Thyroid autoantibody profiles in ophthalmic dominant and thyroid dominant Graves' disease differ and suggest ophthalmopathy is a multiantigenic disease

Seminoma-associated orbitopathy mimicking thyroid-associated orbitopathy: report of a case and literature review

The authors describe a case of bilateral diffuse paraneoplastic orbital myositis induced by a stage IA left testicular pure seminoma. The patient presented with findings typical of thyroid-associated orbitopathy (TAO) and was thought to have TAO until discovery of the malignancy. Treatment included an urgent orchiectomy, as well as 7 weeks of therapeutic plasma exchange. This is the fifth reported case of seminoma-associated orbitopathy, and the second to occur while cancer was in the occult phase. Although seminoma-associated orbitopathy is exceedingly rare, it can masquerade as TAO and should be considered in the differential diagnosis of any young male with atypical TAO findings.

Thyroid stimulating immunoglobulin concentration is associated with disease activity and predicts response to treatment with intravenous methylprednisolone in patients with Graves' orbitopathy

Background

Thyroid stimulating immunoglobulins (TSI) play a central role in the pathogenesis of Graves' orbitopathy (GO), while soluble interleukin-2 receptor (sIL-2R) is a marker for T-cell activity. We investigated TSI and sIL-2R levels in relation to thyroid function, disease activity and severity and response to treatment with intravenous methylprednisolone (IVMP) in patients with GO.

Methods

TSI (bridge-based TSI binding assay), sIL-2R, TSH and fT4 levels were measured in biobank serum samples from 111 GO patients (37 male, 74 female; mean age 49.2 years old) and 25 healthy controls (5 male, 20 female; mean age 39.8 years old). Clinical characteristics and response to treatment were retrospectively retrieved from patient files.

Results

Higher sIL-2R levels were observed in GO patients compared to controls (p < 0.001). sIL-2R correlated with fT4 (r = 0.26), TSH (r = -0.40) and TSI (r = 0.21). TSI and sIL-2R concentrations were higher in patients with active compared to inactive GO (p < 0.001 and p < 0.05, respectively). Both TSI and sIL-2R correlated with total clinical activity score (CAS; r = 0.33 and r = 0.28, respectively) and with several individual CAS items. Cut-off levels for predicting active GO were 2.62 IU/L for TSI (AUC = 0.71, sensitivity 69%, specificity 69%) and 428 IU/mL for sIL-2R (AUC = 0.64, sensitivity 62%, specificity 62%). In multivariate testing higher TSI (p < 0.01), higher age (p < 0.001) and longer disease duration (p < 0.01) were associated with disease activity. TSI levels were higher in patients with a poor IVMP response (p = 0.048), while sIL-2R levels did not differ between responders and non-responders. TSI cut-off for predicting IVMP response was 19.4 IU/L (AUC = 0.69, sensitivity 50%, specificity 91%). In multivariate analysis TSI was the only independent predictor of response to IVMP (p < 0.05).

Conclusions

High TSI levels are associated with active disease (cut-off 2.62 IU/L) and predict poor response to IVMP treatment (cut-off 19.4 IU/L) in GO. While sIL-2R correlates with disease activity, it is also related to thyroid function, making it less useful as an additional biomarker in GO.

Dysthyroid Optic Neuropathy

PURPOSE

Dysthyroid optic neuropathy (DON) is a sight-threatening complication of thyroid eye disease (TED). This review provides an overview of the epidemiology, pathogenesis, diagnosis, and current therapeutic options for DON.

METHODS

A literature review.

RESULTS

DON occurs in about 5% to 8% of TED patients. Compression of the optic nerve at the apex is the most widely accepted pathogenic mechanism. Excessive stretching of the nerve might play a role in a minority of cases. Increasing age, male gender, smoking, and diabetes mellitus have been identified as risk factors. Diagnosis of DON is based on a combination of ≥2 clinical findings, including decreased visual acuity, decreased color vision, relative afferent pupillary defect, visual field defects, or optic disc edema. Orbital imaging supports the diagnosis by confirming apical crowding or optic nerve stretching. DON should be promptly treated with high-dose intravenous glucocorticoids. Decompression surgery should be performed, but the response is incomplete. Radiotherapy might play a role in the prevention of DON development and may delay or avoid the need for surgery. The advent of new biologic-targeted agents provides an exciting new array of therapeutic options, though more research is needed to clarify the role of these medications in the management of DON.

CONCLUSIONS

Even with appropriate management, DON can result in irreversible loss of visual function. Prompt diagnosis and management are pivotal and require a multidisciplinary approach. Methylprednisolone infusions still represent first-line therapy, and surgical decompression is performed in cases of treatment failure. Biologics may play a role in the future.

The phenotype of Graves' orbitopathy is associated with thyrotropin receptor antibody levels

PURPOSE

Graves' orbitopathy (GO) is a specific inflammatory disorder of the orbit characterized by a highly heterogeneous clinical phenotype. The role of thyrotropin receptor antibodies (TSH-R-Ab) has been widely researched, however there is still no evidence that these antibodies have a direct pathogenic role in this pathology. The aim of this study was to examine their relation to the individual clinical features of GO.

METHODS

Ninety-one consecutive patients with GO were recruited. Total antibody concentration (TSH-R binding inhibitory immunoglobulins, TBII) and their functional activity (stimulating TSH-R-Ab, TSAb) were measured using binding immunoassay and cell-based bioassay, respectively.

RESULTS

Both TSAb and TBII levels were significantly associated to the clinical parameters of GO activity. TSAb was a more sensitive serological marker compared to TBII pertaining to eyelid retraction and edema, proptosis, extra-orbital muscle disorders, diplopia, irritable eye symptoms, and photophobia. TSAb, but not TBII, was a significant predictive marker of conjunctival redness, chemosis, caruncle/plica inflammation, eye irritation, and orbital pain, (odds ratio: 3.096, p = 0.016; 5.833, p = 0.009; 6.443, p = 0.020; 3.167, p = 0.045; 2.893, p = 0.032; versus 2.187, p = 0.093; 2.775, p = 0.081; 3.824, p = 0.055; 0.952, p = 0.930; 2.226, p = 0.099, respectively). Neither TSAb nor TBII correlated with the level of proptosis (ρ = 0.259, p = 0.090, and ρ = 0.254, p = 0.104, respectively), however rising TSAb levels were strongly associated to the level of proptosis.

CONCLUSIONS

TSH-R-Ab were significantly associated with GO's phenotype. Especially TSAb, as a sensitive and predictive serological biomarker, can improve diagnosis and management of GO.

Comparison Between Thyroid Stimulating Immunoglobulin and TSH-Receptor Antibodies in the Management of Graves' Orbitopathy

OBJECTIVES

TSH-receptor antibodies (TRAb) targeting the TSH receptor (TSH-R) induce hyperthyroidism in Graves´ disease (GD). Graves´ orbitopathy (GO) is influenced by stimulation of the TSH-R in the orbita. GO has been, among other factors, linked to high TRAb levels. Thyroid stimulating immunoglobulins (TSI) is a relatively new method for assessing TSH-receptor antibodies. The aim of this study was to investigate the role of TSI in the management of GO.

METHODS

Patients with newly diagnosed GD (n=30, median age 55 years (range 35-72), 29 women) received pharmacological therapy (methimazole+++thyroxine) for up to 24 months. GO was identified by clinical signs and symptoms. Eleven patients had GO at diagnosis, and another six developed GO during treatment. Blood samples for TSI and other thyroidal biomarkers were obtained at baseline and on five occasions during the 24-month follow-up. Twenty-two subjects completed the drug regimen without surgery or radioiodine treatment.

RESULTS

At baseline, TSI was highly correlated with TRAb (r _s =0.64, p<0.001), and both assays similarly correlated to fT3 values. TSI and TRAb did not differ significantly between GO and non-GO patients for visit v1 (n=30, 17 GO during the whole study) or at follow-up (n=22, 12 GO during the whole study). During follow-up, levels of TSI and TRAb decreased and normalized in both groups.

CONCLUSION

The present study does not support any added benefit of TSI compared to TRAb for the prediction and management of GO.

Clinical significance of thyroglobulin antibodies and thyroid peroxidase antibodies in Graves' disease: a cross-sectional study

PURPOSE

The significance of thyroglobulin antibodies (TgAbs) and thyroid peroxidase antibodies (TPOAbs) in Graves' disease (GD) remains unclear. Therefore, this study aimed to clarify the clinical significance of TgAbs and TPOAbs in GD.

METHODS

A total of 442 patients with GD were recruited and divided into four groups based on TgAb and TPOAb positivity. Their clinical parameters and the characteristics of the groups were compared. Cox proportional hazard regression analysis was performed to assess risk factors for GD remission.

RESULTS

The free triiodothyronine (FT3) level was significantly higher in groups positive for TgAbs and TPOAbs than in the other groups. The FT3 to free thyroxine (FT4) (FT3/FT4) ratio was significantly higher and thyrotropin-stimulating hormone (TSH) receptor antibodies (TRAbs) were significantly lower in the TgAb+/TPOAb- group. Time to FT4 recovery was significantly shorter for groups negative for TPOAbs, whereas time to TSH recovery was significantly longer for groups positive for TPOAbs. Cox proportional hazard regression analysis revealed that TgAb positivity, prolonged treatment duration with antithyroid drugs, and Graves' ophthalmopathy treated with methylprednisolone were significantly associated with GD remission and that a smoking history, elevated FT3/FT4 ratio, and treatment with propylthiouracil hindered GD remission.

CONCLUSION

The contributions of TgAbs and TPOAbs to GD pathogenesis differ. Patients positive for TgAbs develop GD with lower TRAb titers and undergo earlier remission than those negative for TgAbs. Patients positive for TPOAbs develop GD with high TRAb titers and need a long time to achieve remission.

Sphingolipids in thyroid eye disease

Graves' disease (GD) is caused by an autoimmune formation of autoantibodies and autoreactive T-cells against the thyroid stimulating hormone receptor (TSHR). The autoimmune reaction does not only lead to overstimulation of the thyroid gland, but very often also to an immune reaction against antigens within the orbital tissue leading to thyroid eye disease, which is characterized by activation of orbital fibroblasts, orbital generation of adipocytes and myofibroblasts and increased hyaluronan production in the orbit. Thyroid eye disease is the most common extra-thyroidal manifestation of the autoimmune Graves' disease. Several studies indicate an important role of sphingolipids, in particular the acid sphingomyelinase/ceramide system and sphingosine 1-phosphate in thyroid eye disease. Here, we discuss how the biophysical properties of sphingolipids contribute to cell signaling, in particular in the context of thyroid eye disease. We further review the role of the acid sphingomyelinase/ceramide system in autoimmune diseases and its function in T lymphocytes to provide some novel hypotheses for the pathogenesis of thyroid eye disease and potentially allowing the development of novel treatments.

Novel Insight into Non-Genetic Risk Factors of Graves' Orbitopathy

An assessment of the risk of Graves' orbitopathy (GO) is an important challenge in Graves' disease (GD) management. The purpose of this study was to compare non-genetic parameters in GD patients with and without GO in order to find novel risk factors and to verify the factors already reported. A total number of 161 people, 70 with GO and 91 non-GO patients were included in this study. GO was confirmed to be associated with smoking, older age, higher TSH receptor antibodies (TRAb) and lower thyroglobulin antibody (TgAb) levels and hypercholesterolemia. We demonstrated the latter correlation even for only a mild increase in LDL cholesterol. Importantly, our study provides novel potential GO risk factors, including higher serum creatinine levels, higher MCV and lower PLT. If further confirmed, these new, simple and easily accessible potential GO markers may constitute valuable auxiliary markers in GO risk assessments. We additionally proved that in moderate to severe GO, gender-related differences attenuate. No impact of vitamin D deficiency in GO development in patients with 25-hydroxyvitamin D [25(OH)D] > 20 ng/mL was found. The present report provides a set of GO risk factors, which can be used as a precise tool for an individual GO risk assessment.

Current concepts regarding Graves' orbitopathy

Graves' orbitopathy (GO) is an orbital autoimmune disorder and the main extrathyroidal manifestation of Graves' disease, the most common cause of hyperthyroidism. GO affects about 30% of Graves' patients, although fewer than 10% have severe forms requiring immunosuppressive treatments. Management of GO requires a multidisciplinary approach. Medical therapies for active moderate-to-severe forms of GO (traditionally, high-dose glucocorticoids) often provide unsatisfactory results, and subsequently surgeries are often needed to cure residual manifestations. The aim of this review is to provide an updated overview of current concepts regarding the epidemiology, pathogenesis, assessment, and treatment of GO, and to present emerging targeted therapies and therapeutic perspectives. Original articles, clinical trials, systematic reviews, and meta-analyses from 1980 to 2021 were searched using the following terms: Graves' disease, Graves' orbitopathy, thyroid eye disease, glucocorticoids, orbital radiotherapy, rituximab, cyclosporine, azathioprine, teprotumumab, TSH-receptor antibody, smoking, hyperthyroidism, hypothyroidism, thyroidectomy, radioactive iodine, and antithyroid drugs. Recent studies suggest a secular trend toward a milder phenotype of GO. Standardized assessment at a thyroid eye clinic allows for a better general management plan. Treatment of active moderate-to-severe forms of GO still relies in most cases on high-dose systemic-mainly intravenous-glucocorticoids as monotherapy or in combination with other therapies-such as mycophenolate, cyclosporine, azathioprine, or orbital radiotherapy-but novel biological agents-including teprotumumab, rituximab, and tocilizumab-have achieved encouraging results.

The Role of TPOAb in Thyroid-Associated Orbitopathy: A Systematic Review

INTRODUCTION

Thyroid-associated orbitopathy (TAO) is one of the most common autoimmune inflammatory disorders of the orbit. The presence of anti-thyroid antibodies is believed to play a role in the pathogenesis and clinical status of the TAO patients. Herein, we review the usefulness of TPOAb as a biomarker for TAO.

METHODS

A systematic search in MEDLINE library was conducted. Results: Twenty studies were included. TPO is expressed in orbital tissues, and the polymorphism rs11675434 SNP has proven to be associated with clinically evident TAO. Studies in pediatric patients have shown a positive correlation between high TPOAb levels and TAO. In contrast, results in adults are inconsistent. Some studies imply a protective role of TPOAb, yet the majority did not find any association. Some authors have suggested an implication of TPOAb in the pathophysiology of TAO in TRAb-negative patients.

CONCLUSIONS

The role of TPOAb in TAO remains unclear and controversial.

Clinical Characteristics of Patients with Euthyroid Thyroid-associated Ophthalmopathy

Purpose: To compare clinical features between thyroid-associated ophthalmopathy (TAO) patients with hyperthyroidism and euthyroidism.Methods: Between September 2015 and January 2021, we enrolled 96 TAO patients with euthyroidism (n = 16) or hyperthyroidism (n = 80). We recorded the age, sex, smoking status, presence of hypertension and diabetes, total follow-up period, unilateral involvement, eyelid edema, lid lag and retraction, clinical activity score (CAS), modified NOSPECS score, exophthalmometry, Hess test, area of extraocular muscles on orbital computed tomography (CT), treatment with systemic and subconjunctival steroids and radiotherapy, and serum levels of free thyroxine, thyroid-stimulating hormone (TSH), anti-thyroglobulin antibody (anti-Tg Ab), anti-thyroid peroxidase antibody (anti-TPO Ab), TSH receptor antibody (TSHR Ab), and thyroid stimulating antibody.Results: Unilateral involvement was significantly more common in the euthyroid group, while conjunctival injection, CAS, extraocular muscle movement restriction within 10° on the Hess chart, maximum cross-sectional area of the inferior rectus on orbital CT, and treatment with intravenous high-dose steroid were significantly more common in the hyperthyroid group. Furthermore, the modified NOSPECS score and levels of free thyroxine, anti-Tg Ab, anti-TPO Ab, and TSHR Ab were significantly higher in the hyperthyroid than euthyroid group.Conclusions: Compared to hyperthyroid TAO patients, those with euthyroid TAO were more likely to have unilateral involvement. They also had lower clinical activity and severity, milder enlargement of extraocular muscles (EOMs), and lower rates of EOM movement restriction and treatment with intravenous high-dose steroid. Euthyroid TAO patients had lower levels of free thyroxine, anti-Tg Ab, anti-TPO Ab, and TSHR Ab compared to hyperthyroid TAO patients.

An Early Wave of Macrophage Infiltration Intertwined with Antigen-Specific Proinflammatory T Cells and Browning of Adipose Tissue Characterizes the Onset of Orbital Inflammation in a Mouse Model of Graves' Orbitopathy

Background: Graves' orbitopathy (GO) is an autoimmune-driven manifestation of Graves' disease (GD) where pathogenic autoantibodies to the thyrotropin receptor (TSHR) activate orbital fibroblasts/preadipocytes in the orbital tissue to induce inflammation and extracellular matrix deposition. Since there are significant limitations to study immunological and proinflammatory mediator expression in early and during disease progression in GO patients, we used our experimental mouse model to elucidate early pathogenic processes. Methods: We have developed a robust mouse model of GD/GO induced by electroporation immunization of plasmid encoding human TSHR A-subunit, comprising multiple injections over a course of 15 weeks to fully recapitulate the orbital pathology. In this study, we investigated kinetics of GO development in the model by serial analyses of immunological and cellular parameters during course of orbital inflammation. Results: Pathogenic anti-TSHR antibodies with thyroid-stimulating properties developed early after the second immunization step with concomitant induction of hyperthyroidism. Examination of orbital tissue showed an early wave of macrophage infiltration followed subsequently by CD3⁺ T cells into the orbital tissue. Examination of antigen-specific T cell activity using recombinant human A-subunit protein showed high CD8⁺ T cell proliferation during this early phase of disease onset, whereas effector CD4⁺ T cells and CD25⁺FOXP3⁺ regulatory T cells (Tregs) were downregulated. The early phase of disease was also characterized by abundant presence of proinflammatory cytokines interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α). Moreover, as the disease progressed, there was significant increase in browning of orbital fat tissue, which may be dependent on the proinflammatory milieu and/or the increased thyroid hormone levels during the established hyperthyroid status. Conclusions: This work revealed early infiltration of macrophages in the orbital region and induction of pathogenic anti-TSHR antibodies during disease onset in the model. This was followed subsequently by influx of CD8⁺ T cells specific for TSHR coupled with reduction in Tregs and substantial increase in brown adipose tissue. These new insights into the development of orbital inflammation in the model have implications for testing new therapeutic regimens by targeting macrophage function during early phases of orbital inflammation in the model.

Relationship between Serum Thyroid-stimulating Hormone Receptor Autoantibodies and Activity and Severity of Thyroid Eye Disease

Purpose: To study the relationship between the levels of serum thyroid-stimulating hormone (TSH)-receptor autoantibodies (TRAbs) and thyroid eye disease (TED) activity and severity scores.Methods: A cross-sectional study was performed. The medical records of 315 patients diagnosed with TED between March 2014 and December 2019 were reviewed. The clinical activity score (CAS) was used to assess TED activity and a modified NOSPECS score was used for severity grading. The serum TRAb level was measured using two assays: a TSHR binding inhibitory immunoglobulin (TBII) assay and thyroid stimulating immunoglobulin (TSI) bioassay.Results: The TBII and TSI assay results were significantly positively correlated with the CAS (R = 0.113 and 0.211, respectively; p < 0.05), modified NOSPECS score (R = 0.173 and 0.316, respectively; p < 0.05), and proptosis (R = 0.136 and 0.167, respectively; p < 0.05). Both assays demonstrated significant differences in the level of TRAb between patients with and without compressive optic neuropathy or corneal epithelial defects.Conclusions: The levels of TRAbs according to both TBII and TSI assays showed significant correlations with clinical signs of corneal involvement, optic neuropathy, and TED activity and severity.

Serum thyroglobulin is associated with orbitopathy in Graves' disease

PURPOSE

Serum thyroglobulin levels are often elevated in Graves' disease (GD) and in most cases decrease during treatment. Its relation to Graves' orbitopathy (GO) has not been clarified. Previously, a risk of GO has been linked to smoking, TSH receptor stimulation, high TSH-receptor antibodies (TRAb), low thyroid peroxidase and thyroglobulin antibodies (TPOAb, TgAb).

METHODS

We examined Tg levels in 30 consecutive patients with GD were given drug therapy (methimazole + thyroxine) for up to 24 months. GO was identified by clinical signs and symptoms. 17 patients had GO, 11 of whom had it at diagnosis while 6 developed GO during treatment. During the study, 5 subjects were referred to radioiodine treatment, 3 to surgery. The remaining 22 subjects (GO n = 12, non-GO n = 10) completed the drug regimen.

RESULTS

At diagnosis, Tg levels in GO patients (n = 11) were higher (84, 30-555 µg/L, median, range) than in non-GO patients (n = 19) (38, 3.5-287 µg/L), p = 0.042. Adding the 6 subjects who developed eye symptoms during treatment to the GO group (n = 17), yielded p = 0.001 vs. non-GO (n = 13). TRAb tended to be higher, while TPOAb and TgAb tended to be lower in the GO group. For the 22 patients who completed the drug regimen, Tg levels were higher in GO (n = 12) vs. non-GO (n = 10), p = 0.004, whereas TRAb levels did not differ.

CONCLUSION

The data may suggest that evaluation of thyroglobulin levels in GD could contribute to identify patients at increased risk of developing GO. Possibly, thyroidal release of Tg in GD reflects a disturbance that also impacts retroorbital tissues.

Thyrotropin receptor antibodies and Graves' orbitopathy

CONTEXT AND PURPOSE

The thyrotropin receptor (TSHR) is the key autoantigen in Graves' disease (GD) and associated orbitopathy (GO). Antibodies targeting the TSHR (TSHR-Ab) impact the pathogenesis and the course of GO. This review discusses the role and clinical relevance of TSHR-Ab in GO.

METHODS

Review of the current and pertinent literature.

RESULTS

GO is the most common extrathyroidal manifestation of GD and is caused by persistent, unregulated stimulation of TSHR-expressing orbital target cells (e.g. fibroblasts and pre-adipocytes). Serum TSHR-Ab and more specifically, the stimulatory Ab (TSAb) are observed in the vast majority of patients with GD and GO. TSHR-Ab are a sensitive serological parameter for the differential diagnosis of GO. TSHR-Ab can be detected either with conventional binding immunoassays that measure binding of Ab to the TSHR or with cell-based bioassays that provide information on their functional activity and potency. Knowledge of the biological activity and not simply the presence or absence of TSHR-Ab has relevant clinical implications e.g. predicting de-novo development or exacerbation of pre-existing GO. TSAb are specific biomarkers of GD/GO and responsible for many of its clinical manifestations. TSAb strongly correlate with the clinical activity and clinical severity of GO. Further, the magnitude of TSAb indicates the onset and acuity of sight-threatening GO (optic neuropathy). Baseline serum values of TSAb and especially dilution analysis of TSAb significantly differentiate between thyroidal GD only versus GD + GO.

CONCLUSION

Measurement of functional TSHR-Ab, especially TSAb, is clinically relevant for the differential diagnosis and management of GO.

Prevalence of thyroid eye disease in Graves' disease: A meta-analysis and systematic review

OBJECTIVE

Thyroid eye disease (TED) is a debilitating condition that frequently manifests in patients suffering from Graves' disease (GD). This study aims to analyse the prevalence of TED among GD patients, with a focus on geographical region-specific rates.

METHODS

Medline and Embase were searched for articles examining TED prevalence on April 2020, and articles were retrieved and sieved. Statistical analysis was performed after Freeman-Tukey double arcsine transformation. Thereafter, results were pooled with random effects by DerSimonian and Laird model.

RESULTS

Fifty-seven articles involving 26,804 patients were included in the review. The overall pooled prevalence of TED was 40% (CI: 0.32 to 0.48) and by continent was 38% (CI: 0.31 to 0.46) for Europe, 44% (CI: 0.32 to 0.56) for Asia, 27% (CI: 0.06 to 0.56) for North America and 58% (CI: 0.55 to 0.61) for Oceania. The prevalence of TED in Southeast Asia was 35% (CI: 0.24 to 0.47) and Middle East 48% (CI: 0.19 to 0.78). Subgroup analysis showed regions with predominantly Caucasians (37%; CI: 0.28 to 0.46) had a lower prevalence of TED compared to Asians (45%; CI: 0.33 to 0.58). The pooled prevalence of lid retraction was 57% (CI: 0.39 to 0.74), proptosis 57% (CI: 0.48 to 0.65), diplopia 36% (CI: 0.24 to 0.48) and ocular hypertension 13% (CI: 0.06 to 0.19).

CONCLUSION

A substantial proportion of patients with GD have TED and often manifest as lid retraction, proptosis and diplopia. Early detection through active screening might help to mitigate the progression of TED and its associated complications.

Thyroid autoantibodies in adults with acquired binocular diplopia of unknown origin

Patients with acquired adult-onset strabismus mainly present with binocular diplopia. Although cranial nerve palsies are reportedly the most common cause of binocular diplopia in adults, thyroid disease can also cause diplopia. In patients with thyroid-associated ophthalmopathy, upper lid retraction and proptosis are the most common initial findings, but diplopia could be the first manifestation. So far, there has been little information on the diagnostic value of thyroid autoantibodies in patients with strabismus. Therefore, we examined adults with acquired binocular diplopia from 2008 to 2016 and evaluated the presence of thyroid autoantibodies and the relationship between thyroid autoantibody status and clinical characteristics in adults with acquired binocular diplopia. Thyroid autoantibody tests were performed for all patients, unless other causes of diplopia were identified. Fifty one (39%) of 132 patients were positive for thyroid autoantibodies. In the thyroid autoantibody-positive (TAb+) group, microsomal autoantibodies, thyroid-stimulating hormone receptor antibodies, thyroglobulin antibodies, and thyroid-stimulating antibodies were observed in 30, 27, 12, and 7 patients, respectively. The vertical deviation and grade of duction limitation were greater in the TAb+ group. The presence of ocular torsion was 15.5% and 39.5% in the TAb- and TAb+ groups, respectively. Thyroid autoantibody evaluation may be helpful in adults with idiopathic acquired binocular diplopia.

Epidemiology, Natural History, Risk Factors, and Prevention of Graves' Orbitopathy

GO is the most frequent extrathyroidal manifestation of Graves' disease, although it may rarely occur in euthyroid/hypothyroid patients with chronic autoimmune thyroiditis. It is a relatively infrequent disorder, and men tend to have more severe ocular involvement at an older age. The prevalence of GO is lower than in the past among patients with recent onset Graves' hyperthyroidism, and moderate-to-severe forms requiring aggressive treatments are no more than 5-6% of all cases of GO. After an initial inflammatory (active) phase and a phase of stabilization (plateau phase), GO tends to improve and eventually inactivates (inactive or burnt-out phase). Minimal-to-mild GO often remits spontaneously, but complete restitutio ad integrum almost never occurs when GO is more than mild. Several risk factors contribute to its development on a yet undefined genetic background. Cigarette smoking is the most important of them. Early diagnosis, control and removal of modifiable risk factors, early treatment of mild forms of GO may effectively limit the risk of progression to more severe forms, which have a profound and dramatic impact on the quality of life of affected individuals, and remain a therapeutic challenge, often requiring long-lasting and multiple medical and surgical therapies.

The association between cigarette smoking and serum thyroid stimulating hormone, thyroid peroxidase antibodies and thyroglobulin antibodies levels in Chinese residents: A cross-sectional study in 10 cities

Objectives

Although several studies have shown that cigarette smoking is associated with thyroid stimulating hormone (TSH), thyroid peroxidase antibody (TPOAb) and thyroglobulin antibody (TgAb), the exact relationship between smoking and thyroid function is controversial. As little is known about the effects of smoking on TSH, TPOAb and TgAb in Chinese residents. This study aimed to evaluate the association between cigarette smoking and TSH, TPOAb and TgAb in ten-city residents of China.

Study design

This was a population-based cross-sectional study.

Methods

In this cross-sectional study, 15,181 subjects from ten major cities of China were investigated. Data regarding demographic characteristics, smoking status and consumption of iodine status were collected using in-person interviews based on a self-designed structured questionnaire. Serum concentrations of TSH, TPOAb and TgAb were measured using electrochemiluminescence immunoassays. Univariate analysis and multivariate linear stepwise regression analyses were used to analyze the data.

Results

The regular smokers had lower concentrations of TSH, TPOAb and TgAb than occasional smokers, former smokers and never smokers. Multivariate analysis demonstrated that regular smoking was associated with the decreased concentrations of TSH (β = -0.178), TPOAb (β = -0.287) and TGAb (β = -0.453) after adjusting other factors. Furthermore, daily smoking number was significantly associated with the decreased level of TSH (β = -0.045) and TPOAb(β = -0.080), and smoking duration was associated with the decreased TSH level (β = -0.030).

Conclusions

Our findings suggest that cigarette smoking is related to a significant decline in the concentrations of TSH, TPOAb and TgAb. In addition, daily smoking number and long-term smoking decrease serum TSH and TPOAb levels. Cigarette smoking plays a significant role in the development of thyroid dysfunction.

Clinical, Hormonal, and Ultrasound Characteristics of Patients with Newly Diagnosed Graves’ Disease And Different Thyroid Antibody Profiles

Objective: Graves’ disease (GD) is characterized by elevated TSH-receptor antibodies (TRAb) and less often – thyroid peroxidase (TPOAb) and thyroglobulin antibodies (TgAb). Our aim was to examine the hormonal and ultrasound characteristics of patients with newly diagnosed GD with differing positive thyroid antibodies.

Materials and Methods: This study included 249 patients with newly diagnosed GD (191 women, 58 men). 40.2% of them had Graves’ ophtalmopathy. The serum levels of TSH, free T4, free T3, TRAb, TPOAb, and TgAb were measured with third generation ECLIA assays (Roche Diagnostics, Switzerland). Thyroid ultrasound was performed with a Fukuda-Denshi 550 device (Fukuda Corp., Japan) and an Ultrasonix device (Ultrasonix Medical Corp., Canada). Statistical analyses were done using the SPSS 23.0 statistical package (Chicago, IL).

Results: 64% of the patients were TPOAb+ and 36% − TgAb+. One third were only TRAb+, 1/3 had two positive antibodies (TRAb + second antibody) and 1/3 – all three positive antibodies. Patients with more positive antibodies tended to be younger, had higher fT4, TRAb levels, thyroid volume but rarely had nodules on US and accompanying GO. Positive TPOAb antibodies were found in younger patients, with higher fT4 and TRAb levels, higher thyroid volume and lower prevalence of nodules and GO. The same trends were found in patients with positive TgAb.

Conclusion: The different characteristics of GD patients with varying thyroid antibody profiles may be due to a variation in the pathogenesis of the disease. An individualized clinical approach may be suitable in those cases.

Usefulness of TSH receptor antibodies as biomarkers for Graves' ophthalmopathy: a systematic review

PURPOSE

Over the past several decades, many papers have been published about the usefulness of thyrotropin receptor antibodies (TRAbs) as biomarkers of Graves' ophthalmopathy (GO). However, results have been inconsistent. The purpose of this analysis is to determine a possible cause of these discrepancies and to examine the usefulness of TRAbs as biomarkers for GO, especially 'thyrotropin-binding inhibiting immunoglobulin (TBII)' and 'thyroid-stimulating antibody (TSAb)'.

METHOD

26 articles discussing the association between TRAbs and GO were selected which were then divided into three groups based on the study method and whether or not the patients had been treated for hyperthyroidism. From the results of the papers reviewed, a provisional conclusion was made and a theoretical model on the TBII-TSAb coordinate plane was developed to confirm that conclusion.

RESULTS

TSAb is reported to be significantly or strongly associated with GO in the studies of pre- and post-treated patients for hyperthyroidism. TBII is positively correlated, negatively correlated or uncorrelated with GO in studies of pre-treated patients. However, it is generally agreed upon that TBII and GO are closely correlated in studies of post-treated patients.

CONCLUSION

We conclude that the level of TBII may not be a reliable indicator of the current state of GO in pre-treated patients. Whereas, in post-treated patients, due to changes in the correlation between TBII and TSAb due to the effect of hyperthyroidism treatment, the level of TBII can be a more reliable indicator of GO. Furthermore, the current level of TBII is closely associated with the onset and severity of GO in the future and it can be a valid predictor of GO. However, the TSAb level appears to be more reliable.

Thyroid-Associated Orbitopathy and Biomarkers: Where We Are and What We Can Hope for the Future

Background

Thyroid-associated orbitopathy (TAO) is the most common autoimmune disease of the orbit. It occurs more often in patients presenting with hyperthyroidism, characteristic of Graves' disease, but may be associated with hypothyroidism or euthyroidism. The diagnosis of TAO is based on clinical orbital features, radiological criteria, and the potential association with thyroid disease. To date, there is no specific marker of the orbital disease, making the early diagnosis difficult, especially if the orbital involvement precedes the thyroid dysfunction.

Summary

The goal of this review is to present the disease and combine the available data in the literature concerning investigation of TAO biomarkers.

Conclusions

Despite the progress done in the understanding of TAO disease, some important pieces are still missing. Typically, for the future, major efforts have to be done in the discovery of new biomarkers, validation of the suspected candidates on multicenter cohorts with standardized methodologies, and establishment of their clinical performances on the specific clinical application fields in order to improve not only the management of the TAO patients but also the therapeutic options and follow-up.

Advances in the management of thyroid eye diseases: An overview

INTRODUCTION

Thyroid eye disease (TED) remains a notorious ailment for both patients and the treating ophthalmologists. Recent years have witnessed considerable research in the immunopathogenic mechanism of TED that has resulted in an expansion and modification of the available management options.

AIM

Purpose of this review is to summarise the advances in the management of thyroid ophthalmopathy.

MATERIAL AND METHOD

A thorough literature search and of the past 10 years web search with words Thyroid ophthalmopathy, recent, advances.

RESULTS

Recent VISA classification and new serum markers seem to have potential to give diagnostic as well as therapeutic guidance, gauge treatment response and even identify risk of disease progression. Majority of TED patients can be managed conservatively due to its self-limiting nature but if indicated, still steroids are the preferable medical therapy; however, there is an increasing consensus towards the use of parenteral form as compared to the oral one on account of greater efficacy with lesser side effects. Steroid sparing medications, for example, rituximab, infliximab, etanercept, adalimumab, teprotumumab, tocilizumab, tanshinone, are showing encouraging results and form an area of active research.

CONCLUSION

Radiation therapy remains as an adjunctive modality in active diseases as a nonmedical treatment for TED with some promising data. Surgical intervention may be required in vision threatening conditions or to counteract the sequel of inflammatory phase. Advances in surgical techniques like stereotactic image-guided balanced orbital decompression with endoscopic approach ensure meticulous dissection with minimal trauma.

Radiographic evidence of prominent retro and suborbicularis oculi fat in thyroid-associated orbitopathy

PURPOSE

To compare the radiological differences in retro-orbicularis oculi fat (ROOF) and suborbiculars oculi fat (SOOF) among patients with thyroid-associated orbitopathy (TAO) and normal subjects using computed tomography (CT).

METHODS

A retrospective analysis of orbital CTs was performed in 39 consecutive patients, who were imaged between October 2005 and June 2009. Bilateral orbital CTs of 16 patients with a final report significant for thyroid orbitopathy and 23 normal subjects were evaluated. All of the CTs consisted of 0.75 mm thick axial slices with 1.5 mm coronal reconstructions. Using the axial soft tissue windows, the ROOF and SOOF tissues were identified. The maximum ROOF thickness was measured perpendicular to the frontal bone, immediately superior to the supraorbital rim. Similarly, the maximum SOOF thickness was measured perpendicular to the zygomatic bone, immediately inferolateral to the infraorbital rim. The radiologist was blinded to the CT reports while conducting the measurements. Multivariable analysis of the two groups was then performed for comparison.

RESULTS

Seventy-eight ROOF and SOOF measurements were obtained from 16 TAO patients with and 23 patients without TAO. The female-to-male ratio was 6:1 in the TAO group and only 3:2 among the normal subjects. The mean axial ROOF thicknesses was 3.8 ± 1.9 for TAO patients and 2.8 ± 1.0 mm in patients without TAO, while the SOOF thickness was 4.4 ± 1.0 and 3.4 ± 1.0 mm in the 2 groups, respectively. To account for bilateral measurements, the mixed model analysis was used. After controlling for age, gender, and ethnicity, the mean TAO ROOF and SOOF thicknesses were 1.0 mm (p = 0.04) and 0.9 mm (p < 0.01) greater than the control group, respectively.

CONCLUSION

Retro-orbicularis oculi fat (ROOF) and suborbicularis oculi fat (SOOF) hypertrophy are two additional radiologic CT measurements that may be valuable in establishing the diagnosis of thyroid-associated orbitopathy.

Does autoimmunity against thyroglobulin play a role in the pathogenesis of Graves' ophthalmopathy: a review

While most authors believe that autoimmunity against the TSH receptor expressed in the orbital connective tissue cells is the main reaction that leads to the development of ophthalmopathy in patients with Graves’ hyperthyroidism, an older hypothesis that deserves fresh consideration is based on the notion that thyroglobulin (Tg) in the thyroid gland passes in a retrograde fashion to the orbit where it is recognized by Tg autoantibodies, leading to inflammation. Here, we review new evidence that supports a role of Tg and propose a new hypothesis based on the notion that Tg is targeted in the orbit leading to a complex cascade of reactions that leads to Graves’ ophthalmopathy.

Prevalence, Phenotype, and Psychosocial Well-Being in Euthyroid/Hypothyroid Thyroid-Associated Orbitopathy

BACKGROUND

At the onset of thyroid-associated orbitopathy (TAO), most patients are hyperthyroid, while scarce data are available on euthyroid/hypothyroid TAO. The aim of this study was to assess the prevalence, phenotype, and psychosocial burden of patients with initially euthyroid/hypothyroid TAO.

METHODS

The medical records of 461 consecutive and unselected patients with TAO followed at a specialized joint thyroid-eye clinic were analyzed within this retrospective cross-sectional study. Main outcome measures were the prevalence of initially eu- or hypothyroid TAO as well as ophthalmic signs and symptoms, disease-specific quality of life (QoL), work impairment, and rate of psychotherapy in initially eu-/hypothyroid versus hyperthyroid TAO.

RESULTS

The prevalences of eu-/hypothyroid and hyperthyroid TAO were 4.3% (n=20; [confidence interval, CI, 2.6-6.3]) and 95.7% (n=441; [9.37-9.74]), respectively. In 12 patients (2.6% [CI 1.3-4.3]), Hashimoto's thyroiditis was present and in 8 (1.7% [CI 0.7-3.0]) no thyroid disease was noted at the time of inclusion. One (0.05%) patient with eu-/hypothyroid TAO and 172 (39%) with hyperthyroid TAO had clinically active TAO (p=0.001). In eu-/hypothyroid versus hyperthyroid patients, 14 (70%) versus 135 (30.6%) had a mild TAO, 6 (30%) versus 183 (64.2%) a moderate-to-severe TAO, and 0 versus 23 (5.4%) had a sight-threatening TAO (p<0.001). TAO was asymmetric in 4 (20%) eu-/hypothyroid and in 27 (6.1%) hyperthyroid patients (p=0.038). Only 5.3% versus 30.2% and 10.5% versus 44.1% of patients with eu-/hypothyroid and hyperthyroid TAO, respectively, were on sick leave (p=0.003) or work disabled (p=0.018). QoL was less impaired in eu-/hypothyroid versus hyperthyroid TAO (median visual functioning and appearance scores: 100 versus 75; p<0.001 and 81.25 versus 75; p=0.315). Of patients with eu-/hypothyroid and hyperthyroid TAO, 15% and 20.2% had psychotherapy respectively (p=0.409). Eu-/hypothyroid TAO was positively (odds ratio 7.05, p=0.060) and negatively (odds ratio: 0.09, p=0.026) associated with a unilateral involvement and thyrotropin-receptor autoantibodies respectively.

CONCLUSIONS

Compared with hyperthyroid TAO, QoL and working ability are less impaired in eu-/hypothyroid TAO with an often asymmetric and less severe clinical phenotype.

Thyroid Stimulating but Not Blocking Autoantibodies Are Highly Prevalent in Severe and Active Thyroid-Associated Orbitopathy: A Prospective Study

The clinical utility of the functional TSH receptor autoantibodies was prospectively evaluated in patients with thyroid-associated orbitopathy (TAO). Ophthalmic, endocrine, and serological investigations were performed in 101 consecutive patients with severe and active TAO. Serum thyroid stimulating (TSAb) and blocking (TBAb) antibody levels were measured with two bioassays using cells that express a chimeric TSH receptor and CRE-dependent luciferase. TSAb results are expressed as percentage of specimen-to-reference ratio (SRR %). Blocking activity is defined as percent inhibition of luciferase expression relative to induction with bovine TSH alone. All 101 consecutively followed-up patients with severe and active TAO were TBAb negative. In contrast, 91 (90%) were TSAb positive of whom 90 had Graves' disease. Serum TSAb levels correlated with the diplopia score (P = 0.016), total severity eye score (P = 0.009), proptosis (P = 0.007), lid aperture (P = 0.003), upper lid retraction (P = 0.006), keratopathy (P = 0.04), and thyroid binding inhibiting immunoglobulins (TBII, P < 0.001) and negatively with the duration of TAO (P = 0.002). Median serum values of TSAb were SRR% 418 (range 28% to 795%). TSAb, not TBAb, are highly prevalent in severe/active TAO and serum TSAb levels correlate with clinical disease severity.

Clinical characteristics of Graves' orbitopathy in patients showing discrepancy between levels from TBII assays and TSI bioassay

OBJECTIVE

To investigate clinical characteristics of patients with Graves' orbitopathy (GO) who showed discrepancies between levels of thyroid-stimulating immunoglobulin (TSI) and thyrotropin-binding inhibitory immunoglobulin (TBII).

DESIGN

Comparative case series.

PATIENTS

A total of 317 patients with GO in whom Mc4-TSI and M22-TRAb (third-generation TBII) were measured simultaneously. Patients were divided into four groups according to TRAb levels as followings: Group 1, TBII and TSI < median value; Group 2, TBII ≥ median, TSI < median; Group 3, TBII < median, TSI ≥ median; Group 4, both TBII and TSI ≥ median.

MEASUREMENT

Endocrine and ophthalmic clinical manifestations in each group.

RESULTS

The median value of M22-TRAb was 6·11 IU/l and that of Mc4-TSI was 415·1 (SRR%). One hundred seventeen patients were classified as Group 1, 41 patients as Group 2, 41 patients as group 3 and 118 patients as group 4. Mean CAS was significantly higher in Groups 3 (2·2) and 4 (2·2) than in Groups 1 (1·6) and 2 (1·4; P = 0·001, ANOVA). Mean modified NOSPECS scores were significantly higher (P < 0·001, ANOVA) in Groups 3 (4·1) and 4 (4·1) than in Groups 1 (3·1) and 2 (2·3). The proportion of patients with hyperthyroidism was larger in Group 2 (85·4% [35/41 patients]) than in Group 3 (48·8% [20/41 patients]; P = 0·002).

CONCLUSIONS

GO is more active and severe in patients with predominant Mc4-TSI than in patients with predominant M22-TRAb. Patients with hyperthyroidism were more likely to be included with patients with predominant M22-TRAb than with predominant Mc4-TSI.

Graves' ophthalmopathy: epidemiology and natural history

Graves' ophthalmopathy (GO) is an autoimmune disorder of the orbit that is clinically relevant in 25-50% of patients with Graves' disease and 2% of patients with chronic thyroiditis. The age-adjusted annual incidence of clinically relevant GO is 16 per 100,000 population in women and 2.9 in men. At the onset of ophthalmopathy, 80-90% of patients have hyperthyroidism, with the rest having euthyroidism or hypothyroidism. The natural history of GO consists of two phases: an active inflammatory phase and a static phase. Anti-inflammatory therapy is indicated for the first phase of GO. Approximately 5% of patients experience late reactivation of GO. Asians appear to have less severe manifestations, with milder orbital edema, proptosis and muscle restriction. Genetic, anatomic and environmental factors influence the development of GO. Aging, thyroid dysfunction, thyroid stimulating hormone (TSH) receptor antibodies, smoking and radioiodine treatment for hyperthyroidism also influence the development and course of GO.

Correlation between TSH receptor antibody assays and clinical manifestations of Graves' orbitopathy

PURPOSE

To investigate an association between the levels of serum thyroid-stimulating hormone (TSH)-receptor autoantibodies (TRAbs) and Graves' orbitopathy (GO) activity/severity scores, and compare the performance of three different TRAb assays in assessing the clinical manifestations of GO.

MATERIALS AND METHODS

Cross-sectional study. Medical records of 155 patients diagnosed with GO between January 2008 and December 2010 were reviewed. GO activity was assessed by clinical activity score (CAS) and severity graded with the modified NOSPECS score by a single observer. Serum TRAb was measured by three different methods: 1st generation thyrotropin-binding inhibitor immunoglobulin (TBII) assay (TRAb1st); 3rd generation TBII assay (TRAb3rd); and biological quantitative assay of thyroid-stimulating immunoglobulin (TSI) using Mc4-CHO cells (Mc4-CHO TSI assay). Results were correlated with scores of activity/severity of thyroid eye disease.

RESULTS

All three assays (TRAb1st, TRAb3rd, and Mc4-CHO TSI) yielded results that were significantly positively correlated with CAS (β=0.21, 0.21, and 0.46, respectively; p<0.05) and proptosis (β=0.38, 0.34, and 0.33, respectively; p<0.05). Mc4-CHO TSI bioassay results were significantly positively correlated with all GO severity indices (soft tissue involvement, proptosis, extraocular muscle involvement, and total eye score; β=0.31, 0.33, 0.25, and 0.39, respectively; p<0.05).

CONCLUSION

Mc4-CHO TSI bioassay was superior over the two TBIIs in assessing active inflammation and muscle restriction due to GO, whereas TBII assay would be sufficient for evaluation of patients with proptosis.

Relevance of TSH-receptor antibody levels in predicting disease course in Graves' orbitopathy: comparison of the third-generation TBII assay and Mc4-TSI bioassay

AIMS

To investigate if TSH-receptor antibody (TRAb) levels measured in early Graves' orbitopathy (GO) stages are predictive of clinical disease course beyond 1 year after initial GO diagnosis and to compare performance of two newly developed TRAb assays (third-generation thyrotropin-binding inhibitor immunoglobulin (TBII) assay vs Mc4-thyroid-stimulating immunoglobulin (TSI) bioassay) in predicting disease course.

METHODS

Newly diagnosed, untreated GO patients whose duration of ocular symptoms was less than 6 months were included. One year after initial diagnosis, all patients were classified as presenting either a mild (Group 1) or severe course (Group 2) according to their clinical manifestations. The measurements of two TRAb assays at initial GO diagnosis were used for analysis.

RESULTS

Data from 112 patients were available for analysis. Seventy-three patients (65.2%) were designated as Group 1, and 39 patients (34.8%) as Group 2. Patients with higher initial TRAb levels demonstrated a higher risk of severe disease course upon multiple regression analysis (P<0.01). The cutoff values for the prediction of severe course of the third-generation TBII and Mc4-TSI assays were 10.67 IU/l and 555.10%, respectively, with assay specificities of 84.9 and 89.0%. The TBII assay predictive power (area under the curve (AUC)=0.817; 95% confidence interval (CI) =0.732-0.902) was equivalent to the TSI bioassay (AUC=0.868, 95% CI=0.803-0.934) (P=0.203).

CONCLUSIONS

The predictive power of the third-generation TBII assay and Mc4-TSI bioassay are similarly strong. Measurement of TRAb using either third-generation TBII or Mc4-TSI in early GO periods would provide important prognostic information on future GO course.

Clinical features of thyroid-associated ophthalmopathy in clinically euthyroid Korean patients

AIM

To compare clinical characteristics and thyroid-stimulating hormone receptor antibodies (TRAbs) in thyroid-associated ophthalmopathy (TAO) in euthyroid Korean patients with those in hyperthyroid patients.

METHODS

Clinical activity scores (CASs), modified NOSPECS scores, exophthalmometry values, prevalence of optic neuropathy, restrictive myopathy and lid retraction, and the positivity and levels of TRAb (thyrotropin-binding inhibitor immunoglobulin (TBII) and thyroid-stimulating immunoglobulin (TSI)) were compared in 24 euthyroid (group A) and 139 clinical/subclinical hyperthyroid TAO patients (group B).

RESULTS

Group A presented more clinically unilateral involvement than group B (79.2% vs 27.3%, P<0.001), less active (CAS 1.50 vs 2.26, P=0.014) and less severe clinical course (NOSPECS 3.38 vs 4.13, P=0.037). Lid retraction was more prevalent in group A than group B (91.7% vs 66.2%, P=0.014). Prevalence of optic neuropathy and restrictive myopathy, and the mean value of exophthalmometry were not different. Mean TBII levels were lower (7.20 IU/l) in group A than in group B (44.58 IU/l, P<0.001). A similar difference was found in the TSI bioassay (201.40% vs 425.19%, P=0.001). The positive rate of TBII in group A (34.8%) was significantly lower than in group B (90.8%, P<0.001). The positive rate of TSI was high in both group A (83.3%) and B (91.7%), with no significant difference (P=0.337).

CONCLUSIONS

Patients with euthyroid TAO showed a less active and severe clinical course, more unilateral involvement, and lower levels of TRAb than those in patients with hyperthyroid TAO. These distinct clinical and biochemical characteristics might be useful in assessment of euthyroid TAO, and the TSI might be more sensitive for diagnosing these patients.

Ethnic differences in the clinical presentation of Graves' ophthalmopathy

Ethnic differences in a number of eye conditions have been described. The literature on ethnic differences in Graves' ophthalmopathy (GO) is limited. There is some evidence to suggest Asian patients with GO may manifest milder phenotypic features of GO, with less proptosis and evidence of extraocular muscle involvement and restriction. The reasons for these differences are likely to be multifactorial and include orbital and lid anatomy, genetic background and autoimmune responses including TSH -receptor antibodies. These differences should be kept in mind when evaluating and managing patients with GO.

Prevention of Graves' ophthalmopathy

Smoking is the most important risk factor for the occurrence/progression of Graves' ophthalmopathy (GO), as well as for its lower/slower response to immunosuppression. Accordingly, refrain from smoking should be urged, both as primary prevention (removal of risk factors in Graves' patients without GO), secondary prevention (early detection and treatment of asymptomatic/very mild GO) and tertiary prevention (reduction of complications/disability of overt GO). A 6-month course of 200 μg/day sodium selenite can prevent progression of mild GO to more severe GO and is, therefore, a form of secondary prevention and, probably, primary prevention. Correction of thyroid dysfunction and stable maintenance of euthyroidism are important preventive measures. The optimal treatment for hyperthyroidism in patients with GO is uncertain, because evidence demonstrating the superiority of antithyroid drugs over thyroid ablation (radioiodine, thyroidectomy, or both) is lacking. If radioiodine is used, low-dose steroid prophylaxis is recommended, particularly in smokers, to prevent radioiodine-associated GO progression.

Treating the thyroid in the presence of Graves' ophthalmopathy

The etiology of Graves' orbitopathy (GO) remains enigmatic. Optimal therapeutic choices for the hyperthyroidism associated with Graves' disease (GD) in the presence of GO remain controversial. Whether antithyroid drugs (ATDs), radioiodine (RAI), or thyroidectomy should be favored in such patients remains debated. Pre-therapy variables such as ethnicity, sex, age, thyroid function, level of TSH-receptor antibodies and smoking behavior influence response to therapy. Among the most important management goals are restoring euthyroidism and abstaining from smoking. On average, ATDs and thyroidectomy - independent of extent - do not influence the natural course of GO. RAI can cause de novo development or progression of GO, which is largely preventable with oral steroid prophylaxis. In patients with mild GO, the thyroid treatment is largely independent of GO. Moderate to severe GO should be treated promptly. Deciding whether, in the latter, GD is better treated with ATDs, RAI, or surgery, is based more on expert opinion than on evidence. It is clear that in the individual patient a number of factors, not addressed in any trial, influence the final choice of therapy for GD, including concern of developing or negatively affecting pre-existing GO. Evidently, there is room for improving therapy of GO. Progress using novel drugs such as rituximab, which might potentially influence positively both GD and GO, are impatiently awaited.

Clinical relevance of thyroid-stimulating immunoglobulins in graves' ophthalmopathy

PURPOSE

Thyroid-stimulating immunoglobulins (TSIs) likely mediate Graves' ophthalmopathy (GO). The clinical relevance of these functional autoantibodies was assessed in GO.

DESIGN

Cross-sectional trial.

PARTICIPANTS

A total of 108 untreated patients with GO.

METHODS

Thyroid-stimulating immunoglobulins, assessed with a novel bioassay, bind to the thyrotropin receptor (TSHR) and transmit signals for cyclic adenosine monophosphate (cAMP)-dependent activation of luciferase gene expression. The cAMP/cAMP response element-binding protein/cAMP-regulatory element complex induces luciferase that is quantified after cell lysis. The TSI levels were correlated with activity and severity of GO and compared with a TSHR binding inhibitory immunoglobulin (TBII) assay.

MAIN OUTCOME MEASURES

Thyroid-stimulating immunoglobulins, activity and severity of GO, diplopia, and TBII.

RESULTS

Thyroid-stimulating immunoglobulins were detected in 106 of 108 patients (98%) with GO. All 53 hyperthyroid patients were TSI positive versus 47 patients (89%) who were TBII positive. All 69 patients with active GO were TSI positive, whereas only 58 of 69 patients (84%) were TBII positive. Thyroid-stimulating immunoglobulins correlated with the activity (r=0.83, P < 0.001) and severity (r=0.81, P < 0.001) of GO. All 59 patients with GO with diplopia were TSI positive, and 50 of 59 patients (85%) were TBII positive. Among patients with moderate-to-severe and mild GO, 75 of 75 (100%) and 31 of 33 (94%) were TSI positive compared with TBII positivity in 63 of 75 (84%) and 24 of 33 (73%), respectively. The TSI levels were higher in moderate-to-severe versus mild GO (489%±137% vs. 251%±100%, P < 0.001). Chemosis and GO activity predicted TSI levels alone (P < 0.001, multivariable analysis). The TSI levels were higher in patients with chemosis (527%±131%) than in patients without chemosis (313%±127%, P < 0.001).

CONCLUSIONS

Thyroid-stimulating immunoglobulins show more significant association with clinical features of GO than TBII and may be regarded as functional biomarkers for GO.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

The role of the innate immune recognition system in the pathogenesis of primary biliary cirrhosis: a conceptual view

The aetiology of primary biliary cirrhosis (PBC) remains unknown. Infectious and non-infectious noxious insults in combination with tissue-specific factors may precipitate PBC. Activation of innate immune response because of impending danger signals seems to be a key event in early PBC, as evidenced by granuloma formation, eosinophilic reaction and IgM elevation. Aberrant mitophagy in 'stressed' biliary epithelia cells may initiate the immune response against mitochondrial antigens. Antimitochondrial autoantibodies recognize evolutionarily conserved molecules. The question arises, whether they are pathogenic or rather an expression of beneficial autoimmunity. The generally stable course of PBC suggests that stimulatory and inhibitory autoimmune reactions govern the inflammatory biliary process. Tissue repair and defense are the heart of innate immunity. But continuous exposure of exogenous stimuli may precipitate functional antireceptor autoantibodies that are no more protective but rather harmful. Mitophagy, apoptosis and bile duct proliferation define the inflammatory response within bile ducts. Autoantigens may be clustered in different blebs on the surface of apoptotic cells targeting a variety of membrane and non-membrane-associated antigens. Thus, the autoantibody response in PBC may target, for instance, the pro- and anti-apoptotic proteins of the Bcl-2 family or receptors of the adrenergic or cholinergic system, hereby interfering with the programme of apoptosis and the proliferation of biliary epithelial cells. Consideration of there being functional autoantibodies into the pathogenesis of PBC may help to improve our understanding of the aetiopathogenesis of PBC.

Thyroid eye disease

Thyroid eye disease (TED) is the most common cause of proptosis in adults, and should always be a consideration in patients with unexplained diplopia, pain, or optic nerve dysfunction. At least 80% of TED is associated with Graves disease (GD), and at least 50% of patients with GD develop clinically evident symptomatic TED. The most confusing patients for doctors of all subspecialties are the patients with eye symptoms and signs that precede serum evidence of a thyroid imbalance. Management of TED may include immunosuppressive medications, radiation, or surgery. Although the prognosis for optic nerve function is excellent, the restrictive dysmotility can result in permanent disability. Orbit and eyelid reconstruction are reserved for stable, inactive patients and are the final steps in minimizing facial alterations and enhancing the patient's daily functioning.

Medical management of thyroid eye disease

Thyroid eye disease (TED) is the most common cause of orbital disease in adults. The immunologic pathogenesis of TED has been an area of active research and considerable progress has resulted in an expansion of therapeutic options. Although surgical intervention may be required, a majority of TED patients can be managed with medical therapies. Of medical therapies, glucocorticoids remain the agent of choice in the control of TED activity. The objective of this review is to discuss the paradigm and options in medical management of TED.

Risk factors for development or deterioration of Graves' ophthalmopathy

BACKGROUND

Graves' ophthalmopathy (GO) significantly impairs the quality of life of affected individuals and the most severe cases can be sight threatening. Given the limited therapeutic options, a strong emphasis should be placed on disease prevention to diminish the significant morbidity associated with this disease.

SUMMARY

GO is most prevalent in women and most severe in men. Although some genetic differences between GO patients and Graves' disease patients without ophthalmopathy have been identified, none of the polymorphisms identified to date impart a high enough risk of GO to justify genetic testing to guide therapy or preventive strategies. Poorly defined mechanical factors that appear also to play a role in GO susceptibility will likely be better elucidated with advances in imaging techniques. Tobacco smoking has been consistently linked to development or deterioration of GO. Smokers who receive radioactive iodine have the highest incidence of unfavorable GO outcome, which is proportional to the number of cigarettes smoked per day. Several studies have reported an association between radioactive iodine treatment for Graves' disease and worsening or development of GO. Observational studies suggest that the same appears to be true for thyroid dysfunction, including both hyper- and hypothyroidism. While thyrotropin receptor antibody levels appear to be useful in predicting the course of disease and response to therapy, it is not known whether they are predictive of GO development. The puzzling scenarios of euthyroid or clinically unilateral GO, the large number of nonsmoking GO patients, and the occasional development of GO years after thyroid dysfunction has been treated all underline the multifactorial etiology of this disorder in which no single factor determines the clinical outcome.

CONCLUSIONS

GO appears to have a complex genetic basis with multiple susceptibility alleles that act in combination with nongenetic factors to contribute to disease expression.

The influence of hepatitis C infection and interferon-alpha therapy on thyrotropin blocking and stimulating autoantibodies in Graves' ophthalmopathy: a case report

Background

Hepatitis C virus is a highly immunogenic pathogen often inducing autoimmune activation changes and this can often be further exacerbated by Interferon therapy. As HCV is lymphocytotropic, it can modulate T cell and B cell antibody responses, affecting many endocrine organs, most commonly the thyroid.

Case presentation

We hereby describe a case of fluctuating and wavering thyrotropin autoantibodies of both stimulating and blocking nature in the setting of Graves's ophthalmopathy, hepatitis C infection and interferon-α, causing hypo- and subsequently hyper-thyroidism. The autoantibody profile was clearly modified during interferon therapy and settled into a new equilibrium at the completion of treatment.

Conclusion

The case highlights the possible existence of a dual thyroid autoantibody population associated with hepatitis C, and its modulation by interferon therapy, which further compounds the difficulties in the assessment thyroid disease in this setting.

Cysteine 390 mutation of the TSH receptor modulates its ectodomain as an inverse agonist on the serpentine domain with decrease in basal constitutive activity

Mutations of individual cysteine residues at codon 301, 390, 398 and 408 of the thyrotropin receptor (TSHr) to serine resulted in cell surface expression of only C301S and C390S mutants. C390S mutation was a silencing mutation with decreased basal constitutive activity. Although the C301S and C390S mutants did not show any significant TSH binding, they generated cyclic AMP upon TSH stimulation. These mutants were also able to interact with stimulating and blocking anti-TSHr antibodies. In fact, C390S receptor is a more sensitive tool for blocking antibody detection than wild type receptor. Introduction of C390S to activating mutations in the ectodomain (S281N), exloop (I486F) and transmembrane (D633H) segments could not mute/nullify receptor activation. These data indicate that the C390S ectodomain behaves as a more effective inverse agonist on the noisy transmembrane segment and suggest that the basal and activated states of the receptor operate through two independent pathways.

Transconjunctival Müller muscle recession with levator disinsertion for correction of eyelid retraction associated with thyroid-related orbitopathy

PURPOSE

To evaluate the efficacy of transconjunctival Müller muscle recession and graded levator disinsertion for eyelid retraction in patients with thyroid-related orbitopathy (TRO).

DESIGN

Retrospective consecutive case series.

METHODS

Medical record review of 78 TRO patients (107 eyelids) who underwent surgery for upper eyelid retraction in a 5-year period was performed. Main outcome measures were anatomic and functional success, minimal reflex distance (MRD), lagophthalmos, eyelid asymmetry, and patient discomfort.

RESULTS

One hundred seven eyelid retraction surgeries were performed on 78 TRO patients (63 women, mean age 49 years); mean follow-up time was 16.7 months. Upper eyelid position, lagophthalmos, exposure keratopathy, and patients' discomfort markedly improved after surgery (P < .001). Marginal reflex distance (MRD1) decreased an average of 2.6 mm from 6 mm pre-operatively to 3.4 mm post-operatively (P < .001); lagophthalmos decreased an average of 0.6 mm from 1.3 mm pre-operatively to 0.4 mm post-operatively (P = .006) Failure rate was 8.4%, most improved with a second surgery. Overcorrection was noticed in three cases (2.8%). Eyelid asymmetry improved from a mean of 1.0 mm pre-operatively to 0.4 mm post-operatively (P = .001); more than 80% of patients showed eyelid asymmetry of 1 mm or less.

CONCLUSION

Transconjunctival Müller muscle and levator recession is safe and effective in correction of mild, moderate, or severe eyelid retraction in TRO patients. The failure rate is less than 10% and may be addressed by a second surgery.