Adult Thyroid Outcomes of Congenital Hypothyroidism

BACKGROUND

More than 40 years have passed since the introduction of newborn screening 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 newborn screening 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 TSH levels.

RESULTS

A significantly low serum free T3/free T4 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 the 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 T3 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.

Cardiac Troponin Is Elevated in Patients with Thyrotoxicosis and Decreases as Thyroid Function Improves and Brain Natriuretic Peptide Levels Decrease

INTRODUCTION

High-sensitive cardiac troponin reflects micro-myocardial injury in the absence of overt myocardial infarction.

OBJECTIVE

This study aimed to clarify how thyrotoxicosis affects cardiac troponin.

METHODS

This was a prospective observational study in Japan. Untreated patients with thyrotoxicosis who visited Ito Hospital were enrolled, and medical treatment was initiated for hyperthyroidism. Thyroid function, high-sensitive troponin I (hsTnI), and brain natriuretic peptide (BNP) were measured at baseline and then every 3 months for 1 year.

RESULTS

Data from a total of 143 patients (median age, 42 years; 32 men and 111 women) were investigated. At baseline, median hsTnI was 1.9 pg/mL and ranged from 0 to 69.6 pg/mL. Five patients (3.5%) had a high hsTnI value that exceeded 26.2 pg/mL, which is used as the cutoff for diagnosis of myocardial infarction, and 22 patients (15.4%) had an intermediate value between 5.0 and 26.2 pg/mL. Multivariable regression analysis showed that significant predictors of the hsTnI value were age (β = 0.20, p = 0.01) and BNP (β = 0.43, p < 0.0001) (R² = 0.27, F = 26.0, p < 0.0001), and significant predictors of the BNP value were age (β = 0.23, p = 0.001), hemoglobin (β = -0.43, p < 0.0001), free T₄ (FT₄) (β = 0.23, p = 0.001), and hsTnI (β = 0.27, p < 0.0001) (R² = 0.49, F = 33.8, p < 0.0001). Correlations were found between a decrease in hsTnI and BNP in the first 3 months (ρ = 0.49, p < 0.0001). A decrease in FT₄ in the first 3 months was weakly correlated with decreases in hsTnI (ρ = 0.32, p = 0.0004) and BNP (ρ = 0.32; p = 0.0003). Of the 27 patients with elevated hsTnI (≥5.0 pg/mL), the hsTnI level was normalized in 20 patients within a year.

CONCLUSIONS

In thyrotoxicosis, the myocardial biomarker hsTnI is elevated in about 20% of patients; hsTnI levels decrease as thyroid function improves and BNP decreases.

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.

Analysis of Antithyroid Drug-Induced Severe Liver Injury in 18,558 Newly Diagnosed Patients with Graves' Disease in Japan

Background: The prevalence of antithyroid drug (ATD)-related drug-induced liver injury (DILI) has been reported to vary among patients in several countries. The purpose of this study was to summarize the prevalence of liver injury induced by ATD and to determine the actual prevalence of severe liver injury. Methods: The medical records of 18,558 patients who were newly diagnosed with Graves' disease between January 2005 and December 2016 were retrospectively reviewed. Severe DILI was defined as alanine aminotransferase (ALT) 8 times higher than the upper limit of normal (ULN) or total bilirubin (T-bil) 3 times higher than the ULN. The most severe DILI was defined as ALT higher than 20 times the ULN or T-bil higher than 10 times the ULN. Results: A total of 461 subjects (470 cases) were analyzed, and they consisted of 10 males and 451 females, with a median age of 37 years (range 10-82 years). Nine of 461 patients had severe DILI with both drugs. The total prevalence of severe DILI in this study was 2.5%, and the prevalence of DILI by drug was 1.4% with metimazole (MMI) (n = 198) and 6.3% with propylthiouracil (PTU) (n = 272) (p < 0.001). The prevalence of the most severe ATD-related DILI was 0.22% (n = 40), and the prevalence for each drug was 0.08% with MMI (n = 11) and 0.68% with PTU (n = 29). The median time to DILI development was 30 days (range 7-314 days), and all patients recovered from DILI, with no fatalities. The prevalence of MMI-related DILI was significantly age dependent (p < 0.001). Conclusions: Though there were no fatalities in this study, the prevalence of PTU-related severe DILI was significantly higher than that of MMI-related severe DILI.

Incidence of Neonatal Hyperthyroidism Among Newborns of Graves' Disease Patients Treated with Radioiodine Therapy

BACKGROUND

The serum thyrotropin receptor antibody (TRAb) titers of Graves' disease (GD) patients are known to increase after radioiodine (RAI) therapy, and they can remain high for years. The incidence of neonatal hyperthyroidism (NH) among newborns of mothers with GD who conceived after RAI therapy has not been previously reported. The aims of this study were to investigate the incidence of NH among newborns of mothers who conceived within two years after RAI therapy, and to identify predictors of NH.

METHODS

GD patients (n = 145) who conceived within two years after RAI therapy were retrospectively reviewed, and information regarding their newborns was collected.

RESULTS

Of the 145 pregnant women, 54 (37%) were treated with antithyroid drugs or potassium iodide for maternal hyperthyroidism during the first trimester. There were eight newborns with NH, resulting in an incidence of 5.5%. Seven of the eight mothers whose newborns had NH were treated with antithyroid drugs or potassium iodide during their pregnancy. The incidence of NH among the newborns of mothers who conceived within 6-12 months after RAI therapy was 8.8%, within 12-18 months was 5.5%, and within 18-24 months was 3.6%. Multivariate analysis revealed that the TRAb values in the third trimester were the only risk factor for NH. The cutoff TRAb value in the third trimester for predicting NH was 9.7 IU/L (reference value <2.0 IU/L).

CONCLUSIONS

The incidence of NH among newborns of mothers who conceived within two years after RAI therapy was 5.5%. The fetuses of pregnant GD patients whose TRAb value is high in the third trimester should be carefully followed by an obstetrician during pregnancy, and the newborns should be carefully followed by a pediatrician after birth.

Clinical course of thyroid function and thyroid associated-ophthalmopathy in patients with euthyroid Graves' disease

Background

Euthyroid Graves’ disease (EGD) is a rare condition defined as the presence of thyroid-associated ophthalmopathy (TAO) in patients with normal thyroid function. Due to the rarity of this disease, only a limited number of studies and case reports are available for further evaluation of the characteristics of the disease. The aim of this study was to examine the changes in the thyroid function, thyrotropin receptor antibodies (TRAb) and eye symptoms, and then determine whether TRAb is related to TAO in EGD patients. TRAb in this study was defined as including both thyrotropin-binding inhibitory immunoglobulin (TBII) and thyroid-stimulating immunoglobulin (TSAb).

Patients and methods

Medical records of patients diagnosed with EGD were reviewed. Ophthalmologists specializing in TAO examined the eyes of all subjects.

Results

Of the 58 patients diagnosed with EGD, 24.1% developed hyperthyroidism, while 3.4% developed hypothyroidism. A total of 72.4% of the 58 patients remained euthyroid throughout the entire follow-up period. At the initial presentation, TBII and TSAb were positive in 74.5% and 70.5%, respectively. Ophthalmic treatments were administered to 30 (51.7%) out of the 58 patients. A significant spontaneous improvement of the eye symptoms was found in 28 of the EGD patients who did not require eye treatments. EGD patients exhibited positive rates for both TBII and TSAb, with the number of the TRAb-positive patients gradually decreasing while the eye symptoms spontaneously improved over time. There were no correlations found between TRAb at initial presentation and the eye symptoms.

Conclusion

TBII and TSAb were positive in about 70% of EGD patients at their initial visit. Thyroid functions of EGD patients who have been euthyroid for more than 6.7 years may continue to remain euthyroid in the future.

Seasonal Changes in Serum Thyrotropin Concentrations Observed from Big Data Obtained During Six Consecutive Years from 2010 to 2015 at a Single Hospital in Japan

BACKGROUND

This study analyzed big data for serum thyrotropin (TSH), free triiodothyronine (fT3), and free thyroxine (fT4) concentrations in patients who had attended the outpatient clinic of Ito Hospital (Tokyo, Japan) during a recent six-year period (between January 1, 2010, and December 31, 2015) in order to investigate for seasonal changes.

METHODS

The serum TSH concentrations were reviewed for all 135,417 patients aged >20 years. Patients with any thyroid diseases were included, irrespective of whether they were receiving drug therapy. In total 1,637,721 serum samples were analyzed for TSH, 1,626,269 for fT3, and 1,669,381 for fT4.

RESULTS

It was observed that the TSH concentrations showed annual changes during the six-year period. They decreased during the summer, while they increased during the winter. The TSH concentrations were negatively correlated with the daily temperatures (Spearman rank correlation coefficient -0.4486; p < 0.0001). The same applied for the correlation between fT3 concentrations and daily temperatures.

CONCLUSIONS

The fact that the TSH concentrations show annual changes in areas where the temperature ranges during the year are rather wide should be borne in mind for interpretation of results.

Long-Term Outcomes of 107 Cases of Primary Thyroid Mucosa-Associated Lymphoid Tissue Lymphoma at a Single Medical Institution in Japan

CONTEXT

Thyroid mucosa-associated lymphoid tissue (MALT) lymphoma is a type of extranodal lymphoma with a favorable prognosis.

OBJECTIVE

To provide information on long-term outcomes that would facilitate establishment of the optimal management strategy for thyroid lymphoma.

DESIGN, SETTING, AND PARTICIPANTS

Medical records of 107 patients (median age 67 years, 20 males, 87 females) who were diagnosed with localized thyroid MALT lymphoma stage IE or IIE at Ito Hospital were retrospectively reviewed.

MAIN OUTCOME MEASURE

Overall and event-free survival (EFS).

RESULTS

Initial treatments included radiation therapy (RT) alone (n = 58), combined modality therapy (CMT) (n = 48), or chemotherapy alone (n = 1). All 107 patients responded to the treatment, six of whom experienced relapse. Only one patient died of lymphoma. The 5-year overall survival (OS) and EFS rates were 94% [95% confidence interval (CI), 87% to 97%] and 92% (95% CI, 85% to 95%), respectively, and the 10-year OS and EFS rates were 91% (95% CI, 83% to 95%) and 84% (95% CI, 74% to 90%), respectively. Of the 106 patients with information available on adverse events, 71 patients (67%) developed hypothyroidism after primary thyroid lymphoma treatment. The CMT group showed additional chemotherapy-induced adverse reactions in the form of neutropenia, neuropathy, constipation, and pneumonia. The 5-year OS rates of patients treated with CMT and RT were 93% (95% CI, 81% to 98%) and 94% (95% CI, 84% to 98%), respectively.

CONCLUSIONS

Long-term outcomes of localized thyroid MALT lymphoma are favorable with all initial treatment modalities.

Guidelines for the treatment of childhood-onset Graves' disease in Japan, 2016

Purpose behind developing these guidelines: Over one decade ago, the “Guidelines for the Treatment of Graves’ Disease with Antithyroid Drug, 2006” (Japan Thyroid Association (JTA)) were published as the standard drug therapy protocol for Graves’ disease. The “Guidelines for the Treatment of Childhood-Onset Graves’ Disease with Antithyroid Drug in Japan, 2008” were published to provide guidance on the treatment of pediatric patients. Based on new evidence, a revised version of the “Guidelines for the Treatment of Graves’ Disease with Antithyroid Drug, 2006” (JTA) was published in 2011, combined with the “Handbook of Radioiodine Therapy for Graves’ Disease 2007” (JTA). Subsequently, newer findings on pediatric Graves’ disease have been reported. Propylthiouracil (PTU)-induced serious hepatopathy is an important problem in pediatric patients. The American Thyroid Association’s guidelines suggest that, in principle, physicians must not administer PTU to children. On the other hand, the “Guidelines for the Treatment of Graves’ Disease with Antithyroid Drug, 2011” (JTA) state that radioiodine therapy is no longer considered a “fundamental contraindication” in children. Therefore, the “Guidelines for the Treatment of Childhood-Onset Graves’ Disease with Antithyroid Drug in Japan, 2008” required revision.

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 (β = 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.

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.

Substituting Potassium Iodide for Methimazole as the Treatment for Graves' Disease During the First Trimester May Reduce the Incidence of Congenital Anomalies: A Retrospective Study at a Single Medical Institution in Japan

BACKGROUND

To control hyperthyroidism due to Graves' disease, antithyroid drugs should be administered. Several studies have shown that exposure to methimazole (MMI) during the first trimester of pregnancy increases the incidence of specific congenital anomalies that are collectively referred to as MMI embryopathy. Congenital anomalies associated with exposure to propylthiouracil (PTU) have also recently been reported.

METHODS

This study investigated whether substituting potassium iodide (KI) for MMI in the first trimester would result in a lower incidence of major congenital anomalies than continuing treatment with MMI alone. The cases of 283 women with Graves' disease (GD) were reviewed whose treatment was switched from MMI to KI in the first trimester (iodine group), as well as the cases of 1333 patients treated with MMI alone (MMI group) for comparison. Another major outcome of interest was the incidence of neonatal thyroid dysfunction. The subjects of the analysis of major congenital anomalies and neonatal thyroid dysfunction were live-born infants.

RESULTS

The incidence of major anomalies was 4/260 (1.53%) in the iodine group, which was significantly lower than the incidence of 47/1134 (4.14%) in the MMI group. Two neonates in the iodine group had anomalies consistent with MMI embryopathy (0.8%), as opposed to 18 neonates in the MMI group (1.6%). None of the neonates exposed to KI had thyroid dysfunction or goiter.

CONCLUSIONS

Substituting KI for MMI as a means of controlling hyperthyroidism in GD patients during the first trimester may reduce the incidence of congenital anomalies, at least in iodine-sufficient regions.

Radioiodine-Associated Exacerbation of Graves' Orbitopathy in the Japanese Population: Randomized Prospective Study

CONTEXT

Exacerbation of Graves' orbitopathy (GO) after radioiodine (RAI) therapy has been examined in some populations but has not been fully described in Japanese populations.

OBJECTIVE

The purpose of this study was to clarify the characteristics of GO exacerbation after RAI therapy and the effectiveness of low-dose prophylactic corticosteroid (PCS).

DESIGN AND SETTING

This was a prospective randomized study in Tokyo, Japan.

PATIENTS

Between June 2011 and June 2012, 295 patients with Graves' disease with either inactive GO or no GO received RAI therapy. Of these, 147 received no PCS (PCS-Off group), whereas 148 received low-dose PCS (starting dose, 15 mg/day of prednisolone) for 6 weeks (PCS-On group). We used magnetic resonance imaging to thoroughly evaluate GO before and 1 year after RAI therapy.

MAIN OUTCOME MEASURES

Outcomes of GO 1 year after RAI therapy were determined.

RESULTS

GO exacerbation occurred in 29 patients (9.8%), and only 7 patients (2.4%) required ophthalmic treatment. No significant difference in the frequency of GO exacerbation was seen between the groups (PCS-On group: n = 18 [12.1%]; PCS-Off group: n = 11 [7.5%]; P = .17). Significant prognostic factors were identified as thyroid-stimulating antibody (by 100% linear increase: risk ratio, 1.15; 95% confidence interval, 1.07-1.24; P = .0003) and clinical activity score (≥1 vs 0: risk ratio, 6.40; 95% confidence interval, 2.17-19.7; P = .0009).

CONCLUSION

Exacerbation of GO after RAI therapy in the Japanese population appears less common than in other populations. Low-dose PCS did not produce a significant preventive effect and appeared insufficient. Patients presenting with risk factors would thus be recommended to receive higher-dose PCS.

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.

Rituximab-including combined modality treatment for primary thyroid lymphoma: an effective regimen for elderly patients

BACKGROUND

Primary thyroid lymphoma (PTL) develops mostly in middle-aged and older females. However, the optimal treatment for elderly patients with diffuse large B-cell lymphoma (DLBCL), which accounts for most PTL cases, is unclear. Rituximab is a promising drug that, in combination with traditional combination therapy, has demonstrated an increased antitumor effect without a substantial increase in toxicity. In this study, treatment outcomes of elderly patients with thyroid DLBCL who underwent rituximab-including combination therapy were analyzed.

METHOD

Between January 2005 and December 2011, 43 patients 60 years of age or older (median 71 years, range 60-80 years) were diagnosed as having stage IE (n=12) or stage IIE (n=31) DLBCL, and three courses of R-CHOP therapy (rituximab 375 mg/m2, cyclophosphamide 750 mg/m2, adriamycin 40 mg/m2, vincristine 1.4 mg/m2, and prednisolone 100 mg/body) and involved field irradiation were planned. Treatment outcomes of these patients were retrospectively reviewed.

RESULTS

Two patients terminated the treatment because of interstitial pneumonia during R-CHOP therapy. Only one patient showed treatment resistance and the regimen was changed; 42 patients (98%) responded to the treatment. Five-year overall survival and event-free survival were 87% (95% confidence interval [95% CI], 64-96%) and 74% (95% CI, 50-89%), respectively.

CONCLUSION

The results of the present study indicate that rituximab-including combination therapy was effective for elderly patients with thyroid DLBCL. A multicenter, long-term observational study is needed to confirm this, and additional refinement of the treatment protocol is required to optimize the antitumor effect.

Characteristics of agranulocytosis as an adverse effect of antithyroid drugs in the second or later course of treatment

BACKGROUND

Agranulocytosis is a serious adverse effect of antithyroid drugs (ATDs) and mainly develops within three months after the start of uninterrupted ATD treatment. Agranulocytosis can also develop for the first time after interruption and subsequent resumption of the same ATD treatment. However, little is known with regard to agranulocytosis that develops after resumption of the same ATD treatment.

OBJECTIVES

We investigated the characteristics of patients who developed agranulocytosis during their second or later course of ATD treatment.

METHODS

A total of 81 patients at our hospital were diagnosed with ATD-induced agranulocytosis. In 14 of the cases (methimazole (MMI), n=10; propylthiouracil (PTU), n=4), the agranulocytosis developed for the first time in the context of the second or later course of treatment with the same ATD; those patients were designated the "resumed group." The 35 patients (MMI, n=28; PTU, n=7) who developed agranulocytosis during their first uninterrupted course of ATD therapy were designated the "first group."

RESULTS

The median total duration of ATD treatment before the diagnosis of agranulocytosis was 559 days (range 86-1775 days), and the median interval between the final day of the previous course and the first day of the course in which agranulocytosis was diagnosed was 916.5 days (range 153-8110 days). There were no cases in which agranulocytosis developed when treatment with the same ATD was resumed after discontinuation for less than five months. The difference between the start of ATD treatment in the course in which agranulocytosis was diagnosed and the time interval at which agranulocytosis was diagnosed was similar when comparing the first group and the resumed group (39 (20-98) days in the first group vs. 32.5 (21-95) days in the resumed group; n.s.). There were no significant differences between the groups in terms of granulocyte count at the time agranulocytosis was diagnosed, mortality rate, or the interval between the diagnosis of agranulocytosis and recovery.

CONCLUSIONS

When ATD treatment is resumed, patient follow-up is essential in order to monitor for the development of agranulocytosis.

Antithyroid drug treatment for graves' disease in children: a long-term retrospective study at a single institution

BACKGROUND

The management of Graves' disease (GD) in children is associated with a dilemma. Although the established initial treatment for GD in children is antithyroid drug (ATD) treatment, the remission rate in children is said to be lower than in adults, and severe propylthiouracil-induced adverse events (AEs) are an issue. Definitive treatments are effective, but they often result in permanent hypothyroidism and the need for lifelong T4 supplementation.

OBJECTIVE

The objective of this study was to investigate the outcome of ATD treatment, identify significant predictors of a remission, and evaluate the AEs of ATDs in a large pediatric population of GD patients.

METHODS

We retrospectively assessed the reports of 1138 children up to 18 years of age who had been newly diagnosed with GD at our institution between 1982 and 2006. Their median age at diagnosis was 16 years (range: 3-18 years), and there were 995 females and 143 males. All patients were initially treated with an ATD. Remission was defined as maintenance of euthyroidism for more than 12 months after discontinuing ATD treatment and the absence of any relapses during the follow-up period.

RESULTS

Of the 1138 patients, 723 continued on ATD treatment, 271 underwent surgery or radioactive iodine therapy, and 144 dropped out. Of the 723 patients who continued on ATD treatment, ATD treatment was subsequently ongoing in 84 and was discontinued in 639 (median duration of treatment: 3.8 years; range: 0.3-24.8 years). Of the 639 patients who discontinued ATD treatment, 334 (46.2%) achieved a remission, 247 (34.2%) experienced a relapse, and 58 (8.0%) dropped out. The cumulative remission rate increased with the duration of ATD treatment up until five years. No significant predictors of a remission were identified. The overall incidences of AEs associated with methimazole and propylthiouracil were 21.4% and 18.8% respectively. There were no fatal AEs in our population. While most AEs (91.6%) occurred within the first three months of ATD treatment, 2.7% developed more than two years after the start of ATD treatment. Seven of the eight late-onset AEs were induced by propylthiouracil.

CONCLUSION

Long-term ATD treatment is a useful treatment option for GD in children.

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.

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.

Treatment of graves' disease with antithyroid drugs in the first trimester of pregnancy and the prevalence of congenital malformation

BACKGROUND

Several reports have suggested that propylthiouracil (PTU) may be safer than methimazole (MMI) for treating thyrotoxicosis during pregnancy because congenital malformations have been associated with the use of MMI during pregnancy.

OBJECTIVES

We investigated whether in utero exposure to antithyroid drugs resulted in a higher rate of major malformations than among the infants born to a control group of pregnant women.

METHODS

We reviewed the cases of women with Graves' disease who became pregnant. The pregnancy outcomes of 6744 women were known, and there were 5967 live births. MMI alone had been used to treat 1426 of the women, and 1578 women had been treated with PTU alone. The 2065 women who had received no medication for the treatment of Graves' disease during the first trimester served as the control group. The remaining women had been treated with potassium iodide, levothyroxine, or more than one drug during the first trimester. The antithyroid drugs were evaluated for associations with congenital malformations.

RESULTS

The overall rate of major anomalies in the MMI group was 4.1% (50 of 1231), and it was significantly higher than the 2.1% (40 of 1906) in the control group (P = 0.002), but there was no increase in the overall rate of major anomalies in the PTU group in comparison with the control group (1.9%; 21 of 1399; P = 0.709). Seven of the 1231 newborns in the MMI group had aplasia cutis congenita, six had an omphalocele, seven had a symptomatic omphalomesenteric duct anomaly, and one had esophageal atresia. Hyperthyroidism in the first trimester of pregnancy did not increase the rate of congenital malformation.

CONCLUSIONS

In utero exposure to MMI during the first trimester of pregnancy increased the rate of congenital malformations, and it significantly increased the rate of aplasia cutis congenita, omphalocele, and a symptomatic omphalomesenteric duct anomaly.

A novel role for Niemann-Pick disease type 2C protein in papillae formation

Background

Despite the presence of papillary structures and papillary tumors in humans, the mechanism of papillae formation is unknown. We describe herein a novel role for Niemann-Pick disease type 2C (NPC2) protein, a cholesterol binding protein in the lysosome, in papillae formation.

Methodology/Principal Finding

We examined NPC2 protein expression in surgical samples of papillary tissues by immunohistochemical stain, and all papillary tissues expressed NPC2 protein in the epithelium. To examine our hypothesis of NPC2 protein-mediated papillae formation, we carried out xenograft experiments using wild H460 cells (large cell lung carcinoma cell line) that constitutively expressed abundant NPC2 protein and NPC2 protein-depleted H460 cells by NPC2 shRNA. The xenografts of wild H460 cells and empty shRNA vector cells showed distinct papillae formation, whereas NPC2 protein-depleted H460 cells displayed markedly reduced or no papillae. Since all papillary tissues have open spaces we examined whether NPC2 protein might also contribute to the creation of open spaces. The TUNEL assay in the xenografts of wild and empty shRNA vector H460 cells showed massive cell death, and NPC2 protein-depleted cells displayed minimal cell death. Measurement of caspase 3/7 activities in cultured H460 cells supported NPC2 protein-mediated apoptotic cell death. The presence of excess NPC2 protein, however, did not always produce papillae as seen in the xenografts of CHO cells that were stably transfected with NPC2.

Conclusions/Significance

The NPC2 protein of certain cells forms papillae coupled with apoptosis that creates open space. This protein may have future applications to modulate papillae formation and papillary growth in tumor tissues.

Severe thyroid-associated orbitopathy in Hashimoto's thyroiditis. Report of 2 cases

Thyroid-associated orbitopathy (TAO) is characterized by immune-mediated inflammation of the extraocular muscles surrounding orbital connective tissue and adipose tissue. Severe orbitopathy related to autoimmune thyroid disease often occurs in patients with Grave's disease, but it is rare in patients with Hashimoto's thyroiditis. The pathogenesis of TAO is unclear. Several studies have noted a strong correlation between the levels of antibodies to thyrotropin receptor antibody (TRAb) and TAO in Graves' disease. Mild upper eyelid retraction has been reported to be common in Hashimoto's thyroiditis patients, however severe orbitopathy is rare. We report two cases of severe TAO in patients with Hashimoto's thyroiditis who required systemic glucocorticoid therapy and orbital irradiation to treat the TAO. The activity of the TAO was high in both patients, because their clinical activity scores (CAS) for the orbitopathy were high, and magnetic resonance imaging (MRI) showed enlargement of the extraocular muscles and an increase in T2 signal intensity and prolonged T2 relaxation time which indicate an active stage of inflammation. We tested the presence of TRAb by three different assays and were negative in both patients. Since the eye muscle damage cannot be due to TSH receptor antibodies, other pathogenetic mechanisms may be responsible for the orbitopathy in patients with Hashimoto's thyroiditis.

Reference limits for serum thyrotropin in a Japanese population

The aim of the present study was to establish new reference intervals for serum thyrotropin (TSH) levels in Japanese subjects without antithyroid antibodies. We reviewed the serum TSH level of all patients 20 years of age and over who attended the outpatient clinic of our hospital between January 1, 2003, and September 20, 2010. The thyroid gland of every patient was examined by ultrasonography, and subjects found to have a normal thyroid were chosen. The following subjects were excluded: subjects with past history of thyroid diseases; subjects whose serum was positive for antithyroid antibodies; pregnant women; patients taking medication that might affect their free thyroxine (fT(4)) level or TSH levels. Ultimately, 1388 subjects were included in the reference population. The serum TSH levels shifted to higher ranges as the age of the groups increased. The calculated reference range was 0.39-4.29 mIU/L in the 20-29-year-old group, 0.34-3.90 mIU/L in the 30-39-year-old group, 0.56-5.02 mIU/L in the 40-49-year-old group, 0.51-5.30 mIU/L in the 50-59-year-old group, 0.60-4.85 mIU/L in the 60-69-year-old group, 0.62-6.15 mIU/L in the over 70-year-old group. The results of this study showed that the upper limit of the normal range of serum TSH levels increased with age in a Japanese population. Since the number of elderly reference subjects was relatively small, further study is needed. Setting the age- and race-specific reference limits for serum TSH levels is important in order to prevent significant misclassifications of patients with abnormal TSH levels.

Dual oxidase, hydrogen peroxide and thyroid diseases

The thyroid gland is a unique endocrine organ that requires hydrogen peroxide (H(2)O(2)) for thyroid hormone formation. The molecule for H(2)O(2) production in the thyroid gland has been known as dual oxidase 2 (DUOX2). Recently, NADPH oxidase 4 (NOX4), a homolog of the NOX family, was added as a new intracellular source of reactive oxygen species (ROS) in the human thyroid gland. This review focuses on the recent progress of the DUOX system and its possible contribution to human thyroid diseases. Also, we discuss human thyroid diseases related to abnormal H(2)O(2) generation. The DUOX molecule contains peroxidase-like and NADPH oxidase-like domains. Human thyroid gland also contains DUOX1 that shares 83% similarity with the DUOX2 gene. However, thyroid DUOX1 protein appears to play a minor role in H(2)O(2) production. DUOX proteins require DUOX maturation or activation factors (DUOXA1 or 2) for proper translocation of DUOX from the endoplasmic reticulum to the apical plasma membrane, where H(2)O(2) production takes place. Thyroid cells contain antioxidants to protect cells from the H(2)O(2)-mediated oxidative damage. Loss of this balance may result in thyroid cell dysfunction and thyroid diseases. Mutation of either DUOX2 or DUOXA2 gene is a newly recognized cause of hypothyroidism due to insufficient H(2)O(2) production. Papillary thyroid carcinoma, the most common thyroid cancer, is closely linked to the increased ROS production by NOX4. Hashimoto's thyroiditis, a common autoimmune thyroid disease in women, becomes conspicuous when iodide intake increases. This phenomenon may be explained by the abnormality of iodide-induced H(2)O(2) or other ROS in susceptible individuals. Discovery of DUOX proteins and NOX4 provides us with valuable tools for a better understanding of pathophysiology of prevalent thyroid diseases.

Extent of hypoechogenic area in the thyroid is related with thyroid dysfunction after subacute thyroiditis

OBJECTIVE

To gain an insight into risk factors for hypothyroidism after subacute thyroiditis (SAT), we examined the correlation between initial laboratory and ultrasonographic findings and sequential thyroid dysfunction among treatment modalities.

PATIENTS

We reviewed retrospectively the medical records of 252 patients (26 men and 226 women) with SAT who consecutively visited our thyroid clinic at Kuma Hospital for at least 6 months from 1996 through 2004.

RESULTS

Throughout the course, 135 patients (53.6%) developed transient or permanent hypothyroidism. Levels of TSH were most often elevated (greater than 5 IU/ml) 2 months after SAT onset regardless of treatment, and 97.0% of patients who showed transient or permanent hypothyroidism clustered within 6 months from onset. During follow-up, patients treated with prednisone (PSL) were more likely to have normal thyroid function than patients not treated or those receiving anti-inflammatory drug therapy. In patients who developed hypothyroidism with PSL treatment or without treatment, the rates of bilateral hypoechogenic areas (HEA) were 6-fold higher than those of unilateral HEA. Moreover, permanent hypothyroidism occurred in 5.9% of patients, and all patients with permanent hypothyroidism presented initially with bilateral HEA and had consequently small thyroid size with or without abnormal autoimmunity.

CONCLUSIONS

The rates of thyroid dysfunction after SAT were significantly lower in patients receiving PSL. Extent of HEA in the thyroid, but not laboratory findings, may be a possible marker for developing thyroid dysfunction after SAT.

Papillary carcinoma obscured by complication with subacute thyroiditis: sequential ultrasonographic and histopathological findings in five cases

BACKGROUND

Subacute thyroiditis (SAT) has been rarely reported to coexist with thyroid carcinomas. The objective of the study was to assess sequential ultrasonographic and histopathological findings of SAT in the context of complicating thyroid carcinomas.

METHODS

Of 1152 patients with SAT who visited our thyroid clinic at Kuma Hospital from 1996 through 2006, 5 cases complicated by papillary carcinoma underwent surgical resection 3-16 months after SAT onset. Ultrasonographic examinations and thyroid function tests were performed in all patients at onset of SAT and just before surgery. Sequential histopathological features of regenerated thyroid and carcinoma involvement were evaluated.

RESULTS

Heterogenous areas with microcalcifications in the thyroid or lymphadenopathy in three patients were clues for the nodular involvement with papillary carcinoma on the initial ultrasonographic examination. In contrast, diffuse hypoechoic change in the thyroid in two patients made it impossible to differentiate nodular involvement from inflammatory lesion. Histopathological examination of surgical specimens showed granulomatous and fibrotic changes. These were present about 3 months from SAT onset, and residual fibrosis remained several additional months, in the condition of no inflammatory hypoechoic lesions. In the areas of papillary carcinoma overlapping with transient inflammatory involvement, some lymphocytes and fibrotic changes were present in the stroma of papillary foci, but no granulomatous formation was present in any sections. Continuity with fibrosis around regenerated follicular cells was absent. The degree of lymphoid infiltrate and fibrotic change in the papillary carcinoma was not dependent on periods between SAT onset and the resection.

CONCLUSIONS

SAT may produce ultrasound changes that obscure the coexistence of papillary carcinoma, but affects no lymphoid infiltrate and fibrotic changes involved in carcinoma throughout the clinical course. We recommend that patients with SAT have ultrasonography after they recover. Further workup, including cytological examination of hypoechoic regions, should be performed if they are present as measuring 1 cm or larger.

A novel homozygous missense mutation of the dual oxidase 2 (DUOX2) gene in an adult patient with large goiter

OBJECTIVE

To describe the first adult case of large goiter associated with a novel R1110Q mutation in the dual oxidase 2 (DUOX2) gene. She was initially euthyroid, and developed hypothyroidism later in her forties. DUOX2 is an essential enzyme in iodine organification of thyroid hormone biosynthesis. Only infant cases of congenital hypothyroidism due to mutations of the DUOX2 gene have been reported. Biallelic mutation of DUOX2 is thought to lead to total iodine organification defect. PATIENTS AND MEASUREMENT: This 57-year-old woman became first aware of goiter around the age of 20 years. Since the goiter had enlarged gradually, she consulted us at the age of 32 years. Goiter was soft, and thyroid function was normal. Antithyroid antibodies were negative. Both physical and mental development was normal. Three of her nine siblings and her mother had large goiters. At the age of 44 years, thyroid function demonstrated subclinical hypothyroidism. She started to take levo-thyroxine at a dose of 100 mug/day to reduce goiter. At the age of 56 years, goiter size remained the same. The perchlorate discharge rate was 72.8%, suggesting partial iodine organification defect. Thus, thyroid peroxidase (TPO) gene and DUOX2 gene were analyzed.

RESULTS

There was no mutation in the TPO gene, but a novel homozygous mutation (R1110Q) in the DUOX2 gene was identified. The same heterozygous mutation was detected in her two sons and two grandchildren. This mutation was not detected in 104 control alleles and was located at a site differing from any other reported mutations in the DUOX2 gene.

CONCLUSIONS

This homozygous missense mutation can be associated with thyroid dysfunction and goiter formation of an enlarged thyroid gland.

Serial changes in liver function tests in patients with thyrotoxicosis induced by Graves' disease and painless thyroiditis

CONTEXT

When the liver function tests are aggravated after starting antithyroid drugs (ATDs) in Graves' hyperthyroidism, discontinuation of ATDs is generally considered. However, a question arises whether such aggravation constitutes an adverse effect of the drugs or not.

OBJECTIVE

The aim of this study was to clarify the influence of thyrotoxicosis on liver function tests, comparing the results with those in thyrotoxicosis induced by painless thyroiditis.

DESIGN

We prospectively studied liver biochemical tests in 30 patients with Graves' disease and in 27 patients with painless thyroiditis.

MAIN OUTCOMES

Twenty-three (76.7%) untreated Graves' disease patients and 14 (51.9%) untreated painless thyroiditis patients were found to have at least one liver function test abnormality. One month after starting ATD therapy in patients with Graves' disease, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) elevations from initial values were observed in 16 (53.3%). Similar elevations of AST and ALT from initial values at 1 month were observed in 10 (37.0%) and 7 (25.9%) patients with painless thyroiditis, respectively. Alkaline phosphatase (ALP) increased gradually after starting ATD therapy and maintained an elevated value for 3-5 months in Graves' disease. In painless thyroiditis, ALP also increased gradually, similarly to that in Graves' disease, but changes were mild. Elevation of ALT after 1 month of ATD therapy in Graves' disease was significantly higher in patients whose estimated disease duration was 6 months or more compared to those with duration of less than 6 months. Elevated AST and ALT at 1 month after ATD therapy decreased to normal ranges, even though patients were receiving the same ATDs in Graves' disease.

CONCLUSION

Similar serial changes in liver function tests in both Graves' disease and painless thyroiditis strongly suggest that increases of AST and ALT after starting ATD therapy may not be due to ATD side effects but may be induced by changes in thyroid function.

The prevalence of transient thyrotoxicosis after antithyroid drug therapy in patients with Graves' disease

BACKGROUND

Although transient thyrotoxicosis occurring after antithyroid drug (ATD) withdrawal in patients with Graves' hyperthyroidism has been reported, the prevalence of transient thyrotoxicosis after ATD therapy is as yet unknown. When patients with transient hyperthyroidism are mistakenly regarded as recurrences, they receive unnecessary therapy. The aim of this study was to investigate the prevalence of transient thyrotoxicosis after ATD withdrawal.

METHODS

We selected 110 consecutive patients with Graves' disease whose ATD therapy was stopped from December 2002 to September 2004 prospectively. Patients were observed for more than 1 year after ATD withdrawal, and 12 patients dropped out. Serum levels of free thyroxine (FT(4)), thyrotropin, and thyrotropin-binding inhibitor immunoglobulin were measured at ATD withdrawal, and 3, 6, and 12 months after withdrawal. When the patients showed mild thyrotoxicosis (serum FT(4) level of less than 3.00 ng/dL), we followed them up for 1 month without medication.

RESULTS

The remission rate of the study group was 61.8% (68/110). Twenty-eight patients became euthyroid after transient thyrotoxicosis, equivalent to 41.2% of the remission patients. Eight of 28 patients showed overt thyrotoxicosis, and the rest subclinical thyrotoxicosis. Transient thyrotoxicosis occurred mostly 3-6 months after ATD withdrawal.

CONCLUSIONS

Transient thyrotoxicosis after ATD withdrawal in patients with Graves' disease is not a rare phenomenon. Clinicians should be aware that the recurrence of Graves' disease after the withdrawal of ATD may be transient.

Clinical characteristics of 852 patients with subacute thyroiditis before treatment

OBJECTIVE

Subacute thyroiditis (SAT) is a transient inflammatory disease of the thyroid. We evaluated the clinical characteristics based on laboratory and imaging studies in patients with SAT before treatment.

PATIENTS

We reviewed the medical records of 852 patients (107 men and 745 women) with SAT who visited our thyroid clinic at Kuma Hospital from 1996 through 2004.

RESULTS

SAT developed most often in female patients aged 40 to 50 years, with significant seasonal clusters during summer to early autumn. While the rates of any virus infections and diseases did not differ from those in the general population, recurrent episodes of SAT at intervals of 13.6+/-5.6 years accounted for 1.6% of all cases. At the onset of SAT, 28.2% of patients had temperatures greater than 38 degrees C and typical symptoms associated with thyrotoxicosis developed in more than 60% of patients. Before treatment, most of the abnormal laboratory findings associated with thyrotoxicosis, inflammation, and liver dysfunction reached peak levels within 1 week after onset. Ultrasound examination showed that half of the patients with unilateral thyroid pain presented with bilateral hypoechogenic area in the thyroid and the rate of bilateral hypoechogenic area tended to increase 2 months after onset.

CONCLUSION

Laboratory studies of thyroid dysfunction and inflammation related to SAT presented peak levels within 1 week after onset.

[Malignant lymphoma of the thyroid]

Primary malignant lymphoma of thyroid is frequently associated with Hashimoto's thyroiditis and it is usually non-Hodgkin type. Thyroid lymphoma is common in women and the mean age at onset is 60 years old. The main symptom is rapidly growing goiter. The majority of histopathologic types are extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue, diffuse large B-cell lymphoma, and mixed type of above two. If the findings on ultrasonography and fine needle aspiration cytology are suspected thyroid lymphoma, histopathological diagnosis of tissue obtaining from open biopsy is necessary. The treatment for thyroid lymphoma consists of chemotherapy (CHOP), rituximab combined with CHOP, and radiation therapy. It is selected based on the histopathologic type and the extent of disease. The prognosis depends on the histopathologic type and the staging. It should be recognized that early diagnosis and correct treatment lead to favorable prognosis.

Effect of levo-thyroxine replacement on non-high-density lipoprotein cholesterol in hypothyroid patients

CONTEXT

Recently, non-high-density lipoprotein cholesterol (non-HDL-C), a measure of total cholesterol minus HDL-C, has emerged as a predictor of cardiovascular disease.

OBJECTIVE

We evaluated the effect of L-T4 replacement on non-HDL-C levels in patients with primary hypothyroidism.

METHODS

Thirteen patients with overt hypothyroidism and 26 patients with subclinical hypothyroidism participated in the study. The lipid profiles, including non-HDL-C, were measured in patients with hypothyroidism before and 3 months after L-T4 replacement was started.

RESULTS

After L-T4 replacement, the serum concentrations of all lipoproteins, exclusive of lipoprotein (a) [Lp(a)], were significantly decreased in patients with overt hypothyroidism. In patients with subclinical hypothyroidism, the serum concentrations of total cholesterol, non-HDL-C, remnant-like particle cholesterol, and apolipoprotein B (Apo B) were significantly decreased, whereas no significant changes in the serum concentrations of low-density lipoprotein cholesterol, HDL-C, triglycerides, apolipoprotein A-I, and Lp(a) were observed. In all 39 patients, the reduction in the non-HDL-C levels correlated with the reduction in the low-density lipoprotein cholesterol, remnant-like particle cholesterol, and Apo B levels. However, the reduction in the non-HDL-C levels did not correlate with the reduction in the HDL-C, Lp(a), and apolipoprotein A-I levels.

CONCLUSIONS

This study is the first to show that L-T4 replacement may reduce serum concentrations of non-HDL-C in patients with hypothyroidism. The study also suggests that such altered serum concentrations of non-HDL-C in hypothyroidism may be related to the disturbed metabolism of low-density lipoprotein, remnant lipoprotein, and Apo B.

Sustained fever resolved promptly after total thyroidectomy due to huge Hashimoto's fibrous thyroiditis

We encountered a 55-year-old female patient with Hashimoto's thyroiditis who showed persistent fever, and could not find any source of fever other than the large nontender goiter. Her fever continued with positive CRP for 6 months. Although we did not assume that the inflammation was related to Hashimoto's thyroiditis, total thyroidectomy was performed for cosmetic reasons; however, fever was resolved immediately after thyroidectomy. Pathological diagnosis was Hashimoto's chronic thyroiditis. Immunohistochemical staining showed that the follicular cells were positive for IL-1alpha, IL-1beta, and TNF-alpha. We believed that fever was induced by inflammatory cytokines produced in thyroid. The case indicated that Hashimoto's thyroiditis with nontender goiter could cause idiopathic fever.

Sporadic congenital hyperthyroidism due to a germline mutation in the thyrotropin receptor gene (Leu 512 Gln) in a Japanese patient

Constitutively activating thyrotropin receptor (TSHR) germline mutations have been identified as a molecular cause of congenital hyperthyroidism. We here describe a Japanese woman who had presented with severe hyperthyroidism and advanced bone age as a neonate. She underwent neurosurgical intervention for craniosynostosis, and presented with perodactylia and mild mental retardation with hydrocephalus. Hyperthyroidism has been refractory to antithyroid drug therapy in the absence of antithyrotropin receptor antibodies during follow-up of 20 years, resulting in an enlarged goiter. Analysis of the patient's genomic DNA showed a heterozygous thymine-to-adenine point mutation in exon 10 of TSHR at position 1535 which was not present in the parents' DNA. This mutation, changing leucine to glutamine in codon 512 in the third transmembrane region, was previously identified as a somatic mutation in toxic thyroid nodules and was shown to increase basal cAMP production in vitro. To our knowledge, this is the first report of a germline mutation of TSHR causing sporadic congenital nonautoimmune hyperthyroidism in a Japanese patient.

Benign thyroid teratomas manifest painful cystic and solid composite nodules: three case reports and a review of the literature

Benign thyroid teratomas are rare in adolescents and adults. We report on three cases of benign thyroid teratomas that presented as painful tumors in the neck after puberty. The tumor adjacent to the thyroid in each case showed rapid enlargement with predominant cystic lesions within several months. Ultrasonography and computed tomography revealed few findings suggesting the origin of the tumor. Cytological examination and culture of the aspirate failed to show cells originating from the thyroid or infectious findings, but revealed a small population of columnar epithelial cells or squamous epithelial cells. Chemical analysis of the aspirate showed levels of pancreatic enzymes higher than those in serum. The accumulation of cystic fluid in each case was refractory to drainage treatment or percutaneous ethanol injection therapy. The patients subsequently underwent resection of the tumor, and microscopic examination revealed various types of tissue including pancreas, adipose, cartilage, muscle, and skin, and the cystic wall was lined by gastric, intestinal, respiratory, and stratified squamous epithelium. Surgical resection was curative, and subsequent histologic examination revealed mature benign teratomas of the thyroid. The main characteristic of our cases presented the painful tumors due to the enlarged cystic formation lined by a variety of different types of epithelium, which agreed with previous cases of benign thyroid teratomas in adolescents and adults.

Two-day thionamide withdrawal prior to radioiodine uptake sufficiently increases uptake and does not exacerbate hyperthyroidism compared to 7-day withdrawal in Graves' disease

The appropriate period of antithyroid drug (ATD) discontinuation before radioiodine therapy is the most critical problem in Graves' disease patients under going treatment with ATD. To determine the optimal period that does not alter the outcome of radioiodine therapy or exacerbate hyperthyroidism, we compared serum FT4 levels at radioiodine uptake (RAIU) and therapy outcomes between a 2-day withdrawal group and 7-day withdrawal group. We prospectively recruited 43 patients for the 2-day withdrawal protocol and retrospectively reviewed 49 patients treated with radioiodine following the protocol of 7-day withdrawal. There was no significant difference in RAIU between the 2 groups. The mean serum FT4 level measured on the first day of 24-h RAIU of the 7-day group was significantly higher than that in the 2-day group. There were no significant differences in the outcomes at each point (6 months, 1 year, and 2 years after therapy) between the 2 groups. Our results indicated that withdrawal of ATD for 2 days is superior to 7 days in that 2 days discontinuation did not exacerbate hyperthyroidism. In order to prevent serum thyroid hormone increase after ATD withdrawal and radioiodine therapy, a 2-day ATD withdrawal period before radioiodine therapy may be useful for high-risk patients such as the elderly and patients with cardiac complications. We believe that the 2-day ATD withdrawal method may be useful for patients undergoing treatment with ATD who are to undergo radioiodine therapy.

Haplotype analysis reveals founder effects of thyroglobulin gene mutations C1058R and C1977S in Japan

CONTEXT

Thyroglobulin (Tg) mutations were previously believed to be rare, resulting in congenital goitrous hypothyroidism. However, an increasing number of patients with Tg mutations, who are euthyroid to mildly hypothyroid, have been identified in Japan.

OBJECTIVES

The purpose of this study was to investigate whether the three frequently found Tg mutations, namely C1058R, C1245R, and C1977S, were caused by a founder effect.

RESULTS

We found 26 different mutations within the Tg gene in 52 patients from 41 families. Thirty-five patients were homozygous for the mutations, whereas the others were compound heterozygous. The occurrence of Tg mutation within the general Japanese population is one in 67,000. Patients with the C1245R mutation were found throughout Japan, whereas those with the C1058R mutation were confined to a small village on a southern island, and those with the C1977S mutation were restricted to a city. The eight patients with the C1058R mutation and the seven patients with the C1977S mutation all showed the same combinations of 18 single-nucleotide polymorphisms in the coding region of the Tg gene, which would appear in one in 810 million and one in 37 billion, respectively, control subjects.

CONCLUSIONS

The frequently found mutations, C1058R and C1977S, were caused by founder effects. This result suggests that Tg mutations may provide a genetic basis for the cause of familial euthyroid goiter.

A case of hypothyroid Graves' disease following external radiation therapy to the cervical region

A case of hypothyroid Graves' disease occurred following external radiation therapy to the cervical region is described. Severe hypothyroidism developed in a 56-year-old man 6 months after external radiation therapy for submandibular cancer. Serological evaluation of thyroid autoimmunity revealed the presence of antithyroid antibodies and thyrotropin-binding inhibitory immunogloblins (TBII). Diplopia, limitation of downward gaze, and palpebral edema developed 2 years after levothyroxine replacement therapy. Ocular magnetic resonance imaging revealed marked hypertrophy of the bilateral extraocular muscles with signal hyperintensity on T2-weighted images. This infiltrative ophthalmopathy showed marked improvement after additional treatment with high-dose methylprednisolone and orbital radiation, in parallel with a decrease in TBII. These results suggest that radiation-associated thyroidal injury might be associated with the etiology of hypothyroid Graves' disease.

Four cases of Graves' disease which developed after painful Hashimoto's thyroiditis

We report four cases of Graves' disease that developed after painful Hashimoto's thyroiditis. All were middle-aged women, who had high titers of anti-thyroid antibodies and thyrotoxicosis at the onset of painful Hashimoto's thyroiditis. After 2 to 7 years, they developed Graves' disease with positive antibody against the thyrotropin receptor. Their clinical courses of Graves' disease went favorably due to the treatment with antithyroid drug or radioactive iodine therapy. Painful Hashimoto's thyroiditis is an atypical variant of Hashimoto's thyroiditis and is one form of destructive thyroiditis. Thyroid damage due to painful Hashimoto's thyroiditis may be associated with the development of Graves' disease.

Successful use of iodine and levothyroxine to treat Graves' disease in a pregnant patient with allergy to antithyroid drugs and high thyrotropin-binding inhibitor immunoglobulin after radioiodine therapy

High titer of thyrotropin-binding inhibitor immunoglobulin (TBII) in patients with Graves' disease can cause fetal hyperthyroidism during pregnancy. Prevention of fetal hyperthyroidism by administration of antithyroid drug (ATD) and levothyroxine (LT(4)) to pregnant patients who previously received ablative therapy has been reported. We administered iodine and LT(4) to a patient during gestation, because she had a severe adverse reaction to ATD. Although gestation proceeded normally, the infant showed transient neonatal hyperthyroidism right after birth. We believe that the fetus would have developed hyperthyroidism if we had not administered iodine to the mother. Administration of iodine and LT(4) to a pregnant patient with Graves' disease showing a high TBII after ablative therapy should be considered in rare patients with allergy to ATD.

Effect of high dose methylprednisolone pulse therapy followed by oral prednisolone administration on the production of anti-TSH receptor antibodies and clinical outcome in Graves' disease

Little is known about the immunosuppressive effect of glucocorticoids on TSH receptor antibodies. We observed the long-term prognosis and serum TSH binding inhibitor immunoglobulin (TBII) levels in patients with Graves' ophthalmopathy who had received intravenous methylprednisolone pulse therapy (pulse therapy) followed by oral prednisolone administration in order to ascertain how long the immunosuppressive effect of glucocorticoids continued. This is the first report on the effect of pulse therapy on Graves' disease outcome. We observed 67 patients who were treated by antithyroid drugs (ATD) alone for 2 years after pulse therapy. TBII was evaluated before and 3, 6, 12, 18, and 24 months after pulse therapy. The mean TBII decreased significantly 3 months after pulse therapy (p<0.001), and was maintained until 24 months. There were 24 patients whose TBII was positive (>15%) at 24 months, in whom the mean TBII decreased significantly 3 to 6 months after pulse therapy (p<0.001), but increased again at 12 to 24 months (p<0.05). Thus, the immunosuppressive effect of glucocorticoids may be lost at 12 months after pulse therapy in these patients. The remission rate in the pulse therapy group was 40.98%, and that of the control patient group was 48.57%. There was no significant difference between the two. These results suggest that the immunosuppressive effect of pulse therapy was temporary, and that pulse therapy did not increase remission rate of Graves' disease.

Acute suppurative thyroiditis after fine-needle aspiration causing thyrotoxicosis

A case of thyrotoxicosis caused by acute suppurative thyroiditis after repeated fine-needle aspiration (FNA) is described. A 39-year-old woman with atopic dermatitis showed rapid enlargement of a left thyroid cyst after a third FNA. She had a high fever, painful swelling of the left thyroid, and elevated thyroid hormone levels. Ultrasonography revealed abscess formation in the left thyroid cyst. The cytologic examination of an FNA specimen showed abundant neutrophils, and culture of the aspirate yielded Staphylococcus aureus. Because antibiotic treatment for 1 month failed to improve the inflammatory findings, the patient subsequently underwent left thyroid lobectomy, which resulted in the normalization of thyroid function and the resolution of inflammation. Thyroid infection had possibly been induced by needle-track seeding, because atopic skin favors colonization by S. aureus because of local immunologic deficiency. FNA is a useful and safe technique for aspirating fluid from thyroid cysts, but special care is required in patients with atopic dermatatis to avoid bacterial infection.

Thyrotoxicosis Caused by Weight-Reducing Herbal Medicines

The weight-reducing herbal medicines "Dream Shape" and "Ever Youth" became available in Japan in 2000. Herein, we describe 12 patients who developed thyrotoxicosis after taking them. The thyroid hormone content of 1 capsule or tablet of herbal medicine, measured following Pronase digestion and ethanol extraction, was approximately 1 mug of triiodothyronine and 3 to 4 mug of thyroxine. Two of us took 10 capsules or tablets of Dream Shape or Ever Youth, and changes in thyroid hormone levels were observed during the first 24 hours. Serum free triiodothyronine levels began to rise 2 hours after ingestion and reached peak levels at 4 to 8 hours; changes in free thyroxine and thyrotropin levels were small during the first 24 hours. Similar herbal medicines may have been distributed to other countries via the Internet. Resultant factitious thyrotoxicosis can create diagnostic and therapeutic confusion, particularly in patients with thyroid disease.

Successful treatment for recurrent painful Hashimoto's thyroiditis by total thyroidectomy

Painful Hashimoto's thyroiditis is an atypical variant of Hashimoto's thyroiditis characterized by thyroid pain and fever. In patients with this condition, anti-inflammatory agents are not always effective as in those with subacute thyroiditis. Therefore, long-term pain management is an important issue. We report herein four cases of painful Hashimoto's thyroiditis requiring total thyroidectomy to relieve thyroid pain and histologic findings of the thyroid gland. All patients had high titers of anti-thyroperoxidase (TPO) and thyroglobulin antibodies. Three were hypothyroid, and the other was euthyroid. During the first visit, four patients had fever and/or thyroid pain with elevated C-reactive protein or erythrocyte sedimentation rate, and they were treated with oral corticosteroids given continuously or intermittently for 9 to 48 months. Because a reduction or discontinuation of corticosteroids caused recurrent painful attacks, the decision was made to perform surgery. After total thyroidectomy, their symptoms disappeared. The histopathologic characteristics of these hypothyroid cases were advanced fibrosis and destructive thyroid architecture. One euthyroid case showed a mild fibrous change and the presence of foreign body type giant cells. In conclusion, total thyroidectomy is the effective and reliable treatment for patients with recurrent painful Hashimoto's thyroiditis. Pathologic characteristics include advanced fibrosis and destructive thyroid architecture.

Transient hyperthyroidism after withdrawal of antithyroid drugs in patients with Graves' disease

The development of silent thyroiditis in patients with a history of Graves' disease is common, especially in the postpartum period. We describe herein patients with Graves' disease who developed transient hyperthyroidism but not silent thyroiditis after withdrawal of antithyroid drug (ATD). If such patients are diagnosed as recurrence of Graves' disease, they may receive ATD or radioiodine therapy unnecessarily. We investigated the characteristics of these patients to prevent unnecessary therapy. We retrospectively studied 22 patients with Graves' disease who showed transient thyrotoxicosis after withdrawal of ATD. Two of 22 patients were male and the mean ages (+/- SD) were 33.7 +/- 12.6 yr. We observed these patients for 28.5 +/- 12.8 (mean +/- SD; range 12-53) months after transient thyrotoxicosis, and measured TSH, FT4, and TSH binding inhibitor immunoglobulin in sera. Radioiodine uptake was measured in 6 of them. The radioiodine uptake in the 4 patients was not suppressed (27.5%, 28.0%, 32.7%, 38.1%). These uptake levels indicate that their thyrotoxicosis was not caused by silent thyroiditis. Most of the 22 patients became euthyroid within 6 months. This study suggests a new therapeutic option as follows: in the case of young patients with mild thyrotoxicosis after withdrawal of ATD, physicians should follow them up for one month without medication unless they have unbearable symptoms or complications.

Large goiter and multiple rib tumors

We report an interesting case of a 47-yr-old who had a large goiter and multiple rib tumors. The patient was initially suspected of having thyroid cancer, which had metastasized on the ribs, based on imaging studies. However, laboratory tests revealed a high level of ionized calcium and parathyroid hormone (PTH). The large goiter was diagnosed as having parathyroid tumors owing to the high level of PTH in the tissue fluid. The biopsy specimen from a rib tumor was diagnosed as containing brown tumors associated with primary hyperparathyroidism (PHP). The patient also had prolactinoma and pancreatic gastrinoma. Her daughter had both prolactinoma and PHP, and her brother and her father had PHP. Thus, the patient was diagnosed as having multiple endocrine neoplasia type 1.

Different phenotypes of multiple endocrine neoplasia type 1 (MEN1) in monozygotic twins found in a Japanese MEN1 family with MEN1 gene mutation

We report monozygotic twins who showed different MEN1 phenotypes. The proband (28 y.o., female) had both primary hyperparathyroidism (PHP) and insulinoma, and genetic analysis revealed a point mutation (569del1, exon 3) of the MEN1 gene. This mutation causes a frameshift and produces a stop codon at codon 184. Restriction digestion (HinfI) analysis confirmed the same mutation of the MEN1 gene in six of the affected members including her two sisters, the monozygotic twins, and no such mutation in two unaffected members. In two generations of this family, eight of eleven family members had PHP and four of them were found to have other MEN1-related lesions. Both of the monozygotic twins had PHP. Interestingly, one had pancreatic tumor but the other had no evidence of it. Pituitary MRI showed no pituitary lesion in either of them. This is the first Japanese case of monozygotic twins with different MEN1 phenotypes.

No evidence of germline mutation or somatic deletion of the MEN1 gene in a case of familial multiple endocrine neoplasia type 1 (MEN1)

The MEN1 gene has recently been cloned as the gene responsible for multiple endocrine neoplasia type 1 (MEN1) and its germline mutations have been identified in a number of familial MEN1 patients. However, mutation-negative cases have also been reported in some MEN1 families. We report here a Japanese MEN1 family, including a proband with no evidence of MEN1 gene mutation. The proband (51 y.o., female) had three major MEN1 lesions, including primary hyperparathyroidism (HP), prolactinoma, and pancreatic tumor. Her father and brother had HP, and her daughter had both HP and prolactinoma. When we analyzed the proband for a germline mutation of the MEN1 gene, the direct sequencing analysis showed no mutation in the coding region, on the promoter, 5' and 3' untranslated regions of the MEN1 gene. We next examined the loss of heterozygosity (LOH) in the proband's parathyroid tumors using two benign polymorphisms (C2249G in intron 1 and 2248del3 in exon 10) in the MEN1 gene to detect LOH. LOH was not found in any of the four separate regions of the tumor tissues.