a retrospective study of 394,422 patients with thyroid disease.

Graves' disease has been reported to affect the clinical features of moyamoya disease (MMD), an occlusion of the circle of Willis. This study aimed to clarify the characteristics of MMD in patients with Graves' disease. This was a single-center, retrospective study. The prevalence and clinical features of MMD patients among all patients with thyroid disease who visited Ito Hospital from January 2005 to December 2019 were evaluated. The relationship between MMD and hyperthyroidism was analyzed in new-onset Graves' disease patients during the same period. Of all 394,422 patients with thyroid disease, 88,180 had Graves' disease, and 40 had MMD with Graves' disease, i.e., the prevalence was 45.36 per 100,000 patients with Graves' disease (0.0454%). The median age at onset of MMD was 39 years (interquartile range, 31-54 years), with a male to female ratio of 1:12. The most common time that MMD was diagnosed was within 1 year after the onset of Graves' disease, in 9 of 40 patients (22.5%), and 19 of 40 patients (47.5%) underwent bypass surgery for MMD. In MMD with Graves' disease, headache was the most frequent symptom, and ischemic types of stroke and bilateral lesions were common. Of 23,347 patients with new-onset Graves' disease, 7 were diagnosed with MMD and the incidence of MMD was 5.94 patients per 100,000 person-years. Most patients developed MMD symptoms during hyperthyroidism. Although MMD is a rare condition, it should be noted that it can occur with Graves' disease.

Radioiodine uptake after monotherapy with potassium iodide in patients with Graves' disease.

The effect of potassium iodide (KI) on radioiodine uptake (RAIU) before radioisotope therapy in Graves' disease (GD) patients was investigated. A total of 82 patients who had been treated with KI monotherapy before 24-hour RAIU (24 h RAIU) were evaluated and 354 of those who had been treated with thiamazole (MMI) monotherapy were extracted from the 1,130 GD patients who were identified as having had appropriate iodine restriction based on urinary iodine excretion. Urinary iodine excretion (UIE) <200 µg/day was confirmed in all subjects. Propensity score-matching was performed to identify the difference in 24 h RAIU between the KI group and the MMI group. In addition, multiple regression analysis was performed to evaluate related to 24 h RAIU. Propensity score-matching resulted in 57 matched patients in each group. After matching, 24 h RAIU was still significantly lower in the KI group than in the MMI group (median 53% (interquartile range 47-61%) vs. 63% (56-66%); p = 0.001). In addition, KI monotherapy was weakly negatively correlated with 24 h RAIU, whereas the female sex and FT3 were very weakly positively correlated on multiple regression analysis. The results suggest that KI monotherapy likely suppressed 24 h RAIU more than MMI monotherapy in GD patients with appropriate iodine restriction, given the difference in the mechanism of hormone suppression.

Incidence and risk factors for Graves' orbitopathy in patients who underwent anti-inflammatory and immunosuppressive treatment during medical treatment for Graves' disease: investigation of 1,553 cases with newly diagnosed Graves' disease and proposal of a predictive score.

Appropriate administration of anti-inflammatory and immunosuppressive treatment (AIIST) is important for patients with Graves' orbitopathy (GO). This study aimed to clarify the incidence and risk factors for GO treated with AIIST and propose a predictive score, among newly diagnosed Graves' disease (GD) patients in Japan. A total of 1,553 GD patients who were newly diagnosed during the year 2011 were investigated. AIIST included local and/or systemic glucocorticoid administration and retrobulbar irradiation. A multivariable Cox proportional hazards model was used to investigate the risk factors for GO underwent AIIST during medical treatment, including at diagnosis, of GD. Then, a GO score was created by summing each point assigned to risk factors based on their coefficient obtained in the Cox model. AIIST was administered to 107 patients (6.9%). The risk factors and hazard ratios for GO underwent AIIST were: age (per 10 years), 1.32 (95% confidence interval: 1.16-1.50), p < 0.0001; TSH binding inhibitory immunoglobulin (TBII) (per 10 IU/L), 1.33 (1.15-1.54), p = 0.0001; and thyroglobulin antibody (TgAb) negativity, 2.98 (1.96-4.59), p < 0.0001. The GO score, ranging from 0 to 8 points, showed moderate performance (area under the curve: 0.71, cut-off value: 5 points, sensitivity: 0.76, specificity: 0.59, positive predictive value: 0.12, negative predictive value: 0.97). AIIST was performed for patients with active manifestations of GO in 6.9% of newly diagnosed GD patients. The risk factors for GO underwent AIIST were higher age, higher TBII, and TgAb negativity. The GO score based on these factors may be useful in managing GO.

Establishment of reference intervals for fT3, fT4, and TSH levels in Japanese children and adolescents.

The present study aimed to establish new reference intervals (RIs) for serum free triiodothyronine (fT3), free thyroxine (fT4), and thyroid stimulating hormone (TSH) levels in Japanese children and adolescents aged 4 to 19 years. A total of 2,036 (1,611 girls, 425 boys) participants were included over a 17-year period; they all tested negative for antithyroid antibodies (TgAb, TPOAb) and were found to have no abnormalities on ultrasonography. RIs were determined by nonparametric methods. The results showed that serum fT3 was significantly higher in the 4-15-year-olds than in the 19-year-olds. The serum fT4 was significantly higher in the 4-10-year-olds than in the 19-year-olds. The serum TSH was significantly higher in the 4-12-year-olds than in the 19-year-olds. All of them gradually decreased with age to approximate the adult levels. The upper limit of TSH was lower in those aged 13 to 19 years than in adults. The differences were examined by sex. The serum fT3 was significantly higher in boys than in girls between the ages of 11 and 19 years. The serum fT4 was significantly higher in boys than in girls between the ages of 16 and 19 years. There did not seem to be any sex difference in those under 10 years of age. In conclusion, serum fT3, fT4, and TSH levels in children and adolescents differ from those in adults. It is important to evaluate thyroid function using the new RIs that are appropriate for chronological age.

Prediction model of Graves' disease in general clinical practice based on complete blood count and biochemistry profile.

Although untreated Graves' disease (GD) is associated with a higher risk of cardiac complications and mortality, there is no well-established way to predict the onset of thyrotoxicosis in clinical practice. The aim of this study was to identify important variables that will make it possible to predict GD and thyrotoxicosis (GD + painless thyroiditis (PT)) by using a machine-learning-based model based on complete blood count and standard biochemistry profile data. We identified 19,335 newly diagnosed GD patients, 3,267 PT patients, and 4,159 subjects without any thyroid disease. We built a GD prediction model based on information obtained from subjects regarding sex, age, a complete blood count, and a standard biochemistry profile. We built the model in the training set and evaluated the performance of the model in the test set by using the artificial intelligence software Prediction One. Our machine learning-based model showed high discriminative ability to predict GD in the test set (area under the curve [AUC] 0.99). The main contributing factors to predict GD included age and serum creatinine, total cholesterol, alkaline phosphatase, and total protein levels. We still found high discriminative ability even when we restricted the variables to these five most contributory factors in our prediction model (AUC 0.97) built by using artificial intelligence software showed high GD prediction ability based on information regarding only five factors.

A case of macro-TSH consisting of IgA-bound TSH.

An asymptomatic, 68-year-old Japanese man visited our hospital for further examination of subclinical hypothyroidism. At the first visit, the serum TSH level was markedly elevated (36.6 µIU/mL), but the serum level of free T4 was within the reference interval. Thyroid dysfunction due to dietary iodine excess was initially suspected. However, even after iodine restriction, his thyroid function tests were the same as at the first visit, which suggested false elevation of the TSH level. The TSH levels were compared among three different measurement systems, which showed a similar tendency of TSH elevation above the reference interval, but the different TSH elevation levels among the measurement methods suggested the existence of some interfering substance. Neither serial dilution of the patient's serum nor polyethylene glycol and protein G precipitation tests showed any significant changes in the recovery rate. IgG-bound macro-TSH was ruled out. The TSH peak on gel filtration chromatography was located at a molecular size greater than IgA, which suggested the presence of IgA-bound TSH. After precipitation with Jacalin, which binds specifically to IgA, the TSH level decreased from 30.7 µIU/mL to 2.01 µIU/mL, within the reference interval. Thus, IgA-bound macro-TSH was identified. Macro-TSH is a rare condition in which an immunoglobulin-bound, high-molecular-weight form of TSH results in a false elevation of the serum TSH level. When there is a discrepancy between the results of thyroid function tests and clinical symptoms, and macro-TSH is suspected, it is necessary to know that not only IgG-bound TSH but also IgA-bound TSH could be the cause.

Propylthiouracil-induced otitis media with anti-neutrophil cytoplasmic antibody-associated vasculitis: a case report and review of the literature.

Propylthiouracil (PTU)-induced otitis media with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (OMAAV) is an extremely rare adverse event associated with anti-thyroid drugs and is not well recognized. A 42-year-old woman with Graves' disease undergoing PTU therapy for 8 years visited our hospital because of earache and congested feeling in her left ear. Blood tests, a computed tomography scan and pure tone audiometry revealed otitis media and moderate mixed hearing impairment. Antibiotics, ear drops with antibiotics and painkillers were administered. However, her earache and hearing loss gradually got worse and symptoms of facial nerve palsy appeared. At several weeks after initiation of the treatment, a high serum level of myeloperoxidase (MPO)-ANCA, 75.6 U/mL, was revealed. After excluding other causes, she was diagnosed with OMAAV. PTU was suspected as the cause of her OMAAV and was immediately discontinued, and prednisolone was started. Hearing impairment in her left ear gradually got better and showed substantial improvement. Facial nerve palsy disappeared. Although PTU-induced OMAAV is an extremely rare disease, it is important to recognize the disease, as delayed treatment can lead to irreversible hearing loss, hypertrophic pachymeningitis, and subarachnoid hemorrhage. When patients taking anti-thyroid drugs, especially PTU, are diagnosed with refractory otitis media or hearing loss, it is possible that OMAAV might be the cause and thus serum ANCA levels should be evaluated.

TRAb elevations occurred even in the third trimester; a case of a mother of a child with neonatal thyroid dysfunction, who received radioactive iodine therapy for Graves' disease.

Activity of Graves' disease (GD) is known to improve during gestation, as values of thyrotropin (TSH) receptor antibody (TRAb) also improve. However, the risk of neonatal hyperthyroidism increases when maternal TRAb values are high in the second to third trimester. A 29-year-old woman who had undergone radioactive iodine (RAI) therapy for GD 10 years earlier visited our hospital at 17 weeks of gestation, showing subclinical hypothyroidism and a positive TRAb value of 2.6 IU/L (reference range, <2.0 IU/L). Thyroid hormone replacement therapy was commenced and thyroid function normalized within 4 weeks, although TRAb was elevated at the time (3.8 IU/L). Prenatal check-up showed normal growth development and no irregularities. At 29 weeks of gestation, serum TRAb was extremely elevated, up to 16.8 IU/L. Since the risk of neonatal hyperthyroidism was of great concern, delivery was planned at an advanced-care medical center. At 38 weeks 5 days of gestation, she delivered a female neonate without any complications, although blood testing of the neonate showed subclinical hyperthyroidism with positive TRAb and TSH receptor stimulating antibody (TSAb). According to the American Thyroid Association guidelines, the TRAb value should be checked in the third trimester if mothers show a TRAb elevation between the initial visit after pregnancy and 18-22 weeks of gestation. However, if the mother has a history of RAI therapy for GD, regardless of thyroid function during gestation, the possibility of TRAb values elevating over time even years after the definitive therapy must be considered.

Therapeutic efficacy and limitations of potassium iodide for patients newly diagnosed with Graves' disease.

The efficacy of potassium iodide (KI) for Graves' disease (GD) has been reported, although few clinical reports have examined the long-term efficacy of treatment. The objective of this study was to investigate the efficacy and limitations of KI treatment for GD. This study enrolled patients newly diagnosed with mild GD, defined as free thyroxine (FT4) <5.0 ng/dL, between July 2014 and June 2016. KI was started at a dose of 50 mg/day, and if FT4 values did not decrease after initiation of treatment, doses were increased to 100 mg/day. Patients for whom thyroid hormone levels could not be controlled with KI at 100 mg/day were regarded as non-responders. Of the 122 patients (13 males, 109 females) included in this study, 71 (58.2%) responded to KI therapy. The remaining 51 patients (41.8%) were non-responders. The median duration required to judge non-responsiveness was 5.9 months. Multiple logistic regression analysis performed on parameters measured at the initial visit indicated FT4 (odds ratio (OR) 2.19, 95% confidence interval (CI) 1.28-3.75; p = 0.0007) and male sex (OR 3.58, 95%CI 1.04-12.3; p = 0.04) were significantly associated with KI responsiveness. Receiver operating characteristic (ROC) curve analysis of the relationship between FT4 and KI responsiveness indicated an FT4 cut-off of 2.76 ng/dL was optimal for differentiating between responders and non-responders. KI therapy was effective and safe for about 60% of patients with mild GD.

Levothyroxine supplementation improves serum anti-Müllerian hormone levels in infertile patients with Hashimoto's thyroiditis.

AIM: Thyroid dysfunction and autoimmunity are associated with an adverse effect on fertility. An aberrant high thyroid stimulating hormone level is associated with diminished ovarian reserve in women of reproductive age; however, the utility of levothyroxine (LT4) replacement for infertile patients with subclinical hypothyroidism is still under discussion. The aim of this study was to investigate whether LT4 supplementation for infertile patients with subclinical hypothyroidism improves impaired ovarian function. METHODS: We measured levels of serum thyroid-related hormones and a biomarker of ovarian function, anti-Müllerian hormone (AMH) in infertile women from 2014 to 2015. Out of a consecutive 1431 infertile patients, 311 patients with an elevated thyroid stimulating hormone level (≥ 2.5 µIU/mL) underwent detailed thyroid examinations, including blood tests of thyroid antibodies. We recruited 174 infertile patients, excluding patients with factors impacting ovarian and thyroid function. We evaluated alterations in AMH and thyroid related hormone levels during LT4 supplementation and infertility treatment with assisted reproductive technology. RESULTS: After LT4 supplementation, no significant change in the average AMH level was detected overall. However, the AMH level in 35 patients with Hashimoto's disease increased significantly after treatment (1 month 1.3 ± 0.5 fold, P = 0.007; 3 months 1.3 ± 0.4 fold, P = 0.040). The AMH level in patients with thyroglobulin antibody-positive and thyroid peroxidase antibody-negative also significantly increased after LT4 treatment (1 and 3 months 1.5 fold; P = 0.023). CONCLUSION: In the patients with Hashimoto's disease, preconception LT4 treatment may relieve adverse effects, including autoimmune antibodies, and support follicular development.

TSH receptor antibody titers measured with a third-generation assay did not reflect the activity of Graves' ophthalmopathy in untreated Japanese Graves' disease patients.

TSH receptor antibody (TRAb) titer has been reported to be correlated with Graves' ophthalmopathy (GO). However, the correlation between GO activity and TRAb titer assessed with a third-generation assay has not been reported. We enrolled 238 untreated Graves' disease patients who came to the outpatient clinic of Ito Hospital and 28 patients who were euthyroid. All of the patients were assessed for GO by an ophthalmologist within 3 months of their initial visit to Ito Hospital. Clinical activity score (CAS), short inversion time inversion recovery (STIR), and sum of the maximum external orbital muscle areas (SEOMA) on a frontal sectional magnetic resonance imaging (MRI). The TRAb titer was significantly higher in patients with inactive ophthalmopathy (the inactive-GO group) than in patients with active ophthalmopathy (the active-GO group) (17.7 ± 13.5 IU/L vs. 13.0 ± 13.1 IU/L, p=0.0082). The SEOMA values were not correlated with TRAb titer. The prevalence of active-GO was higher in euthyroid patients than in hyperthyroid patients although the difference was not significant. In conclusion, TRAb titer measured with a third-generation assay dose not correlate with GO activity based on MRI findings in untreated Graves' disease patients, and the prevalence of active-GO is higher in euthyroid patients with lower TRAb titers than in hyperthyroid patients.

The characteristics of osteoporotic patients in Graves' disease patients newly diagnosed after menopause: a prospective observational study.

Overt hyperthyroidism is associated with reduced bone density. The extent of restoration of reduced bone density caused by hyperthyroidism in postmenopausal Graves' disease (GD) patients has not fully been investigated. We examined 85 newly diagnosed postmenopausal GD patients, and we measured their serum thyroid hormone levels as well as their bone turnover marker levels and the bone mineral density (BMD) of their lumbar spine (LS), both femoral necks (FN), and left distal radius (DR). We prospectively observed the patients for changes in BMD and bone turnover marker levels during a 24-month period after euthyroidism had been established by ATD treatment. The median age of the subjects was 57 years old (range: 50 to 79). 46 (54.1%) patients had osteoporosis. 42 of the 46 osteoporosis patients had low BMD in the DR. The patients with osteoporosis were significantly older, had a significantly lower BMI, and had significantly higher bone turnover marker levels compared to the normal BMD patients. The best predictor of the BMD in the DR was BMD in the FN (ß = 0.40, p < 0.0001). A total of 42 patients were followed up for 24 months after attainment of euthyroidism, and 19 of them were osteoporosis at the first visit. The BMD of the 19 osteoporotic patients had increased by 4.9% in the LS, 11.9% in the FN, and 9.3% in the DR at 24 months. After maintaining a euthyroid state for 24 months by means of ATD treatment, 26% of the osteoporotic patients had recovered from osteoporosis.

Serum human chorionic gonadotropin levels and thyroid hormone levels in gestational transient thyrotoxicosis: Is the serum hCG level useful for differentiating between active Graves' disease and GTT?

Gestational transient thyrotoxicosis (GTT) is defined as transient thyrotoxicosis caused by the stimulating effect of human chorionic gonadotropin (hCG) during pregnancy. We attempted to identify the serum hCG level that causes GTT, and we compared the serum hCG levels and thyroid hormone levels of GTT patients according to whether they had a background of thyroid disease. We also evaluated serum hCG as a parameter for differentiating between active Graves' disease (GD) and GTT. We reviewed the 135 cases of pregnant women who came to our hospital to be evaluated for thyrotoxicosis during their 7th to 14th week of pregnancy, and their serum hCG level was measured at that time. Among the 135 pregnant women with thyrotoxicosis; 103 of the women had GTT, and the other 32 women had active GD. There were no correlations between their serum hCG levels and free thyroid hormone levels. There were no significant differences in thyroid hormone levels or hCG levels among the GTT groups with different thyroid disease backgrounds; i.e., the GTT group without thyroid disease, GTT group with chronic thyroiditis, GTT group with non-functioning thyroid nodules, and GTT group with GD in remission. The serum hCG level of the GTT group was significantly higher than in the active GD group, but it was not a good parameter for differentiating between the two groups. The FT3/FT4 ratio of the active GD was significantly higher than in GTT group, and was a better parameter for differentiation.

Changes in pediatric thyroid sonograms in or nearby the Kanto region before and after the accident at the Fukushima Daiichi nuclear power plant.

Following the accident at the Fukushima Daiichi Nuclear Power Station which occurred on March 11, 2011 due to the Eastern Japan Great Earthquake (the Accident), there have been concerns over elevation of the risk of thyroid cancer among children due to internal exposure to radioactive iodine. In Fukushima Prefecture, screening of children with thyroid ultrasonography has been carried out, yielding numerous findings, suggesting a possible influence from the Accident. We report thyroid ultrasonographic findings, used by similar device at Fukushima Prefecture's study, at Ito-hospital. Of the 2721 children aged 15 or less who visited our hospital between January 2005 and March 2013, 1214 children (330 boys and 884 girls; median age, 12; range of age, 4-15) were covered by evaluation of thyroid ultrasonographic findings, excluding children known in advance to have thyroid disease on the basis of disease history, palpation and blood tests. Among these 1214 children, 709 children (58.4%) were found cysts (≤ 5 mm in 665 cases) by ultrasonography, 43 children (3.5%) were found nodules (≤ 5 mm in 18 cases) and 9 children (5.2%) were found an intrathyroid ectopic thymus. Analysis of the data before and after the Accident using the same device, involving age adjustment on the basis of the standard population in 2010, showed no difference in the incidence rate of cysts or nodules. In children examined, the incidence rate of cyst formation (particularly ≤ 5 mm) was higher, and there was no difference in the incidence rate of cysts or nodules between the pre- and post-accident period.

Effects of Levothyroxine Treatment on Fertility and Pregnancy Outcomes in Subclinical Hypothyroidism: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Background: Subclinical hypothyroidism, defined by elevated thyrotropin (TSH) and normal free thyroxine levels, is associated with adverse pregnancy outcomes, including preterm birth, pre-eclampsia, and small for gestational age. Despite the uncertainty regarding the effectiveness of levothyroxine (LT4) treatment on pregnancy outcomes in subclinical hypothyroidism, LT4 is widely administered with a pre-treatment threshold TSH level of 2.5 mU/L. The aim of this study is to investigate the efficacy of periconceptional LT4 treatment for subclinical hypothyroidism, including TSH levels >2.5 mU/L, and identify the characteristics of subclinical hypothyroidism that can benefit from LT4 treatment. Methods: We conducted a systematic review and meta-analysis of randomized controlled trials from inception to February 2023. We analyzed the pooled effects of LT4 on subclinical hypothyroidism before and during pregnancy. The main outcomes before pregnancy were live birth, pregnancy, and miscarriage. The main outcomes during pregnancy were live birth, miscarriage, and preterm birth. We conducted subgroup analyses to compare the effects of LT4 on subclinical hypothyroidism with TSH levels of 2.5-4.0 and >4.0 mU/L. Results: Of the 888 studies identified, 27 full-text articles were screened for eligibility. Five studies on pre-conception treatment with 768 participants and eight studies on treatment during early pregnancy with 2622 participants were analyzed. One of the two studies on pre-conception treatment in subclinical hypothyroidism with TSH >4.0 mU/L had high risk of bias and the other was composed of 64 participants. Pre-conception LT4 treatment had no significant effect in improving rates of live births and pregnancies, or reducing miscarriages (risk ratio [RR], 95% confidence interval): 1.41 (0.84-2.36), 1.73 (0.88-3.39), and 0.46 (0.11-2.00), respectively. LT4 treatment during pregnancy was not significantly associated with higher rates of live births (RR 1.03, 0.98-1.09) nor decreased miscarriage rates (RR 1.01, 0.66-1.53). The effect of LT4 treatment on preterm birth during pregnancy was significantly different depending on the TSH values (p = 0.04); a positive effect was shown in the subclinical hypothyroidism subgroup with TSH >4.0 mU/L (RR 0.47, 0.20-1.10), while no significant effect was observed in the subgroup with TSH 2.5-4.0 mU/L (RR 1.35, 0.79-2.31). Conclusions: Pre-conceptional LT4 treatment for subclinical hypothyroidism does not improve fertility or decrease the incidence of miscarriages. However, further well-designed studies are needed for pre-conceptional treatment, especially in TSH >4.0 mU/L. LT4 treatment during pregnancy had a positive effect on preterm birth; nevertheless, this was only applicable to subclinical hypothyroidism with TSH >4.0 mU/L.

An Evaluation of the Efficacy of Machine Learning in Predicting Thyrotoxicosis and Hypothyroidism: A Comparative Assessment of Biochemical Test Parameters Used in Different Health Checkups.

Objective This study assessed the efficacy of machine learning in predicting thyrotoxicosis and hypothyroidism [thyroid-stimulating hormone >10.0 mIU/L] by leveraging age and sex as variables and integrating biochemical test parameters used by the Japan Society of Health Evaluation and Promotion (JHEP) and the Japan Society of Ningen Dock (JND). Methods Our study included 20,653 untreated patients with Graves' disease, 3,435 untreated patients with painless thyroiditis, 4,266 healthy individuals, and 18,937 untreated patients with Hashimoto's thyroiditis. Machine learning was conducted using Prediction One on three distinct datasets: the Ito dataset (age, sex, and 30 blood tests and biochemical test data), the JHEP dataset (age, sex, and total protein,total bilirubin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyl transpeptidase (γGTP), alkaline phosphatase, creatinine (CRE), uric acid (UA), and T-Cho test data), and the JND dataset (age, sex, and AST, ALT, γGTP, CRE, and UA test data). Results The results for distinguishing thyrotoxicosis patients from the healthy control group showed that the JHEP dataset yielded substantial discriminative capacity with an area under the curve (AUC) of 0.966, sensitivity of 92.2%, specificity of 89.1%, and accuracy of 91.7%. The JND dataset displayed similar robustness, with an AUC of 0.948, sensitivity of 92.0%, specificity of 81.3%, and accuracy of 90.4%. Differentiating hypothyroid patients from the healthy control group yielded similarly robust performances, with the JHEP dataset yielding AUC, sensitivity, specificity, and accuracy values of 0.864, 84.2%, 72.1%, and 77.4%, respectively, and the JND dataset yielding values of 0.840, 83.2%, 67.2%, and 74.3%, respectively. Conclusion Machine learning is a potent screening tool for thyrotoxicosis and hypothyroidism.

Determination of pediatric reference levels of FT3, FT4 and TSH measured with ECLusys kits.

Reference ranges for serum thyroid hormones free triiodothyronine (FT3), free thyroxine (FT4) and thyroid stimulating hormone (TSH) in children were set using the assay kits currently used in clinical settings. A total of 342 children (111 males and 231 females) who were negative for antithyroid antibodies (TgAb, TPOAb) and were found to have no abnormalities on ultrasonographic examination of the thyroid gland were divided into 6 age groups: 4-6 years (45 children), 7-8 years (40), 9-10 years (53), 11-12 years (65), 13-14 years (83), and 15 years (56) for the study. FT3, FT4 and TSH levels were determined by electrochemiluminescence immunoassay (ECLIA) (ECLusys FT3, FT4 and TSH).The reference range for FT3 (pg/mL) was 2.91-4.70 for the age group of 4-6 years, 3.10-5.10 for the age group of 7-8 years, 3.10-4.87 for the age group of 9-10 years, 2.78-4.90 for the age group of 11-12 years, 2.77-4.59 for the age group of 13-14 years, and 2.50-4.64 for the age group of 15 years . The reference range for FT4 (ng/dL) was 1.12-1.67, 1.07-1.61, 0.96-1.60, 1.02-1.52, 0.96-1.52, 0.95-1.53. The reference range for TSH (µU/mL) was 0.62-4.90, 0.53-5.16, 0.67-4.52, 0.62-3.36, 0.54-2.78, 0.32-3.00. Serum FT3, FT4 and TSH levels in children differ from those in adults. It is, therefore, of importance to perform evaluation of thyroid function in children using reference values appropriate for the chronological ages, because misdiagnosis of hypothyroidism or inappropriate secretion of TSH (SITSH) and oversight of mild subclinical hypothyroidism could occur if the diagnosis is made using reference values for adults.

Incidence of and Risk Factors for Neonatal Hypothyroidism Among Women with Graves' Disease Treated with Antithyroid Drugs Until Delivery.

Background: The incidence of neonatal hypothyroidism among newborns born to mothers with Graves' disease (GD) who continued antithyroid drug (ATD) treatment until delivery has never been reported. Objective: Our primary objective was to investigate the incidence of neonatal hypothyroidism among newborns born to mothers with GD who were treated with ATD until delivery. Our secondary objective was to identify the cutoff ATD daily doses for neonatal hypothyroidism risk, based on maternal thyrotropin (TSH) receptor antibody (TRAb) levels. Methods: We conducted a retrospective cohort study. We included 305 pregnant women with GD who were treated with an ATD until delivery (63 treated with methimazole [MMI] and 242 treated with propylthiouracil [PTU]). Umbilical cord TSH, free thyroxine (fT4), and TRAb levels were measured at delivery, and we investigated the respective relationships between neonatal hypothyroidism at delivery and maternal fT4 levels, TRAb levels, and daily ATD doses during pregnancy. Neonatal hypothyroidism was diagnosed when the umbilical cord fT4 level was below the lower limit of the reference range. Results: The incidence of neonatal hypothyroidism at delivery was 19.0% ([confidence interval, CI, 11.2-30.4]; 12/63) in the MMI group and 12.8% ([CI, 9.2-17.6]; 31/242) in the PTU group. Neonatal goiter was observed in one neonate in the PTU group, and two infants in the PTU group required levothyroxine treatment. The daily ATD dose in the third trimester was the strongest predictor of neonatal hypothyroidism at delivery; the cutoff MMI dose was 10 mg/day, and the cutoff PTU dose was 150 mg/day. When the maternal TRAb level in the third trimester was above three times the upper limit of the normal range, the cutoff MMI dose was 20 mg/day, and the cutoff PTU dose was 150 mg/day. Conclusions: Maternal fT4 and TRAb levels were higher in the neonatal hypothyroid group, which suggested prolonged GD activity. Careful follow-up is necessary when maternal GD remains active and the ATD dose to control maternal thyrotoxicosis cannot be reduced.

Adult Thyroid Outcomes of Congenital Hypothyroidism.

Background: More than 40 years have passed since the introduction of newborn screening (NBS) for congenital hypothyroidism (CH), and many early diagnosed patients have reached adulthood. Their thyroid morphology and function have been little studied. This cross-sectional, observational study was conducted to characterize the thyroid morphology and function of adult CH patients diagnosed in the framework of NBS for CH. Methods: A total of 103 adult CH patients born after 1979 were enrolled at Ito Hospital, Tokyo, Japan, and were classified into Goiter, Normal gland, and Dysgenesis groups based on ultrasonographic findings. For 60 patients, genetic analysis was performed. Thyroid function test results and the proportion of patients with thyroid nodules were compared among the three groups and between 56 female CH patients and 168 non-CH women matched for thyrotropin levels. Results: A significantly low serum free triiodothyronine/free thyroxine ratio (0.22) was observed in the Dysgenesis group. Thyroid nodules were detected in 14.3% (8/56) of female CH patients, more frequently than in non-CH women. Thyroid nodules were detected most frequently in the Goiter group (71%, 10/14). Genetic defects were identified in 89% (8/9) of patients belonging to the Goiter group, including thyroglobulin defect (33%, 3/9), thyroid peroxidase defect (33%, 3/9), and dual oxidase 2 defect (22%, 2/9). Conclusions: Our results suggest that adults with thyroid dysgenesis on levothyroxine replacement therapy have relative triiodothyronine deficiency. Most adults with goitrous CH have genetic dyshormonogenesis. They are at high risk of developing thyroid nodules. Our findings support the current guideline recommendation that CH patients with dyshormonogenesis should undergo periodic thyroid ultrasonography.