The effect of pregnancy on subsequent relapse from Graves' disease after a successful course of antithyroid drug therapy

OBJECTIVE

Pregnancy and the postpartum (PP) period are associated with profound changes of the immune system, which largely influence the clinical activity of autoimmune diseases. The aim of this study was to evaluate the effect of pregnancy and/or the PP period in driving a clinical relapse of hyperthyroidism in patients with Graves' disease (GD) who are in remission after antithyroid drug (ATD) treatment. Data were retrospectively collected from 150 female patients with GD, who were assigned to two groups according to the occurrence of a successful pregnancy after ATD withdrawal.

RESULTS

Relapsing Graves' hyperthyroidism was observed in 70 of 125 patients in group I (no pregnancy after ATD withdrawal) (56.0%) and 21 of 25 patients in group II (pregnancy after ATD withdrawal) (84.0%) (P < 0.05). Logistic regression analysis (dependent variable: relapse/nonrelapse; covariates: age, positive family history for autoimmune thyroid disease, duration of treatment with ATD, number pregnancies at diagnosis, number of pregnancies after ATD withdrawal) showed a significant effect only for the number of pregnancies after ATD withdrawal [4.257 (1.315-13.782)]. The effect was ascribed to the PP period rather than to pregnancy itself because in 20 of 21 patients of group II (95.2%), the relapse of Graves' hyperthyroidism occurred between 4 and 8 months after delivery.

CONCLUSIONS

The PP period is significantly associated with a relapse of hyperthyroidism in GD patients being in remission after ATD. We therefore recommend that patients with GD in remission after a course of ATD should have their thyroid function tested at 3 and 6 months after delivery.

No association between Fas A/G polymorphism and therapeutic effects induced by methimazole treatment for Graves' disease in Northern Chinese

Fas gene, which is related to apoptosis, influences the clinical remission of Graves' disease (GD). This study was performed to determine whether the Fas gene promoter polymorphism at position-670 is associated with different efficacy in GD patients treated with methimazole (MMI). Serum levels of thyroid hormone, sFas and thyrotropic-stimulating hormone receptor antibodies (TRAb) were evaluated as therapeutic efficacy parameters before and after 18-month treatment with MMI in a total of 115 subjects of North China. At the end of the follow-up study, patients were categorized into an effective group (group A) and an ineffective group (group B) according the level of thyroid hormone. Similar to the changes of thyroid hormone, the reductions of sFas and TRAb were significantly different in the two groups (P < 0.05). Meanwhile, we detected that Fas promoter-670 A/G polymorphism existed in the GD patients of North China. We studied the frequencies of genotypes and alleles of the A/G polymorphism in different groups. However, there was no association between different efficacy and Fas promoter polymorphism in patients with GD.

Too early to dismiss Yersinia enterocolitica infection in the aetiology of Graves' disease: evidence from a twin case-control study

BACKGROUND

Yersinia enterocolitica (YE) infection has long been implicated in the pathogenesis of Graves' disease (GD). The association between YE and GD could, however, also be due to common genetic or environmental factors affecting the development of both YE infection and GD. This potential confounding can be minimized by investigation of twin pairs discordant for GD.

AIM

To examine whether YE infection is associated with GD.

DESIGN

We first conducted a classical case-control study of individuals with (61) and without (122) GD, and then a case-control study of twin pairs (36) discordant for GD.

METHODS

Immunoglobulin (Ig)A and IgG antibodies to virulence-associated Yersinia outer membrane proteins (YOPs) were measured.

MAIN OUTCOME MEASURES

The prevalence of YOP IgA and IgG antibodies.

RESULTS

Subjects with GD had a higher prevalence of YOP IgA (49%vs. 34%, P = 0.054) and YPO IgG (51%vs. 35%, P = 0.043) than the external controls. The frequency of chronic YE infection, reflected by the presence of both IgA and IgG YOP antibodies, was also higher among cases than controls (49%vs. 33%, P = 0.042). Similar results were found in twin pairs discordant for GD. In the case-control analysis, individuals with GD had an increased odds ratio (OR) of YE infection: IgA 1.84 (95% CI 0.99-3.45) and IgG 1.90 (95% CI 1.02-3.55). In the co-twin analysis, the twin with GD also had an increased OR of YE infection: IgA 5.5 (95% CI 1.21-24.81) and IgG 5.0 (95% CI 1.10-22.81).

CONCLUSION

The finding of an association between GD and YE in the case-control study and within twin pairs discordant for GD supports the notion that YE infection plays an aetiological role in the occurrence of GD, or vice versa. Future studies should examine the temporal relationship of this association in more depth.

Frequency and characteristics of TBII-seronegative patients in a population with untreated Graves' hyperthyroidism: a prospective study

OBJECTIVE

It is claimed that second generation thyrotropin-binding inhibitory immunoglobulin (TBII) assays have a very high sensitivity for the diagnosis of Graves' hyperthyroidism (GH). However, studies evaluating the accuracy of TBII have been retrospective in nature and/or GH had not been diagnosed independently of TBII. The aim of the present study, therefore, was to prospectively evaluate the frequency and characteristics of TBII-seronegative patients in a population of untreated GH diagnosed independent of serum TBII.

DESIGN

Prospective multicentre observational study.

PATIENTS

A total of 259 consecutive untreated patients with a first episode of GH, diagnosed independent of serum TBII. TBII levels were measured by second generation assay and correlated to thyroid function, clinical characteristics and exposure to environmental factors.

RESULTS

Serum TBII was positive in 245 (94.6%) patients and negative (< 2 IU/l) in 14 (5.4%) patients. TBII-seronegative patients had lower fT4 (median 42.5 vs. 53.9 pmol/l, P = 0.02), T3 (median 3.55 vs. 4.90 nmol/l, P < 0.01) and fT3-index (median 4.30 vs. 6.27, P < 0.01) compared to TBII-seropositive patients. None of the TBII-seronegative patients had TSH-receptor activating mutations, Graves' orbitopathy or pretibial myxedema. Serum TBII was positively correlated to free T3 (fT3)-index and free T4 (fT4)-index (P < 0.01), goitre size (P < 0.01) and the prevalence of Graves' orbitopathy (P < 0.01). There were no significant differences between TBII-seropositive and TBII-seronegative patients in environmental factors.

CONCLUSION

The prevalence of TBII-seronegativity in untreated patients with GH is 5.4% using a second generation assay. TBII-seronegative patients have biochemically less severe thyrotoxicosis and no Graves' orbitopathy. TBII-seronegative and TBII-seropositive patients apparently belong to the same population of GH, albeit the severity of the autoimmune attack is less in TBII-seronegative patients.

The post partum period and the onset of Graves' disease: an overestimated risk factor

OBJECTIVE

Aggravation of autoimmune diseases due to a rebound reaction to the pregnancy-associated immune changes is common during the post partum (PP) period. Previous studies demonstrated that up to 45% of women developing Graves' disease (GD) in the childbearing age had a PP onset of disease. Thus, the PP period was identified as a major risk factor for GD onset.

DESIGN

The aim of this study was to evaluate the role of the PP period as a risk factor for GD occurrence.

METHODS

The reproductive histories of 291 consecutive GD patients (165 patients in the childbearing age and 126 in the non-childbearing age) were retrospectively collected.

RESULTS

The rate of PP onset of GD in all patients with at least one successful pregnancy was 9.8 and 20.0% when only patients in the childbearing age were considered. In the entire cohort of GD women, independent of their age and parity status (i.e., the number of successful pregnancies), the rate of PP onset of GD was 7.2%. The relative frequencies of the rate of PP onset of GD were similar in relation with increasing parity. The rates of false negative (nulliparous) and false positive (parous non-childbearing+childbearing with a non-PP onset of GD) were estimated. The positive predictive value of the PP period for the onset of GD was less than 10%.

CONCLUSIONS

The results of the current study would not support a role for the PP period as a major risk factor for de novo occurrence of GD.

Graves' disease in Saudi Arabia: a ten-year hospital study

OBJECTIVE

To determine clinical manifestation and mode of treatment of Graves' disease at King Khalid University Hospital Riyadh, Saudi Arabia.

METHODS

A retrospective study of all cases of Graves' disease diagnosed at the hospital in the period between January 1995 and December 2004, who received a minimum of two years treatment were included in the study.

RESULTS

A total of 194 patients were seen with female: male ratio of 2.9:1 and mean age of 32 +/- 0.9 years. Sixty nine percent of the patients had positive thyroid antibodies. Palpitations, tremors, weight loss and nervousness were the most common presenting manifestations. Forty nine percent of patients were treated with radioiodine, 38% with antithyroid drugs, and 13% underwent subtotal thyroidectomy.

CONCLUSION

Clinical manifestations of Graves' disease in our patients distinctly differed from those reported in the West and Pacific Islanders with notable rarity of pretibial myxoedema and hyperpigmentation respectively. We also noted higher male to female ratio and an increasing utility of radioactive iodine therapy while use of antithyroid drugs and surgery are declining.

Thyroid nodular disease: an emerging problem

As a consequence of increasing application of ultrasound technology, the detection of asymptomatic thyroid nodules has generally increased. In fact, ultrasound epidemiological studies report that two third of subjects have at least a thyroid nodule, instead of 4-7% detected by clinicians. These evidences suggest the need of a rational approach to the thyroid nodule ''epidemia''. The question of whether clinically unapparent thyroid lesions should be assessed by cytology is still unresolved and, moreover, the clinical significance of nonpalpable (diameter <10 mm) thyroid carcinoma is still a matter of discussion. Aim of this work is to delineate a rational approach to thyroid nodules, taking in account literature data, the most recent guidelines and our clinical experience.

The HLA gene complex in thyroid autoimmunity: from epidemiology to etiology

The autoimmune thyroid diseases (AITD) comprise a cadre of complex diseases whose underlying pathoetiology stems from a genetic-environmental interaction, between susceptibility genes (e.g. CTLA-4, HLA-DR, thyroglobulin) and environmental triggers (e.g. dietary iodine), that orchestrates the initiation of an autoimmune response to thyroid antigens, leading to the onset of disease. Abundant epidemiological data, including family and twin studies, point to a strong genetic influence on the development of AITD. Several AITD susceptibility genes have been identified, with HLA genes, in particular, appearing to be of major importance. Early studies showed association of HLA-DR3 with Graves' disease (GD) in Caucasians. More recently, the importance of an amino acid substitution at position 74 of the DR beta 1 chain of HLA-DR3 (DRb1-Arg74), in susceptibility to Graves' disease, has been shown. Furthermore, there is increasing evidence for a genetic interaction between thyroglobulin variants and DRb1-Arg74 in conferring risk for GD. Mechanistically, the presence of an arginine at position 74 elicits a significant structural change in the peptide binding pocket of HLA-DR, potentially affecting the binding of pathogenic thyroidal peptides. Future therapeutic interventions may attempt to exploit this new bolus of knowledge by endeavoring to block or modulate pathogenic peptide presentation by HLA-DR.

Association and linkage studies of the 20q11.2 region (GRD-2 locus) with Graves' disease in the Tunisian population

OBJECTIVE

A genome-wide screen has shown linkage to the GRD-2 locus in Graves' disease (GD). Furthermore, a positional candidate gene maps to this locus; the CD40 gene has been reported to be associated and may predispose to the disease. The aim of this study was to replicate/reject the GRD-2 and to determine if the single nucleotide polymorphism (SNP) of the CD40 (CD40 C/T-1) confers susceptibility to GD.

METHODS

The present study examined a dataset of 11 families with GD using 10 microsatellite markers and a case-control study consisting of 76 sporadic GD patients and 66 healthy subjects to determine the implication of the GRD-2. Both non-parametric linkage and association tests were performed. Genotyping of the CD40 C/T-1 was carried out using a polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP).

RESULTS

The intrafamilial association and the case-control study showed no association between CD40 C/T-1 and GD. In addition, a high percentage of the C allele (96.9%) of CD40 SNP among control data was observed. The linkage analyses showed that the highest non-parametric LOD score was 1.67 at the D20S119 marker and the maximum attainable LOD score was 1.66. This result provides interesting evidence for linkage between GRD-2 and GD.

CONCLUSION

The CD40 gene seems to be not associated with GD in the Tunisian population, whereas the GRD-2 locus could harbour other candidate gene(s) to the genetic susceptibility of GD.

[Epidemiology of thyroid tumors: effect of environmental iodine intake]

The incidence of thyroid cancer has been reported to be 0.5-1.3%, when assessed by sonographic examination and 3.7-28.4% by histologic examination at autopsies. These incidences are much higher than those of clinically evident thyroid cancer, which are 2.0/100,000 for males and 7.2/100,000 for females, reported in Japan. In iodine deficient areas, chronic stimulation by TSH causes multinodular autonomous growth and function, leading to hyperthyroidism in middle-aged and elderly subjects. Incidence of Plummer's disease among Japanese with sufficient iodine intake is very low, accounting for 0.5-0.8% of all thyroid nodules and 0.3% of all thyrotoxic patients. The Plummer/Graves ratio was higher than 1 in endemic goiter area before iodine supplementation. Iodine intake affects the type of thyroid carcinoma. Decreased intake of iodine is associated with higher frequency of follicular and anaplastic cancers and lower frequency of papillary cancer. The high prevalence of papillary cancer(>85%) with good prognosis may explain the preferred selection of partial rather than total thyroidectomy in Japan.

Hepatitis B vaccine and risk of autoimmune thyroid disease: a Vaccine Safety Datalink study

PURPOSE

Hepatitis B vaccine has been postulated as a possible cause of autoimmune disorders, including autoimmune thyroid diseases (ATD). Cases of Graves' disease and Hashimoto's thyroiditis, following hepatitis B vaccine have been reported to the Vaccine Adverse Events Reporting System (VAERS). To test the hypothesis that hepatitis B vaccine increases the risk of ATD, we conducted a case-control study, within the Vaccine Safety Datalink project.

METHODS

We identified potential cases of Graves' disease and Hashimoto's thyroiditis, among persons aged 18-69 years from administrative data recorded by three health maintenance organizations (HMOs) and verified cases by medical record review. Controls were frequency-matched to cases by birth year, sex, and study site. Vaccine information was collected from administrative records, chart review, and telephone interviews with study subjects. We enrolled 355 Graves' disease cases, 418 Hashimoto's thyroiditis cases, and 1102 controls. We assessed the association between ever-receipt of hepatitis B vaccine, as well as receipt of hepatitis B vaccine less than 1 year, 1-5 years and at least 5 years prior to the index date, and the risk of ATD.

RESULTS

Ever-receipt of hepatitis B vaccine was not associated with risk of Graves' disease (odds ratio (OR), 0.90; 95% confidence interval (CI), 0.62-1.32) or Hashimoto's thyroiditis (OR, 1.23; 95%CI, 0.87-1.73). There was also no association between the time interval since receipt of hepatitis B vaccination and either outcome.

CONCLUSIONS

We did not observe an increased risk of Graves' disease or Hashimoto's thyroiditis, following receipt of hepatitis B vaccine.

TSH-receptor antibodies determined by the first, second and third generation assays and thyroid-stimulating antibody in pregnant patients with Graves' disease

The measurement of TSH receptor antibody (TRAb) has been recommended to predict the risk of neonatal hyperthyroidism (NH) in pregnant women with Graves' disease (GD). For the first generation TRAb (TRAb1) assay with commercial kit (Brahms, Berlin, Germany; or Cosmic co., Tokyo, Japan) an arbitrary limit of 40 U/l or 50% was suggested to indicate risk when measured late in pregnancy. In order to substitute TRAb1 with the second generation TRAb using porcine TSH receptor (pTRAb2) and human recombinant TSH receptor (hTRAb2) and the third generation TRAb (TRAb3) assay for this purpose, we measured TRAb in these four methods late in pregnancy in a total of 62 pregnant women with Graves' disease. The data showed that no cases with TRAb1 >50% has been missed if the TRAb1 assay was replaced by the pTRAb2, hTRAb2 or TRAb3 assay using their equivalent cut-off value of 70%, 10 IU/l, and 75%, respectively, but that an additional group of women would have been included in the risk group, especially in the TRAb3 assay. Next, the effect of maternal TRAb on thyroid function of offspring was studied in the 47 pregnant women with GD (43 with TRAb1 <50% and 4 with TRAb1 >50% during late pregnancy). In 2 women who gave birth to hyperthyroid children at days 6 and 14 of life, the maternal sera had strongly positive levels of TRAb1 (73.5% and 84.1%), pTRAb2 (84.9% and 91.5%), hTRAb2 (40.68 IU/L and 89.70 IU/L) and TRAb3 (92.1% and 93.5%) late in pregnancy, with one case displaying high positive (1114.3%) thyroid stimulating antibody (TSAb) level and the other case had moderate positive (433%) TSAb level. Of the remaining 45 women, 43 had TRAb1 <50% and the other 2 had TRAb >50% including 1 with low TSAb positive and 1 with positive thyroid stimulating blocking antibody (TSBAb) and negative TSAb; all of them gave birth to euthyroid children. Finally, a serial study regarding TRAb in 23 women with Graves' disease during pregnancy showed that TRAb1, pTRAb2, hTRAb2, TRAb3 value and TSAb level decreased significantly as pregnancy progressed. In conclusion, the present study supported TRAb as a useful marker to predict the risk of NH.

The incidence of gestational hyperthyroidism and postpartum thyroiditis in treated patients with Graves' disease

Graves' disease (GD) is one of the most common thyroid diseases that cause hyperthyroidism. Gestational transient thyrotoxicosis (GTT) is nonautoimmune hyperthyroidism that occurs in women with a normal pregnancy. Postpartum transient thyroiditis (PTT) is a destructive thyroiditis induced by autoimmune mechanism in the postpartum period. Hyperthyroidism due to GD usually tends to improve during the course of gestation and exacerbate after delivery. When the patient with treated GD presents with thyrotoxicosis in the early pregnancy or in the postpartum period, differential diagnosis of exacerbation of GD with GTT or PTT is important because the latter disorders are fundamentally transient. To evaluate the incidence of GTT and PTT in a GD population, we investigated the thyroid functions, thyrotropin receptor antibodies (TRAb), and human chorionic gonadotropin (hCG) during pregnancy and for 1 year after delivery for 39 pregnancies in 34 women with GD. The incidence of GTT was 26% (10/39) of pregnancies. The peak value of hCG in the GTT group ([23.7 +/- 14.5] x 10(4) IU/mL, n = 9) was significantly higher than that in the non-GTT group ([13.3 +/- 4.7] x 10(4) IU/mL, n = 19). The incidence of PTT was 44% (17/39) of deliveries. The free triiodothyronine (FT(3))/free thyroxine (FT(4)) ratio of the exacerbation group of GD (3.1 +/- 1.0, n = 10) at the time of thyrotoxicosis after delivery was significantly higher than that of the PTT group (2.5 +/- 0.4, n = 16). The peak TRAb value of the exacerbation group of GD (72.5 +/- 121.7 IU/L, n = 10) at the time of thyrotoxicosis after delivery was also significantly higher than that of the PTT group (1.4 +/- 0.8 IU/L, n = 16). In conclusion, the high peak value of hCG is valuable for suspecting GTT, and the high FT(3)/FT(4) ratio is valuable for suspecting recurrence in the patients with GD. In both situations, changes of TRAb were also valuable in differentiating the recurrence of GD from GTT or PTT.

[Hyperthyroidism in children. Experience in internal medicine in Mali]

INTRODUCTION

Thyroid pathology is frequent in Mali, which is an endemic zone for goiter. But this pathology rarely occurs in children. The purpose of our study was to characterize this illness among children in Mali.

METHODS

We report on patients aged less than 15-year old who presented with clinical signs and symptoms with hyperthyroidism at the medicine service at Hospital de Point G from January 1999 and December 2005 to determine the characteristics of hyperthyroidism.

RESULTS

The frequency was 9.6 per thousand (38/3972), with an average age of 12.5+/-3.34-year. The sex ratio was 3 girls/1 boys. The most common symptoms were tachycardia (n=30, 78.9%), palpitations (n=15, 34.4%). 31 patients (81.5%) presented with exophthalmoses, 93.5% being bilateral. Weight loss was present in 31.5% (n=12). Goiter was present in 37 patients (97.4%). The goiter was diffuse in 27 patients (73%) and nodular in 10 (27.%). The presence of goiter caused signs of compression in the neck in half of the cases: dyspnea and dysphonia were the most common consequences. TSH less than 0.05 microUI/1 was used to confirm the diagnosis. Graves's disease was the most common cause (n=32, 84.2%), followed by toxic adenoma (n=4, 10.5%). Other causes included toxic multinodular goiter and thyroiditis. Etiologies were independent of sex and age: (p=0.95). All patients were started on medical therapy upon diagnosis. 7 patients (18.4%) were lost to follow-up during the 6 months of treatment. Remission was obtained in 26 patients (83.9%), and relapse occurred in 5 patients (16.1%).

CONCLUSION

The frequency of hyperthyroidism in children in Mali is a problem in a goiter endemic zone like Mali. Poor general health in children and signs and symptoms of neck compression are markers of progressive disease.

Seasonality of month of birth of patients with Graves' and Hashimoto's diseases differ from that in the general population

OBJECTIVE

We aimed to test the viral hypothesis in the pathogenesis of autoimmune thyroid disease (AITD).

DESIGN

We determined the pattern of month of birth (MOB) distribution in patients with AITD and in the general population and searched for differences between them.

METHODS

A total of 1023 patients were included in this study; 359 patients had Graves' hyperthyroidism (GrH) and 664 had Hashimoto's hypothyroidism (HH). We divided the patients with HH into three subgroups according to their thyroid peroxidase (TPO) antibody titers at diagnosis: low levels (<500 IU/ml), high levels (500-1000 IU/ml), and extremely high levels (>1000 IU/ml). We used cosinor analysis to analyze the data.

RESULTS

Overall, patients with GrH and HH had a different pattern of MOB distribution when compared with the general population and between groups. Furthermore, among both patients with GrH and HH, both genders had a different pattern of MOB distribution when compared with the general population and this pattern was also different between genders. Finally, only women with extremely high titers of TPO antibodies at diagnosis and men with low or extremely high TPO antibody levels showed rhythmicity in MOB, with a pattern of MOB distribution different from that in controls.

CONCLUSIONS

The different MOB seasonality in both GrH and HH points towards a similar maybe even common etiology with type 1 diabetes mellitus and multiple sclerosis, namely a seasonal viral infection as the initial trigger in the perinatal period, the clinical disease resulting from further specific damage over time.

Prevalence and functional significance of antipituitary antibodies in patients with autoimmune and non-autoimmune thyroid diseases

BACKGROUND

Circulating antipituitary antibodies (APA) are markers of autoimmune hypophysitis, which may cause deficient pituitary function. The prevalence of APA in autoimmune thyroid disorders (AITD) is uncertain.

OBJECTIVES

The aims of this study were 1) to evaluate APA prevalence in a large series of patients with AITD and non-AITD and 2) to investigate the functional significance of APA by assessing pituitary function in APA-positive patients.

DESIGN AND SETTING

We conducted a health survey on consecutive AITD and non-AITD patients at a tertiary referral center (Department of Endocrinology, Pisa).

PATIENTS

Subjects, including 1290 consecutive patients with thyroid disorders (961 AITD and 329 non-AITD) and 135 controls, were enrolled in the study.

METHODS

APA (indirect immunofluorescence), free T(4), free T(3), TSH, and organ-specific autoantibodies were assayed in all patients. Functional pituitary evaluation was performed in most APA-positive patients.

RESULTS

APA frequency was higher in AITD (11.4%) than in non-AITD (0.9%; P < 0.0001) patients; all control subjects had negative APA tests. APA were more frequently found in Hashimoto's thyroiditis (13%) than in Graves' disease (7.1%; P = 0.05). Of 110 APA-positive AITD patients, 20 (18.2%) had autoimmune polyglandular syndrome, whereas 90 (81.8%) had apparently isolated AITD. APA positivity increased percentage of autoimmune polyglandular syndrome in our series from 10.4 to 13.5%. Of 110 APA-positive patients, 102 were submitted to dynamic testing for functional pituitary assessment; 36 patients (35.2%) had mild or severe GH deficiency (GHD). No additional anterior pituitary hormone deficiencies were found; one patient had central diabetes insipidus. Pituitary abnormalities at magnetic resonance imaging were found in most APA-positive GHD patients.

CONCLUSIONS

APA are frequently present in patients with AITD. Patients should be tested for APA because positive tests are associated with GHD.

Clinical and subclinical autoimmune thyroid disorders in systemic sclerosis

OBJECTIVE

Several studies have reported the association of systemic sclerosis (SSc) with thyroid autoimmune disorders, but most of them have neither an appropriate control group nor include a complete thyroid work-up.

DESIGN

The aim of our study was to evaluate the prevalence of thyroid disorders in a large number of patients with SSc using a complete clinical evaluation.

METHODS

Thyroid-stimulating hormone (TSH), free triiodothyronine, free thyroxine, antithyroglobulin and antithyroid-peroxidase (AbTPO) autoantibodies, thyroid ultrasonography and blood flow and fine needle aspiration were performed in 202 SSc patients versus 404 gender- and age-matched controls from the general population, with similar iodine intake, to evaluate the prevalence of clinical and subclinical thyroid disorders.

RESULTS

Odds ratio (OR) for female SSc versus controls was: for subclinical hypothyroidism, 3.2 (95% CI)=1.8-5.7); for clinical hypothyroidism, 14.5 (95% CI=2.3-90.9); for AbTPO positivity, 2.7 (95% CI=1.8-4.1); for hypoechoic pattern, 3.2 (95% CI=2.2-4.7); for thyroid autoimmunity, 3.7 (95% CI=2.6-5.4); for thyroid volume <6 ml, 1.8 (95% CI=1.2-2.7). OR for thyroid autoimmunity in male SSc versus controls was 10.8 (95% CI=2.2-52.4). Mean values of TSH in female SSc, and of AbTPO in female and male SSc were higher (P<0.01) than in controls. We observed three cases of Graves' disease in female SSc versus zero in controls (P=0.0140), and two cases of papillary thyroid cancer in SSc patients.

CONCLUSIONS

Thyroid function, AbTPO and ultrasonography should be tested as part of the clinical profile in SSc patients. Females, subjects with positive AbTPO and hypoechoic and small thyroid should have thyroid function follow-up and appropriate treatment in due course.

TSH receptor antibodies in subjects with type 1 diabetes mellitus

The research was undertaken to study the prevalence of TSH receptor antibody positivity in patients with type 1 diabetes. A total of 74 subjects with type 1 diabetes were enrolled in this cross-sectional study. Thyroid function test and assessment of thyroid autoimmunity with anti-TPO and TSH receptor antibody were done in all patients. A total of 33 males and 41 females with type 1 diabetes were studied. The prevalence of TSH receptor antibody positivity alone was 18%. The prevalence of thyroid autoimmunity with anti-TPO as a marker was 28%; the prevalence increased to 43% when TSH receptor antibody was also measured. Majority of the subjects with antithyroid antibody positivity were also positive for GAD65 antibodies. As a significant proportion of type 1 diabetic subjects have positivity to TSH receptor antibody, we suggest that larger studies should be conducted to study the benefits of TSH receptor antibody-based screening for thyroid dysfunction in type 1 diabetic subjects. As the TSH receptor antibodies could be of the stimulating or of the blocking type, subjects with antibody positivity could be at risk of developing hyperthyroidism or hypothyroidism.

[Thyroid diseases in sub-Saharan Africa]

Thyroid gland diseases vary according to the environment. In sub-Saharan Africa, they are also influenced by population isolation and the absence of food self-sufficiency, both factors affecting the onset and persistence of iodine-deficiency goiters. More cosmopolitan diseases are now added to these thyroid disorders. Women are mainly affected (94.2%), most often with euthyroid goiters (54.7%), followed by Graves disease (13.1%), hypothyroidism (8.8%), thyroiditis (6.6%), toxic multinodular goiters (6.6 %) and unclassified goiters (10%) [Gabon]. The paucity of laboratories specializing in endocrinology and of nuclear medicine facilities, the delay in diagnosis that results in compressive or recurrent goiters, and endemic goiters are all typical in Africa. In children and adolescents, death rates increase with congenital or acquired thyroiditis as with delayed physical or mental development. In this environment, thyroiditis can also be pregnancy-related. Very recent surveys show a prevalence of endemic goiters of 28.6% in the community of Sekota, Ethiopia, 64-70% in Sahel-Sudan (population aged 10-20 years), 20-29% in KwaZulu-Natal (school children), 14.3-30.2% in Namibia (school children), 0.21% (congenital hypothyroidism or cretinism) in Plateau State, Nigeria, 55.2% at Zitenga, Burkina Faso (210 persons 0-45 years), and 10% in Hararé and Wedza, Zimbabwe (newborn TSH >10.1 microIU/mL). The prevalence of goiters is 43.6% in children emigrating from Ethiopia to Israel. Millet from semi-arid zones contains apigenin at a concentration of 150 mg/kg and luteolin at 350 mg/kg, both of which can interfere with thyroid function. The harmful effects of cassava (also known as manioc) are better known: milling cassava reduces its goitrogenic potential. In addition to iodine deficiency, selenium deficiency, and the effect of the thiocyanates in cassava, ion concentrations in soil and drinking water appear to play a role. The proportion of thyroid surgery indicated for hyperthyroidism has tripled, now accounting for 18.5% of all such operations. This disorder is found today in subjects older than 50 years, mainly from rural areas, and caused most often by Graves disease (25 of 51 cases). Graves disease in young women can cause serious problems during pregnancy; in such cases assessment of the minimal effective dose of antithyroid agents is essential. Carbimazole leads to remission in 61% of cases of Graves disease. Hypothyroidism can be auto-immune and often in patent forms because of insufficient screening in Africa: 24 cases in Dakar (1984) and 37 others noticed by us (1998). Single-nodule tumors were assessed in 89 patients in Khartoum: they were found to be simple goiters in 72% of cases, follicular adenoma in 13.5%, cancer in 13.5% (with 6 of the 12 cases follicular, 5 papillary, and 1 anaplastic). The sex ratio for thyroid cancer in Ouagadougou is 0.22, thus mainly women. It affects mainly women in their 30s. Thyroid cancer at Ibadan was found to be papillary carcinoma in 45.3% of cases; follicular forms were seen in 44.5% and this series includes 5% of medullary cancers (7 cases), with a mean age of 34 years. Already 4 other cases from Francophone sub-Saharan Africa have been noticed. Iodine deficiency is suggested to play a role because follicular cancer in southern Africa accounts for up to 55% of thyroid cancers. Thyroid cancers in Algeria are associated with low socioeconomic status and characterized by a high prevalence of cancers discovered at an advanced stage and of anaplastic carcinomas. Oral potassium iodate is recommended: 30 mg of iodate a month or 8 mg every two weeks. Iodized oil has been recommended by some authors, as well as a combination of iodine and sugar, and the iodation of drinking water; these are in addition to the proposed methods of opening up areas by new infrastructure). In conclusion, thyroid disease is due predominantly to iodine deficiency and goitrogenic products, but we also note the increasing emergence of hyperthyroidism, especially Graves disease, atrophic auto-immune hypothyroidism, and thyroid cancer. The insufficiency of infrastructure in transportation, endocrinology, and nuclear medicine are a public health challenge for the third millennium.

beta-2-adrenergic receptor gene polymorphism confers susceptibility to Graves disease

Graves disease (GD) is an autoimmune disorder with genetic predisposition. The polymorphisms 47A-->G (Arg16Gly) and 79C-->G (Gln27Glu) of the adrenergic beta-2 receptor (ADRB2) gene in the 5q32 region affect the functional reaction to adrenergic stimulation, which contributes to the regulation of immunological response. The -367T-->C polymorphism within the 5'-leading regulatory sequence affects ADRB2 transcriptional activity. The aim of the present study was to investigate whether ADRB2 gene variants are associated with susceptibility to GD. All polymorphisms were studied in Polish GD patients (n=300) and healthy control subjects without a family history of autoimmune disorders (n=301). Genotypes were determined by the MassARRAY system (Sequenom, San Diego, CA). Gly16 and Gln27 allele frequencies were 61.4% and 55.2% among healthy controls, almost the same as previously reported in 4441 white participants of a cardiovascular health study. We found a higher risk of GD in Gln27 carriers (CC or CG genotypes) than in Glu27 homozygous (GG genotype) participants (OR=1.99, 95% CI: 1.27-3.12, p=0.003, pcorr=0.03). The frequency of the 79GG protective genotype was significantly smaller in the GD patients without symptoms of Graves ophthalmopathy compared to controls (10% vs 22%, OR=0.41, 95% CI: 0.234-0.706, p=0.0017, pcorr=0.015). We didn't find any association of -367T--> or 47A-->G genotypes/alleles with Graves disease, however, haplotype analysis has shown a significant difference in haplotype distribution between patients and controls (the global p=0.001) with increased -367T/47A/79C haplotype frequency in GD patients compared to controls (34% vs 25%, p=0.00073, pcorr=0.0044). In conclusion, Gln27 carriers (79CC or 79GC genotypes) have increased risk of Graves disease. Our results suggest that ADRB2 plays a role in susceptibility to Graves disease in humans.

Mood and thyroid immunity assessed by ultrasonographic imaging in a primary health care

BACKGROUND

Psychiatric morbidity is highly prevalent in the primary health care settings and it may be related to autoimmune thyroid disease (AITD). The aim of this study was to evaluate the impact of thyroid immunity, evident by hypo-echoic thyroid ultrasound pattern, on prevalence of depression and anxiety in a primary care setting.

METHODS

In a cross-sectional design, 504 consecutive primary care patients were invited to the study and 474 patients completed the study. They were screened for depression and anxiety using the Hospital Anxiety and Depression Scale (HADS), were interviewed for affective disorders using the Mini International Neuropsychiatric Interview, and were evaluated by ultrasonographic imagining of the thyroid gland.

RESULTS

Among patients with hypo-echoic thyroid (n=122) prevailed women and those patients were older than patients with normo-echoic thyroid (n=352). Women, but not men, with hypo-echoic thyroid compared to those with normo-echoic thyroid had higher scores on the anxiety subscale of the HADS (p=0.03). Among women with hypo-echoic thyroid, only those pre-menopause, but not those post-menopause, had greater prevalence of high scores on the depression subscale of the HADS (p=0.02) and a greater likelihood of using psychiatric medications (p=0.001).

LIMITATIONS

Lack of cytological evaluation of the thyroid gland; lack of serum thyroid antibodies concentrations; and lack of thyroid hormone concentrations.

CONCLUSIONS

Thyroid immunity is related to mood symptoms in primary care patients. These effects are gender specific and in women, they are most evident before menopause.

[Toxic nodular goiter]

INTRODUCTION

To date no study in our country was specifically dedicated on toxic nodular goiter. They were just mentioned in generally studies about hyperthyroidism.

METHOD

The authors report a retrospective series of 62 cases of toxic nodular goitre collected between 1979 and 1999 at the internal medical clinic of Dakar teaching hospital. The diagnostic of toxic nodule was retained on following criteria: to existence of one or several thyroid nodule with signs or thyrotoxicosis, the existence of a hyperfixating nodule at 131 iodine scintigraphy. Increasing of T3 and/or T4 thyroide hormone. The aims of the study was to analyse the epidemiological, clinical, and therapeutics aspects.

RESULTS

We are collected 49 cases of solitary nodule (79.03%) and 13 cases of multi nodular goitre (20.97%). In the cases of solitary nodule, mean age was 40 years, sex ratio of 0.04 (47 female, 2 men). The nodule was clinically diagnosed in 47 cases (95.9%) and extinctive in 73.5%. 34.3% of patients have cardiothyreosis. In the cases of multi nodular goitre mean age was 45 years, all cases were female, goitre was clinically identified in 95.3% (12 patients) and 46.5% had cardiothyreosis. 62% of patients were lost to follow up during medical treatment. Only 2 patients on the 37 who were addressed for surgery come back after thyroidectomy.

CONCLUSION

This study confirm the predominance of toxic nodular goitre in young female, its severity related to cardiothyreosis and underlines the difficulties limited to the therapeutical care.

Pattern of thyroid disorders in the southwestern region of Nigeria

OBJECTIVE

Thyroid disorders were thought to be rare in Africans in the early 1960s. However the 1970s witnessed an upsurge in reported cases of thyroid disorders in Africans. In endocrinology clinics in Nigeria, thyroid disorders are the second most common endocrine disorders seen. This study attempts to describe the patterns of thyroid disorders, clinical features, and complications as seen in Nigerians.

DESIGN/SUBJECTS

This is a descriptive study that took place from June 2004 to August 2005 in the Department of Medicine of the Lagos State University Teaching Hospital, Ikeja, Nigeria. The demographic data, anthropometric indices, clinical features and associated complications of thyroid disorders were documented. Patients were categorized into three broad groups according to symptoms and biochemical profile as being euthyroid, thyrotoxic and hypothyroid.

RESULTS

The total number of patients with thyroid disorders seen in a 15-month period was 78. The female:male ratio was 5:1. The mean (standard deviation) age of all the subjects studied was 40 (12.4) years. The female:male ratio of those with thyrotoxicosis was 5.6:1. Cardiovascular complications of thyrotoxicosis, namely heart failure and atrial fibrillation, were the most common reasons for prolonged morbidity and hospitalizations. Hypothyroidism was present in five (7%), Graves disease/hyperthyroidism in 63 (84%), and euthyroid in 10 (9%). Obstructive symptoms were documented in eight (13%) of the subjects with palpable goiters.

CONCLUSION

Thyroid disorders in Nigerians are a significant cause of cardiovascular morbidity. Public awareness of thyroid disorders and their potential complications could lead to improved diagnostic and therapeutic facilities.