亚临床甲状腺功能紊乱的发病率及病因分析

目的：探讨亚临床甲状腺功能紊乱的发病率及病因。方法：对12592例本地区的门诊及住院病例的甲状腺功能检测的七项指标进行筛查分析。结果：12592例检测者中有874例TSH在异常范围内,检出率为6．94％,其中TSH高于正常者397例,检出率为3．15％,TSH低于正常者477例,检出率为3．79％;874例处于亚临床甲状腺功能紊乱者多见于伴相关甲状腺疾病者,如甲亢治疗后、甲减甲状腺制剂替代治疗中及其他甲状腺病变（甲状腺结节、甲状腺炎）。除外上述因素在无明显疾病的143人中,亚临床甲减者109人（874人中12．47％）,亚临床甲亢者34人（874人中3．89％）。亚临床甲状腺功能紊乱与TGA、TMA多同步上升,升高者269例,发生率为30．78％,其中TSH高于正常者147例,占16．82％,TSH低于正常者122例,占13．96％;874例中≥60岁老年人有256例,检出率为29．29％。结论：临床应重视对亚临床甲状腺功能紊乱的检测,特别是老年人具有较高的发病率。     

Hypothyroidism,new nodule formation and increase in nodule size in patients who have undergone hemithyroidectomy

Introduction

The current medical literature has conflicting results about factors related to hypothyroidism and nodular recurrences during follow-up of hemithyroidectomized patients. We aimed to evaluate factors that may have a role in new nodule formation, hypothyroidism, increase in thyroid lobe and increase in nodule volumes in these patients with and without Hashimoto''s thyroiditis (HT), and with and without levothyroxine (LT4) use.

Material and methods

We enrolled 140 patients from five different hospitals in Ankara and evaluated their thyroid tests, autoantibody titre results and ultrasonographic findings longitudinally between two visits with a minimum 6-month interval.

Results

In patients with HT there was no significant difference between the two visits but in patients without HT, thyroid stimulating hormone (TSH) levels and nodule volume were higher, and free T4 levels were lower in the second visit. Similarly, in patients with LT4 treatment there was no difference in TSH, free T4 levels, or lobe or nodule size between the two visits, but the patients without LT4 had free T4 levels lower in the second visit. Regression analysis revealed a relationship between first visit TSH levels and hypothyroidism during follow-up.

Conclusions

Patients who have undergone hemithyroidectomy without LT4 treatment and without HT diagnosis should be followed up more carefully for thyroid tests, new nodule formation and increase in nodule size. The TSH levels at the beginning of the follow-up may be helpful to estimate hypothyroidism in hemithyroidectomized patients.     

Distribution of immunoglobulin G subclasses of anti-thyroid peroxidase antibody in sera from patients with Hashimoto's thyroiditis with different thyroid functional status

The mechanism of disease progression in Hashimoto's thyroiditis (HT) is still unclear. Anti-thyroid peroxidase antibody (TPOAb), a diagnostic hallmark of HT, is principally of the immunoglobulin G (IgG) isotype, and it appears to be a response to thyroid injury. The aim of our study was to evaluate the distribution of IgG subclasses of TPOAb in sera from patients with HT with different thyroid functional status. Sera from 168 patients with newly diagnosed HT were collected and divided into three groups according to thyroid function: patients with hypothyroidism (n = 66), subclinical hypothyroidism (n = 60) and euthyroidism (n = 42). Antigen-specific enzyme-linked immunosorbent assay was used to detect the distribution of TPOAb IgG subclasses. The prevalence of TPOAb IgG subclasses in all patients' sera with HT was IgG1 70.2%, IgG2 35.1%, IgG3 19.6% and IgG4 66.1% respectively. The prevalence of IgG2 in sera from patients with hypothyroidism (51.5%) was significantly higher than that of subclinical hypothyroidism (33.3%) (P < 0.05), and the latter was also significantly higher than that of euthyroidism (11.9%) (P < 0.05). The positive percentage of IgG2 subclass in sera from patients with hypothyroidism and subclinical hypothyroidism was significantly higher than that of euthyroidism (P < 0.05), the prevalence and positive percentage of IgG4 subclass in sera from patients with hypothyroidism and subclinical hypothyroidism was significantly higher than that of euthyroidism respectively (P < 0.05). The predominant TPOAb IgG subclasses in sera from patients with HT were IgG1 and IgG4. Patients with high levels of TPOAb IgG2, IgG4 subclasses might be at high risk of developing overt hypothyroidism.     

Episodic variations of prolactin, thyroid-stimulating hormone, luteinizing hormone, melatonin and cortisol in infertile women with subclinical hypothyroidism

Preliminary data have suggested that female infertility due to corpus luteum insufficiency may be caused by subclinical hypothyroidism [exaggerated thyroid-stimulating hormone (TSH) response to thyrotrophin- releasing hormone (TRH) stimulation]. L-Thyroxine supplementation has been recommended to achieve pregnancies in subclinical hypothyroid women. This controlled study was carried out in order to investigate the biochemical diagnosis of subclinical hypothyroidism as a possible infertility factor. Five infertile patients (aged 25-36 years) with subclinical hypothyroidism (n = 4, stimulated TSH >20 microU/ml) or primary hypothyroidism (n = 1) and five healthy controls (aged 22-39 years) with normal thyroid function (stimulated TSH <15 microU/ml), regular cycles and no history of infertility were studied in the early follicular phase. In the pre-study evaluation, eight of 23 volunteers (34.8%) had to be excluded because of subclinical hypothyroidism with stimulated TSH values (TSHs) >15 microU/ml. Cycle function of patients and controls was compared by the method of LH pulse pattern analysis. Therefore blood samples were drawn every 10 min during a 24 h period. Sleep was recorded from midnight to 7 a.m. Repetition of the TRH tests at the end of the 24 h blood sampling period confirmed the difference in stimulated TSH values of the two study groups. Pulse analysis for luteinizing hormone (LH), TSH and prolactin showed no differences between patients and controls for pulse frequency, amplitude, height, length, area under curve (AUC) and the 24 h mean. Even the hypothyroid patient had a normal LH pulse pattern. Additional measurement of melatonin in pooled sera every 30 min gave the well-documented diurnal profiles during day and night for both groups. Patients had significantly higher melatonin values at seven time points during the night. Peaks for LH, TSH, prolactin and cortisol were correlated with the sleep stages wake, rapid eye movement, 1 + 2 and 3 + 4. We concluded that corpus luteum insufficiency in female infertility cannot be explained by subclinical hypothyroidism and thus should not be treated with L-thyroxine for fertility reasons.      

Role of fine needle aspiration cytology in thyroiditis

Fine needle aspiration (FNA) of thyroid is a cost-effective, simple, diagnostic tool in the initial screening of patients with thyroid lesions. Its role in a minimally enlarged thyroid in a symptomatic patient suspected of thyroid dysfunction is now well known. It plays an important role in the medical management of all nonpalpable/minimally enlarged thyroid (goiter) in patients suspect for thyroid pathology and/or in combination with thyroid-stimulating hormone, T3 and T4 levels by diagnosing early cases of thyroiditis. FNA may be of assistance in the early detection of subclinical hypothyroidism, which is of utmost importance in pregnant women, and further makes possible the availability of baseline values for future reference. With the implementation of this protocol of FNA thyroid with/without imaging, we affirm that the practice of cytology has differed in different geographic areas and from country to country, depending on economy and availability of infrastructure.     

Establishment of reference intervals for thyroid- stimulating hormone and free thyroxine in amniotic fluid using the Bayer ADVIA Centaur

Thyroid hormone concentrations in amniotic fluid (AF) can aid in the diagnosis of fetal hypothyroidism. However, the availability of reference intervals for thyroid hormones in AF using current methods is limited. The purpose of this study was to validate the Bayer ADVIA Centaur (Bayer Healthcare, Tarrytown, NY) third-generation thyroid-stimulating hormone (TSH), total thyroxine (T4), and free thyroxine (FT4) assays for use with AF and establish reference intervals for these thyroid hormones in AF. Third-trimester AF samples were assayed for TSH, T4, and FT4. Reference intervals were calculated using nonparametric analyses. The reference intervals were as follows: TSH (n = 131), 0.04 to 0.51 microIU/mL (0.04-0.51 mIU/L), with a median of 0.10 microIU/mL (0.10 mIU/L); FT4 (n = 133), less than 0.10 to 0.77 ng/dL (1.29-9.93 pmol/L), with a median of 0.26 ng/dL (3.35 pmol/L). T4 in AF was undetectable using the Centaur assay, reinforcing the importance of validating different manufacturers' immunoassays for use with nonserum specimens. These reference intervals represent the first study performed to date using a third-generation TSH assay and a sensitive FT4 assay.     

The measurement of the serum sex-hormone binding globulin in various thyroid diseases

Synthesis of "sex-hormone binding globulin" (SHBG) is influenced by thyroid hormones and its concentration in the serum of female subjects may be a marker of thyroid hormone effect at the peripheral tissue (liver) level. Compared to the levels found in euthyroid females (n = 46), the mean (+/- S.D.) serum SHBG concentration was found elevated in overt hyperthyroidism (Graves' disease: n = 56; 141.6 +/- 37.6 vs. 48.3 +/- 16.2; toxic nodular goiter: n = 16; 119.9 +/- 50.7 vs. 48.3 +/- 16.2 nmol/l; P less than 0.001). In contrast, it was decreased in manifest hypothyroidism (n = 25; 24.9 +/- 14.8 vs. 48.3 +/- 16.2; P less than 0.001). In the group of preclinical hyperthyroidism (n = 43), despite suppressed TSH secretion, the serum value of SHBG was normal (47.4 +/- 16.8), while its serum level approached the lower border of the normal range in subclinical hypothyroidism (n = 10; 33.6 +/- 6.1 vs 48.3 +/- 16.2 nmol/l; P less than 0.01). Data indicate that the pituitary responds more sensitively than the liver to a slight change of the serum thyroid hormone level. During thyroid hormone replacement for hypothyroidism, measurement of serum SHBG may provide help to assess the response of the target organ to the given therapy. In patients with generalized resistance to thyroid hormone, the serum SHBG level is within the normal range (51.3 +/- 9.8 nmol/l), thus, its determination supports the diagnosis of this disease.     

High levels of circulating chemokine (C-X-C motif) ligand 11 are associated with euthyroid or subclinically hypothyroid autoimmune thyroiditis and with chemokine (C-X-C motif) ligand 10

No data are available for chemokine (C-X-C motif) ligand 11 (CXCL11), together with CXCL10, circulating levels in autoimmune thyroiditis (AT). We measured serum CXCL11 and CXCL10 in 158 patients with newly diagnosed AT (26% with subclinical hypothyroidism), 56 euthyroid controls, and 20 patients with nontoxic multinodular goiter, all similar in gender distribution and age. CXCL11 was significantly higher in patients with AT (113±56 pg/mL) than in controls (67±16 pg/mL) or patients with multinodular goiter (75±18 pg/mL; P<0.0001). Among patients with AT, CXCL11 was significantly higher in those with a hypoechoic ultrasonographic pattern and hypothyroidism. In a multiple linear regression (MLR) model including age, thyroid volume, hypoechogenicity, hypervascularity, thyroid-stimulating hormone (TSH), and anti-thyroid peroxidase, age (P=0.009) and TSH (P<0.008) were significantly related to serum CXCL11. In an MLR model of CXCL11 (ln[pg/mL]) versus age, TSH, CXCL10 (ln[pg/mL]), TSH (P=0.028), and CXCL10 (P=0.003) were significantly and independently related to CXCL11. We first show that circulating CXCL11, together with CXCL10, is increased in patients with thyroiditis and hypothyroidism, and is related to CXCL10 levels. These results underline the importance of a Th1 immune attack in the initiation of AT.     

Impact of hypothyroidism on the development of non-alcoholic fatty liver disease: A 4-year retrospective cohort study

Background/Aims

Hypothyroidism is reported to contribute to the development of nonalcoholic fatty liver disease (NAFLD). We compared the risk of the development of NAFLD among three groups with different thyroid hormonal statuses (control, subclinical hypothyroidism, and overt hypothyroidism) in a 4-year retrospective cohort of Korean subjects.

Methods

Apparently healthy Korean subjects without NAFLD and aged 20-65 years were recruited (n=18,544) at health checkups performed in 2008. Annual health checkups were applied to the cohort for 4 consecutive years until December 2012. Based on their initial serum-free thyroxine (fT4) and thyroid-stimulating hormone (TSH) levels, they were classified into control, subclinical hypothyroidism (TSH >4.2 mIU/L, normal fT4), and overt hypothyroidism (TSH >4.2 mIU/L, fT4 <0.97 ng/dL) groups. NAFLD was diagnosed on the basis of ultrasonography findings.

Results

NAFLD developed in 2,348 of the 18,544 subjects, representing an overall incidence of 12.7%: 12.8%, 11.0%, 12.7% in the control, subclinical hypothyroidism, and overt hypothyroidism groups, respectively. The incidence of NAFLD did not differ significantly with the baseline thyroid hormonal status, even after multivariate adjustment (subclinical hypothyroidism group: hazard ratio [HR]=0.965, 95% confidence interval [CI]=0.814-1.143, P=0.67; overt hypothyroidism group: HR=1.255, 95% CI=0.830-1.899, P=0.28).

Conclusions

Our results suggest that the subclinical and overt types of hypothyroidism are not related to an increased incidence of NAFLD.     

Gestational Age-specific Cut-off Values Are Needed for Diagnosis of Subclinical Hypothyroidism in Early Pregnancy

During the first trimester of pregnancy, thyroid-stimulating hormone (TSH) >2.5 mIU/L has been suggested as the universal criterion for subclinical hypothyroidism. However, TSH levels change continuously during pregnancy, even in the first trimester. Therefore the use of a fixed cut-off value for TSH may result in a different diagnosis rate of subclinical hypothyroidism according to gestational age. The objective of this study was to obtain the normal reference range of TSH during the first trimester in Korean gravida and to determine the diagnosis rate of subclinical hypothyroidism using the fixed cut-off value (TSH >2.5 mIU/L). The study population consisted of pregnant women who were measured for TSH during the first trimester of pregnancy (n=492) and nonpregnant women (n=984). Median concentration of TSH in pregnant women was lower than in non-pregnant women. There was a continuous decrease of median TSH concentration during the first trimester of pregnancy (median TSH concentration: 1.82 mIU/L for 3+0 to 6+6 weeks; 1.53 mIU/L for 7+0 to 7+6 weeks; and 1.05 mIU/L for 8+0 to 13+6 weeks). Using the fixed cut-off value of TSH >2.5 mIU/L, the diagnosis rate of subclinical hypothyroidism decreased significantly according to the gestational age (GA) at TSH (25% in 3+0 to 6+6 weeks, 13% in 7+0 to 7+6 weeks, and 9% for 8+0 to 13+6 weeks, P<0.001), whereas the diagnosis rate was 5% in all GA with the use of a GA-specific cut-off value (P=0.995). Therefore, GA-specific criteria might be more appropriate for the diagnosis of subclinical hypothyroidism.     

Thyroid function in multidrug-resistant tuberculosis patients with or without human immunodeficiency virus (HIV) infection before commencement of MDR-TB drug regimen

BackgroundMycobacterium tuberculosis and human immunodeficiency virus (HIV) are known to cause abnormal thyroid function. There is little information on whether HIV infection aggravates alteration of thyroid function in patients with MDR-TB.ObjectivesThis study was carried out to determine if HIV co-infection alters serum levels of thyroid hormones (T3, T4) and thyroid stimulating hormone (TSH) in patients with MDR-TB patients and to find out the frequency of subclinical thyroid dysfunction before the commencement of MDR-TB therapy.MethodsThis observational and cross-sectional study involved all the newly admitted patients in MDR-TB Referral Centre, University College Hospital, Ibadan, Nigeria between July 2010 and December 2014. Serum levels of thyroid stimulating hormone (TSH), free thyroxine (fT4) and free triiodothyronine (fT3) were determined using ELISA.ResultsEnrolled were 115 patients with MDR-TB, out of which 22 (19.13%) had MDR-TB/HIV co-infection. Sick euthyroid syndrome (SES), subclinical hypothyroidism and subclinical hyperthyroidism were observed in 5 (4.35%), 9 (7.83%) and 2 (1.74%) patients respectively. The median level of TSH was insignificantly higher while the median levels of T3 and T4 were insignificantly lower in patients with MDR-TB/HIV co-infection compared with patients with MDRT-TB only.ConclusionIt could be concluded from this study that patients with MDR-TB/HIV co-infection have a similar thyroid function as patients having MDR-TB without HIV infection before commencement of MDR-TB drug regimen. Also, there is a possibility of subclinical thyroid dysfunction in patients with MDR-TB/HIV co-infection even, before the commencement of MDR-TB therapy.     

Screening for thyroid disorders in a working population

Summary Subclinical thyroid disorders have received increasing attention in recent years due to refined laboratory methods and a stronger emphasis on the role of preventive medicine. We performed a screening for thyroid-stimulating hormone (TSH) on 6884 persons in a working population. In cases in which TSH was not within the normal range we also measured the levels of triiodothyronine (T₃), thyroxine (T₄), and thyroxine-binding globulin (TBG). All persons who did not present with exclusion criteria or other nonthyroidal illnesses (n = 59) and the controls (n = 39) were submitted to thyrotropin-releasing hormone (TRH)-testing. Additionally, sonography of the thyroid was performed on 120 persons (59 subjects with abnormal hormone levels and 61 controls) to determine thyroid size and rule out morphological abnormalities. Based on the TRH test and T₃, T₄, and TBG measurements we found a prevalence of 0.03% (2/6884) for overt hyperthyroidism, 0.33% (23/6884) for subclinical hyperthyroidism, 0.09% (6/6884) for subclinical hypothyroidism, and 0.015% (1/6884) for overt hypothyroidism in the healthy population. In subjects with overt or subclinical hyperthyroidism the prevalence of goiters (thyroid volume > 18 ml in women, > 25 ml in men) was 28%. Of this group 48% had structural abnormalities. All persons with goiters and/or structural abnormalities were over 35 years of age. Among the euthyroid, 20% had thyroid enlargement, and the same proportion presented with structural abnormalities. There were no differences between the two age groups. In the group with overt/subclinical hypothyroidism 47% presented with structural abnormalities of the thyroid; however, none presented with thyroid enlargement. Thyroid nodules were found only in older persons (> > 35 years) with euthyroidism or hypothyroidism. These data confirm the relatively high prevalence of functional and morphological abnormalities of the thyroid. An early substitution with iodine is warranted to prevent functional and morphological disorders of the thyroid in older age. People with subclinical hyperthyroid disorders must avoid exposure to iodine, which can cause an exacerbation of the disease.Abbreviations TBG thyroxine-binding globulin - TRH thyrotropin-releasing hormone - TSH thyroid-stimulating hormone - T₃ triiodothyronine - T₄ thyroxine Dedicated to Prof. Dr. N. Zöllner on the occasion of his 70th birthday     

Possible consequences of subclinical hypothyroidism

Subclinical hypothyroidism is defined as elevated TSH in the presence of normal free T4 and T3 levels. This review discusses the following questions concerning subclinical hypothyroidism that have not been solved yet: 1) does elevated TSH always mean failure of the thyroid gland? 2) Do patients with subclinical hypothyroidism always develop overt hypothyroidism? 3) Are they symptomatic? 4) Does treatment with L-Thyroxine cure these symptoms,--if they exist? Summarizing the results of the literature one can give the following answers: 1) Elevated TSH with normal free T4 can but does not necessarily mean thyroid failure. 2) Patients with positive thyroid antibodies and especially with TSH levels above 10 mU/l are at high risk to develop overt hypothyroidism. 3) Typical symptoms (thyroid-specific, cardiovascular, neurological and psychiatric and finally alterations of risk factors for atherosclerosis) seem to occur in a greatly varying percentage of patients--some of the described symptoms are of questionable clinical importance. 4) Some of the symptoms, especially the cardiovascular, seem to be treatable by L-T4, whereas others like most of the changes in lipid metabolism can not be influenced by normalization of the TSH levels. In conclusion, screening for TSH and free T4 seems to be justified in elderly women, where the prevalence of the disease is approximately 20%. However, treatment of "symptoms" of subclinical hypothyroidism like elevated cholesterol levels or depression should be done only in patients with a TSH > 10 mU/l and there only with great caution in order to avoid unnecessary overdosage with the danger of eliciting atrial fibrillation.     

Thyroglobulin Antibodies are Associated with Symptom Burden in Patients with Hashimoto’s Thyroiditis: A Cross-Sectional Study

Background: Hashimoto’s thyroiditis (HT) is the most common form of autoimmune thyroid disorders characterized by lower production of thyroid hormones and positivity to autoantibodies to thyroglobulin (TgAb) and/or thyroid peroxidase (TPOAb). We performed a comprehensive phenotypic characterization of patients with HT, with specific focus on thyroid autoimmunity, to get better understanding of disease manifestation.

Methods: We collected information on thyroid-specific phenotypes (TSH, T3, T4, fT4, TgAb, TPOAb, thyroid volume) and other clinical phenotypes (age, body surface area, number of hypothyroidism symptoms, blood pressure) from 290 patients with HT without levothyroxine (LT4) therapy with the aim to test for correlations between thyroid-specific and clinical phenotypes.

Results: Our key and novel finding is the existence of significant positive correlation between TgAb levels and the number of symptoms (r = 0.25, p = 0.0001) in HT patients without LT4 therapy that remained significant after adjustment for TPOAb, T3, TSH levels and thyroid volume (β = 0.66, SE = 0.3, p = 0.0299). Increased TgAb levels are significantly associated with fragile hair (p = 0.0043), face edema (p = 0.0061), edema of the eyes (p = 0.0293) and harsh voice (p = 0.0349).

Conclusions: Elevated TgAb levels are associated with symptom burden in HT patients, suggesting a role of thyroid autoimmunity in clinical manifestations of HT. Based on these results, we recommend screening for TgAb antibodies in HT patients with symptom burden. We also suggest that further work on understandings of symptoms appearance due to their autoimmune or hypothyroid causation is needed.     

A high prevalence of thyroglobulin autoantibodies in adults with and without thyroid disease as measured with a sensitive solid-phase immunosorbent radioassay

Sera from 228 patients with thyroid disease and 140 healthy subjects without clinical or biochemical evidence of thyroid disease, were tested using a sensitive solid-phase immunosorbent radioassay (RIA) and a passive hemagglutination test (TRC test) for thyroglobulin antibodies (Tg-ab). With the RIA technique, Tg-ab was found in 27% of the controls (36% of the women and 15% of the men), whereas only 0.7% of them were Tg-ab positive with the TRC test. All individuals with primary hypothyroidism were Tg-ab positive with the RIA, compared with only 56% with the TRC test. Tg-ab (RIA) were found in 43/53 (81%) of the patients with toxic diffuse goiter, and in 30-40% of the patients with toxic nodular goiter, toxic adenoma, atoxic goiter, and thyroid carcinoma, the TRC test being positive in 10-17% of these patients. The high prevalence of Tg-ab in the healthy population suggests that subclinical thyroiditis is more frequent than has been assumed from antibody measurements made with less sensitive methods, and is in agreement with the prevalences reported from autopsy studies.     

妊娠中期妇女甲状腺功能筛查结果分析

目的 探讨妊娠中期妇女甲状腺功能筛查的重要性,为妊娠中期妇女甲状腺疾病的诊疗提供依据.方法 选择277例妊娠中期妇女为妊娠组,162位非妊娠育龄妇女为对照组.采用放射免疫法(RIA)检测FT3、FT4,采用免疫放射法(IRMA)检测TSH.结果 ①妊娠组甲状腺疾病总患病率为14.08％ (39/277),对照组甲状腺疾病总患病率为8.02％(13/162),两组比较差异有统计学意义(P＜0.05).②妊娠组中甲亢(包含亚临床甲亢)患病率为1.44％(4/277),和甲减(包含亚临床甲减)患病率为12.64％(35/277)比较,差异有统计学意义(P＜0.05).对照组甲亢(包含亚临床甲亢)患病率为1.23％(2/162),和甲减(包含亚临床甲减)患病率为6.79％(11/162),差异有统计学意义(P＜0.05).妊娠组甲减(包含亚临床甲减)患病率较对照组升高,差异有统计学意义(P＜0.05).③两组FT3、FT4、TSH结果比较,妊娠组FT4水平低于对照组,差异有统计学意义(P＜0.05);妊娠组TSH水平低于对照组,差异有统计学意义(P ＜0.05);FT3水平无显著差异(P＞0.05).结论 妊娠中期妇女甲状腺疾病患病率增高,以甲减(包含亚临床甲减)居多,对妊娠中期妇女甲状腺功能进行筛查具有重要意义,妊娠期特异性甲状腺激素参考值范围有待明确.     

Thyroid hemiagenesis and elevated thyrotropin levels in a child with Williams syndrome.

A girl with Williams syndrome (WS) presented with elevated thyrotropin (TSH) levels (7.0 microU/ml), normal free thyroid hormone concentrations, and absent antithyroid autoantibodies. Thyroid ultrasonography and scintigraphy showed hemiagenesis of the left lobe and no evidence of ectopic tissue. TSH response to thyrotropin-releasing hormone (TRH) injection (200 microg/mq, i.v.) was exaggerated and prolonged, suggesting subclinical hypothyroidism. The biological activity of circulating TSH was slightly below the normal range [TSH bioactivity (B) to immunoreactivity (I) ratio (TSH B/I) = 0.4, normal: 0.6-2.2]. These abnormalities are similar to those seen in patients with hypothalamic hypothyroidism. Thyroid function is not a recognized manifestation of WS and is not routinely investigated. However, abnormalities of the hypothalamic-pituitary-thyroid (HPT) axis and thyroid dysgenesis have been found in other WS cases. Genes mapping at 7q11.23, contiguous to the chromosomal region deleted in most WS patients, may be involved in the development of the thyroid gland, contributing to the complex phenotype of WS.     

Does Hurthle cell lesion/neoplasm predict malignancy more than follicular lesion/neoplasm on thyroid fine‐needle aspiration?

Thyroid fine-needle aspiration (FNA) is a standard procedure for the clinical triage of thyroid nodules. The diagnosis of an adequately sampled thyroid FNA is generally grouped into three categories: benign, malignant, and indeterminate. The latter group usually includes follicular neoplasm, follicular lesion, and sometimes a more specific diagnosis such as Hurthle cell neoplasm or follicular lesion/neoplasm with Hurthle cell change. Whether a FNA diagnosis of Hurthle cell lesion/neoplasm (HLN) denotes a worse clinical outcome than follicular lesion/neoplasm (FLN) remains controversial. A cohort of 303 thyroid FNA cases with follow-up thyroidectomy in our institutes was identified, with the follow-up excision diagnosis compared to the FNA diagnosis in order to address this issue. Of this cohort, 87 cases had an FNA diagnosis of HLN while 216 cases had a diagnosis of FLN. Upon excision, the FNA diagnosis of HLN group had 14 cases of goiter/nodular hyperplasia (16%), 46 cases of adenoma (12 follicular adenoma (14%) and 34 cases of Hurthle cell adenoma (39%)), and 27 cases of carcinoma (31%, 12 papillary carcinoma and 15 Hurthle cell carcinoma). The FLN group had 74 cases of goiter/nodular hyperplasia (34.3%), 8 cases of Hashimoto thyroiditis (3.7%), 73 cases of follicular adenoma (33.8%), one case of granular cell tumor, and 60 cases of carcinoma (27.8%, 46 papillary carcinoma, 12 follicular carcinoma, and 1 Hurthle cell carcinoma and 1 parathyroid carcinoma) upon excision. There is no significant difference in predicting cancer between the two cytology diagnosis groups (HLN versus FLN, 31% versus 27.8%, P = 0.5771). When sorting all the cases by the surgical diagnosis, while comparable for age at diagnosis, the cancer group having the higher proportion of male patients than the non-cancer group (28.7% versus 16.7%, P = 0.0259). Hurthle cell carcinoma patients are typically older than patients with other cancer diagnoses (59 versus 44, P = 0.0077). Our results suggest that an FNA diagnosis of HLN does not predict more malignancy than FLN. Males and older patients with a HLN FNA diagnosis carry a higher risk of Hurthle cell carcinoma upon thyroidectomy.     

Répercussions biologiques de l'hypothyroïdie fruste

Subclinical hypothyroidism, defined by an isolated increased TSH level, is a frequently encountered condition the clinical outcomes of which are difficult to assess. It's therapeutic management is being discussed. It is essential that biological changes resulting from subclinical hypothyroidism should be known, because they contribute to the prognosis of this condition. Conversion to overt hypothyroidism is not systematic. It is however more likely to occur when the TSH concentration exceeds 10 mUI/l and in patients with thyroid autoimmunity. The impact of subclinical hypothyroidism, as a cardiovascular risk factor seems to be related to lipid abnormalities. An increase in total cholesterol and LDL-cholesterol, reversible with thyroxine treatment, is significant only when the TSH concentration exceeds 10 mUI/l. New biological risk factors — Lp(a), CRP, plasmatic homocysteine — are neither disturbed nor influenced by thyroxine treatment. Other biological abnormalities are less significant and do not contribute to the diagnosis or prognosis of subclinical hypothyroidism.     

甲状腺功能减退与妊娠期血栓前状态的相关分析

目的 探讨甲状腺功能减退对凝血功能的影响,分析甲状腺功能减退与妊娠期血栓前状态的相关性.方法 选取2012年1月至2017年2月我院临床甲状腺功能减退孕妇46例为甲减组,亚临床甲状腺功能减退孕妇39例为亚临床甲减组,随机抽取50例甲状腺功能正常且无合并其他疾病的健康孕妇为对照组,比较3组受试者的甲状腺功能与凝血功能相关指标.结果 与对照组比较,甲减组的促甲状腺激素(TSH)、纤维蛋白(FIB)较高,游离甲状腺素(FT4)、凝血酶原时间(PT)较低,亚临床甲减组TSH较高,PT较低,差异均有统计学意义(P＜0.05).甲减组与亚临床甲减组比较,甲减组FIB较高,差异有统计学意义(P＜0.05).结论 甲状腺功能减退会导致妊娠期血栓前状态,增加患者体内血栓形成的风险,临床上应予重视并给予积极治疗.