Utility of ultra-portable ultrasound devices for the risk-stratification of thyroid dysfunctions in an emergency setting.

PURPOSE: We previously showed that the rapid TSH (rTSH) screening is able to detect a high prevalence of thyroid diseases in patients presenting to the Emergency department (ED), with a 7% prevalence of undiagnosed thyroid dysfunctions. The purpose of the present study is to implement our diagnostic flow-chart for thyroid dysfunctions in the ED with a rapid point-of-care thyroid ultrasound (rPOCUS). METHODS: rPOCUS was performed by an app-based mobile ultrasound device (Lumify® by Philips Healthcare) in patients with suppressed rTSH undergoing urgent procedures requiring iodinate contrast media. RESULTS: Our results suggest that rPOCUS is cost- and time-effective for the management of patients with a newly diagnosed hyperthyroidism requiring urgent iodinated contrast media or amiodarone administration. Moreover, this handled US scanner avoided rTSH measurement in patients found to have a normal thyroid gland, and detected some incidental findings (nodules, heterogeneous echotexture), which would lead to further diagnostic investigations. CONCLUSION: We demonstrate, for the first time, that rPOCUS greatly improves the management of patients attending the ED, including the prompt characterization and correct treatment of hyperthyroidism, and the prevention of iodine-induced thyrotoxicosis.

Fetal cell microchimerism and susceptibility to COVID-19 disease in women.

PURPOSE: The clinical outcome of COVID-19 disease is worse in males, and the reasons of this gender disparity are currently unclear, though evidences point to a combination of biological and gender-specific factors. A phenomenon unique to the female gender is the fetal cell microchimerism (FCM), defined as the presence of fetal microchimeric cells in maternal organs and in the circulation for years after delivery and usually evaluated by assessing the presence of male cells or DNA in a woman. In the present case-control study, we aimed to evaluate the possible effect of pregnancy and related FCM on the susceptibility to SARS-CoV-2 infection and on the clinical course and outcome of COVID-19. METHODS: One hundred twenty-three women with a previous male pregnancy, comprising 63 COVID-19 cases and 60 healthy controls were enrolled. The presence of blood male DNA was assessed by the amplification of the Y-chromosome specific gene SRY. RESULTS: The prevalence of male DNA of presumed fetal origin was significantly higher in healthy controls than in COVID-19 cases (70 vs 44.4%, P = 0.0044; OR 0.3429, 95% CI 0.1631-0.7207, P = 0.0047). Among women affected with COVID-19, the presence of male FCM did not significantly influence the severity of the disease, though the 8 deceased women studied were all FCM negative. CONCLUSION: This is the first case-control study reporting the prevalence of FCM in COVID-19 and healthy women. Overall, our data seem to suggest a role for FCM in the protection towards the SARS-CoV-2 infection with a possible positive impact on clinical outcome.

Vitamin D and COVID-19 severity and related mortality: a prospective study in Italy.

BACKGROUND: Vitamin D deficiency has been suggested to favor a poorer outcome of Coronavirus disease-19 (COVID-19). We aimed to assess if 25-hydroxyvitamin-D (25OHD) levels are associated with interleukin 6 (IL-6) levels and with disease severity and mortality in COVID-19. METHODS: We prospectively studied 103 in-patients admitted to a Northern-Italian hospital (age 66.1 ± 14.1 years, 70 males) for severely-symptomatic COVID-19. Fifty-two subjects with SARS-CoV-2 infection but mild COVID-19 symptoms (mildly-symptomatic COVID-19 patients) and 206 subjects without SARS-CoV-2 infection were controls. We measured 25OHD and IL-6 levels at admission and focused on respiratory outcome during hospitalization. RESULTS: Severely-symptomatic COVID-19 patients had lower 25OHD levels (18.2 ± 11.4 ng/mL) than mildly-symptomatic COVID-19 patients and non-SARS-CoV-2-infected controls (30.3 ± 8.5 ng/mL and 25.4 ± 9.4 ng/mL, respectively, p < 0.0001 for both comparisons). 25OHD and IL-6 levels were respectively lower and higher in severely-symptomatic COVID-19 patients admitted to intensive care Unit [(ICU), 14.4 ± 8.6 ng/mL and 43.0 (19.0-56.0) pg/mL, respectively], than in those not requiring ICU admission [22.4 ± 1.4 ng/mL, p = 0.0001 and 16.0 (8.0-32.0) pg/mL, p = 0.0002, respectively]. Similar differences were found when comparing COVID-19 patients who died in hospital [13.2 ± 6.4 ng/mL and 45.0 (28.0-99.0) pg/mL] with survivors [19.3 ± 12.0 ng/mL, p = 0.035 and 21.0 (10.5-45.9) pg/mL, p = 0.018, respectively). 25OHD levels inversely correlated with: i) IL-6 levels (ρ - 0.284, p = 0.004); ii) the subsequent need of the ICU admission [relative risk, RR 0.99, 95% confidence interval (95%CI) 0.98-1.00, p = 0.011] regardless of age, gender, presence of at least 1 comorbidity among obesity, diabetes, arterial hypertension, creatinine, IL-6 and lactate dehydrogenase levels, neutrophil cells, lymphocytes and platelets count; iii) mortality (RR 0.97, 95%CI, 0.95-0.99, p = 0.011) regardless of age, gender, presence of diabetes, IL-6 and C-reactive protein and lactate dehydrogenase levels, neutrophil cells, lymphocytes and platelets count. CONCLUSION: In our COVID-19 patients, low 25OHD levels were inversely correlated with high IL-6 levels and were independent predictors of COVID-19 severity and mortality.

Challenging diagnosis of resistance to thyroid hormone in a patient with COVID-19, pituitary microadenoma and unusual response to octreotide long-acting release test.

Summary: The resistance to thyroid hormone syndrome (RTHß) occurs uncommonly and requires a high level of clinical suspicion and specific investigations to reach a precise diagnosis and to avoid unnecessary and potentially harmful therapies. We report a case of a young male patient referred to our unit for SARS-CoV-2 infection and atrial fibrillation with elevated thyroid hormones and non-suppressed thyroid-stimulating hormone (TSH), for which antithyroid therapy was prescribed. A mood disorder was reported in the medical history. The family history was unknown as the patient was adopted. Thyroid-specific antibodies were undetectable, and thyroid ultrasound revealed a normal thyroid gland without nodules. After the resolution of SARS-CoV-2 infection, the diagnostic workup continued, and the pituitary MRI revealed a small area ascribable to a microadenoma. Due to atrial fibrillation, the execution of the T3 test was contraindicated. The octreotide long-acting release (LAR) test showed an initial reduction of free thyroid hormones levels at first administration, which was consistent with the presence of a TSH-secreting pituitary tumour, although an escape from the response was observed after the following two injections of octreotide LAR. Indeed, the genetic investigation revealed a variant in heterozygosity of the THRß gene (Pro453Ser), thus leading to an RTHß diagnosis, and, therefore, medical treatment with triiodothyroacetic acid was initiated. After 2 years from the SARS-CoV-2 infection, the patient continues the follow-up at our outpatient clinic, and no other medical interventions are needed. Learning points: RTHß is a rare genetic syndrome characterised by discrepant thyroid function tests and by a dissociation between the observed hormone levels and the expected patient signs and symptoms. Features of thyroid hormone deficiency in TR-ß dependent tissues (pituitary gland, hypothalamus, liver and neurosensitive epithelia), as well as thyroid hormone excess in TR-α-dependent tissues (heart, bone, skeletal muscle and brain), may coexist in the same individual. Clinical pictures can be different even when the same variant occurs, suggesting that other genetic and/or epigenetic factors may play a role in determining the patient's phenotype. Differentiating RTHß from a TSH-secreting pituitary tumour is very difficult, especially when a concomitant pituitary adenoma is detected during diagnostic workup. The injection of long-acting somatostatin analogues can help differentiate the two conditions, but it is important to detect any interference in the dosage of thyroid hormones to avoid an incorrect diagnosis. Genetic testing is fundamental to prevent unnecessary and potentially harmful therapies. Medical treatment with triiodothyroacetic acid was demonstrated to be effective in reducing thyroid hormone excess and controlling symptoms.

Increased cardiovascular morbidity and reduced life expectancy in a large Italian cohort of patients with resistance to thyroid hormone ß (RTHß).

OBJECTIVE: Decreased survival and higher cardiovascular morbidity have been recently reported in a UK cohort of 61 RTHß patients, but there is no evidence from other countries. DESIGN: Retrospective cohort study from an historical group of 284 Italian RTHß patients, diagnosed between 1984 and 2023. METHODS: We collected data on diagnosis of 284 cases and longitudinal data of 249 RTHß who carried heterozygous pathogenic variants in the THRB gene. We studied how thyroid function and recognized risk factors for cardiovascular disease, such as hypertension and diabetes, affected overall mortality and major cardiovascular events. RESULTS: The cumulative prevalence of sinus/supraventricular tachycardia and atrial fibrillation was 40% and 18%, respectively. FT4 values 57% higher than the upper limit of normal were associated with premature cardiovascular manifestations. Major cardiovascular events (MACEs) occurred in RTHß patients at a median age (IQR) of 59.4 years (50.4-66.4) and early mortality resulted in a mean of 11 years of life lost. While at univariable analysis hypertension, dyslipidemia, high fasting glucose/diabetes were also associated with MACEs, at multivariable analysis only age at diagnosis, increased fT4 levels, and male gender remained significantly associated with MACEs and age at diagnosis and higher fT4 levels with mortality. Previous thyroidectomy or radioiodine therapy had no statistically significant effect in the prevention of major cardiovascular events or all-cause mortality. CONCLUSIONS: These data should raise the general awareness on the cardiovascular risk and prompt a proactive cardiovascular monitoring in RTHß, especially in men and those with fT4 levels above 30 pmol/L.

A quantitative method for assessing the degree of axial proptosis in relation to orbital tissue involvement in Graves' orbitopathy.

PURPOSE: To define a method of quantifying axial proptosis in patients with Graves' orbitopathy (GO) and to validate a score that correlates with the orbital involvement and helps determine the degree of proptosis correction for elective orbital decompression. DESIGN: Retrospective, case series. PARTICIPANTS: The study included 50 patients (group A) and 29 control subjects who underwent orbital computed tomography (CT). The method was then validated in another group of 21 patients with GO (group B). METHODS: The orbital area (OA) was measured manually on the central axial section of the CT scan at a level where the lens is visualized. The OA intersects the projection of the globe and delimitates the chord of an arch (globe chord [OC]). The area of the circular sector under the chord (CA) represents the portion of the globe within the orbit. MAIN OUTCOME MEASURES: A CA-to-OA ratio was calculated to reduce the error due to variability of the measurements and to perform correlations with some of the clinical parameters of GO. RESULTS: Measurement error was low (<2%). We did not observe significant differences in the mean OA of patients with GO (783.6 ± 12.1 mm(2)) and controls (758.5 ± 20.4 mm(2); P = not significant). The OC value in patients with GO was 130.2 ± 11.5 mm(2), significantly lower than in controls (281.8 ± 9.7 mm(2); P<0.0001). The CA-to-OA ratio also was lower in patients with GO than in controls (0.16 ± 0.01 vs. 0.38 ± 0.01; P<0.0001). A significant correlation was found in patients with GO between the CA-to-OA ratio and proptosis (P<0.001), lid fissure (P = 0.004), and intraocular pressure (P<0.001). In group B, the CA-to-OA ratio was 0.18 ± 0.02, significantly different from that of controls (P<0.0001) and inversely correlated with proptosis (P<0.0001) and lid fissure (P<0.045). CONCLUSIONS: By measuring the CA-to-OA ratio, we were able to quantify the degree of axial proptosis in patients with GO. The significant correlation of CA/OA with some orbital parameters confirms that this parameter also may be used as a measure of orbital involvement in GO. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Factitious thyrotoxicosis and thyroid hormone misuse or abuse.

Factitious thyrotoxicosis (FTT) is a common form of thyroid hormone (TH) abuse involving voluntary but concealed intake of an excessive amount of TH. In most cases, FTT seeks to improve body composition with a decrease in body fat and weight while maintaining apparent fitness. It is frequent in Munchausen syndrome, to attract attention for care. It can involve excessive intake either of thyroxine (T4) or of thyroid extracts or liothyronine (T3). In addition, several dietary supplements available on-line were shown to contain clinically relevant amounts of T4 and T3. TH abuse also occurs in elite athletes and bodybuilders, to reach the appropriate weight and prioritize fat loss. Diagnosis should be suspected whenever the typical features of hyperthyroidism or endogenous thyrotoxicosis are not present, as prolonged overlooked TH abuse can lead to severe consequences, including life-threatening events.

Unusual causes of hyperthyrotropinemia and differential diagnosis of primary hypothyroidism: a revised diagnostic flowchart.

The clinical consequences of primary hypothyroidism include cardiovascular morbidity, increased mortality, and poor quality of life; therefore guidelines endorsed by several Scientific Societies recommend measuring circulating thyroid-stimulating hormone (TSH) in patients at risk. The assessment of serum TSH levels is also deemed to be the most robust and accurate biomarker during the management of replacement therapy in patients with a previous diagnosis of primary hypothyroidism. In line with a reflex TSH laboratory strategy, free thyroxine is measured only if the TSH falls outside specific cutoffs, in order to streamline investigations and save unjustified costs. This serum TSH-based approach to both diagnosis and monitoring has been widely accepted by several national and local health services; nevertheless, false-negative or -positive testing may occur, leading to inappropriate management or treatment. This review aims to describe several infrequent causes of increased circulating TSH, including analytical interferences, resistance to TSH, consumptive hypothyroidism, and refractoriness to levothyroxine replacement treatment. We propose a clinical flowchart to aid correct recognition of these various conditions, which represent important potential pitfalls in the diagnosis and treatment of primary hypothyroidism.

Increased loss of the Y chromosome in peripheral blood cells in male patients with autoimmune thyroiditis.

Multiple mechanisms have been proposed to explain the peculiar distribution of autoimmune thyroiditis (AIT) among women and men. Most attention has been focused on the detection of the role of estrogens and the X chromosome. Specifically, a potential role for X haploinsufficiency has been proposed in the female patient population and an association with the disease has been confirmed. Our knowledge of the etiopathogenesis of autoimmunity in male patients remains, however, limited. Next to the possible role of androgens and their imbalances, the Y chromosome appears as a potential candidate for influence of the immune function in men. Herein we analyzed a population of male patients with AIT (n=31) and healthy controls (n=88) to define a potential association of disease and the loss of the Y chromosome. Y chromosome loss increases in AIT compared to unaffected subjects; these phenomenon increases with aging as expected, however, the degree of loss is significantly increased in the patient population compared to the healthy controls. We were, thus, able to confirm the existence of an analogous mechanism in the male population to previously identified X haploinsufficiency in female patients with AIT. We propose that this commonality might represent a relevant feature in the etiopathogenesis of AIT that should be further investigated.

Tissue sensitivity to thyroid hormones may change over time.

INTRODUCTION: Patients with congenital hypothyroidism (CH) may transiently show a certain degree of pituitary resistance to levothyroxine (LT4) which, however, normalizes subsequently. However, in some individuals, thyroid-stimulating hormone (TSH) fails to normalize despite adequate LT4 treatment. METHODS: Nine patients with CH followed in three Academic Centre who developed over time resistance to thyroid hormones underwent extensive biochemical and genetic analyses. These latter were performed by Sanger sequence or targeted next-generation sequencing technique including a panel of candidate genes involved in thyroid hormone actions and congenital hypothyroidism (CH): THRA, THRB, DIO1, DIO2, SLC16A2, SECISBP2, DUOX2, DUOXA2, FOXE1, GLIS3, IYD, JAG1, NKX2-1, NKX2- 5, PAX8, SLC26A4, SLC5A5, TG, TPO, TSHR. RESULTS: All patients displayed a normal sensitivity to thyroid hormone (TH) in the first years of life but developed variable degrees of resistance to LT4 treatment at later stages. In all cases, TSH normalized only in the presence of high free thyroxine levels. Tri-iodothyronine suppression test followed by thyrotrophin-releasing hormone stimulation was performed in two cases and was compatible with central resistance to THs. This biochemical feature was present independently on the cause of CH, being observed either in patients with an ectopic (n = 2) or eutopic gland (n = 3) or in case of athyreosis (n = 1). None of the patients had genetic variants in genes involved in the regulation of TH actions, while in two cases, we found two double heterozygous missense variants in TSHR and GLIS3 or in DUOX2 and SLC26A4 genes, respectively. CONCLUSIONS: We report CH patients who showed an acquired and unexplainable pituitary refractoriness to TH action.

Impact of thyroid function screening in a large cohort of patients admitted to an emergency department.

BACKGROUND: Thyroid dysfunctions are highly prevalent and can worsen underlying cardiopathies, but despite that the routine screening of thyroid function in the Emergency Department (ED) setting is not generally recommended. OBJECTIVE: To understand if staff training and implementation of rapid TSH screening (rTSH) could improve the management of patients arrived in the ED. Specifically, we aimed at evaluating the prevalence of undiagnosed thyroid diseases among ED patients; the effects of educational meetings in the clinical decision-making process; the usefulness of rTSH, in terms of variation of either the clinical work out or the existing treatment. DESIGN: Retrospective case-control study of 9227 patients managed in the ED of an academic institution. rTSH was routinely available for all patients, who were divided into rTSH-YES and rTSH-NO groups. RESULTS: We included 4243 and 4984  patients in the rTSH-YES and rTSH-NO group, respectively. Trained personnel uncovered a high prevalence of undiagnosed thyroid dysfunction (7%). The diagnosis in the ED of heart failure, history of thyroid diseases, contrast media/amiodarone administration and female gender were independently associated with an increased likelihood to have thyroid dysfunction. The rTSH improved the clinical outcome by (a) appropriate treatment of an underlying clinical condition causing ED entrance, (b) appropriate prophylaxis in patients requiring contrast media, (c) uncovering incorrect treatments, with 60% of patients on levothyroxine requiring a dose reduction. CONCLUSIONS: The rTSH in the ED revealed a high prevalence of untreated thyroid disorders with a major impact on following interventions. The training of a multidisciplinary team is crucial in driving the correct decision-making process.

Association of COVID-19 mortality with serum selenium, zinc and copper: Six observational studies across Europe.

Introduction: Certain trace elements are essential for life and affect immune system function, and their intake varies by region and population. Alterations in serum Se, Zn and Cu have been associated with COVID-19 mortality risk. We tested the hypothesis that a disease-specific decline occurs and correlates with mortality risk in different countries in Europe. Methods: Serum samples from 551 COVID-19 patients (including 87 non-survivors) who had participated in observational studies in Europe (Belgium, France, Germany, Ireland, Italy, and Poland) were analyzed for trace elements by total reflection X-ray fluorescence. A subset (n=2069) of the European EPIC study served as reference. Analyses were performed blinded to clinical data in one analytical laboratory. Results: Median levels of Se and Zn were lower than in EPIC, except for Zn in Italy. Non-survivors consistently had lower Se and Zn concentrations than survivors and displayed an elevated Cu/Zn ratio. Restricted cubic spline regression models revealed an inverse nonlinear association between Se or Zn and death, and a positive association between Cu/Zn ratio and death. With respect to patient age and sex, Se showed the highest predictive value for death (AUC=0.816), compared with Zn (0.782) or Cu (0.769). Discussion: The data support the potential relevance of a decrease in serum Se and Zn for survival in COVID-19 across Europe. The observational study design cannot account for residual confounding and reverse causation, but supports the need for intervention trials in COVID-19 patients with severe Se and Zn deficiency to test the potential benefit of correcting their deficits for survival and convalescence.

The spectrum of thyroid function tests during hospitalization for SARS COV-2 infection.

OBJECTIVE: Alterations in thyroid function tests (TFTs) have been recorded during SARS-CoV-2 infection as associated to either a destructive thyroiditis or a non-thyroidal illness. METHODS: We studied 144 consecutive COVID-19 patients admitted to a single center in intensive or subintensive care units. Those with previous thyroid dysfunctions or taking interfering drugs were excluded. Differently from previous reports, TSH, FT3, FT4, thyroglobulin (Tg), anti-Tg autoantibodies (TgAb) were measured at baseline and every 3-7 days. C-reacting protein (CRP), cortisol and IL-6 were also assayed. RESULTS: The majority of patients had a normal TSH at admission, usually with normal FT4 and FT3. Low TSH levels were found either at admission or during hospitalization in 39% of patients, associated with low FT3 in half of the cases. FT4 and Tg levels were normal, and TgAb-negative. TSH and FT3 were invariably restored at the time of discharge in survivors, whereas were permanently low in most deceased cases, but only FT3 levels were predictors of mortality. Cortisol, CRP and IL-6 levels were higher in patients with low TSH and FT3 levels. CONCLUSIONS: Almost half of our COVID-19 patients without interfering drugs had normal TFTs both at admission and during follow-up. In this series, the transient finding of low TSH with normal FT4 and low FT3 levels, inversely correlated with CRP, cortisol and IL-6 and associated with normal Tg levels, is likely due to the cytokine storm induced by SARS-Cov-2 with a direct or mediated impact on TSH secretion and deiodinase activity, and likely not to a destructive thyroiditis.

A rare mutation of thyroid hormone receptor beta gene in thyroid hormone resistance syndrome.

SUMMARY: Resistance to thyroid hormone (RTH) is a rare hereditary syndrome with impaired sensitivity to thyroid hormones (TH) and reduced intracellular action of triiodothyronine (T3) caused by genetic variants of TH receptor beta (TRB) or alpha (TRA). RTH type beta (RTHß) due to dominant negative variants in the TRB gene usually occurs with persistent elevation of circulating free TH, non-suppressed serum TSH levels responding to a thyrotropin-releasing hormone (TRH) test, an absence of typical symptoms of hyperthyroidism and goiter. Here, we present a rare variant in the TRB gene reported for the first time in an Italian patient with generalized RTHß syndrome. The patient showed elevated TH, with non-suppressed TSH levels and underwent thyroid surgery two different times for multinodular goiter. The genetic test showed a heterozygous mutation in exon 9 of the TRB gene resulting in the replacement of threonine (ACG) with methionine (ATG) at codon 310 (p.M310T). RTHß syndrome should be considered in patients with elevated TH, non-suppressed TSH levels and goiter. LEARNING POINTS: Resistance to thyroid hormone (RTH) is a rare autosomal dominant hereditary syndrome with impaired tissue responsiveness to thyroid hormones (TH). Diagnosis of RTH is usually based on the clinical finding of discrepant thyroid function tests and confirmed by a genetic test. RTH is a rare condition that must be considered for the management of patients with goiter, elevation of TH and non-suppressed serum TSH levels in order to avoid unnecessary treatments.

The relationship between liver histology and thyroid function tests in patients with non-alcoholic fatty liver disease (NAFLD).

BACKGROUND: Data on the role of hypothyroidism in the pathogenesis of non-alcoholic fatty liver disease (NAFLD) and liver fibrosis are conflicting, although selective Thyroid Hormone Receptor (THR)-ß agonists have been identified as potential therapy in patients with non-alcoholic steatohepatitis (NASH). Therefore, we investigated the association between hypothyroidism and NAFLD histological features potentially associated with progressive liver disease. METHODS: Between 2014 and 2016, consecutive patients with histologically proven NAFLD and frozen serum available for thyroid function tests assessment were included. NAFLD was staged according to the NAFLD Activity Score (NAS), and fibrosis according to Kleiner. NASH was defined as NAS ≥4, significant fibrosis as F2-F4 and significant steatosis as S2-S3. Thyroid function tests (TFT; TSH, FT3, FT4, rT3), TPO-Ab and Tg-Ab were also assessed. RESULTS: Fifty-two patients were analyzed: median age 54 years, 58% females, LSM 7.8 kPa, 27% diabetics, 14% hypothyroid. At histology, NASH was present in 21 (40%), F2-F4 in 28 (54%) and S2-S3 in 30 (58%) patients. Rates of hypothyroidism were similar independently of the presence of NASH (p = 0.11), significant fibrosis (p = 0.21) or steatosis (p = 0.75). However, hypothyroid patients displayed a higher NAS (p = 0.02) and NASH (p = 0.06) prevalence. At multivariate analysis, TFT were not independently associated with histology. CONCLUSION: Hypothyroidism was highly prevalent in NAFLD patients, and was associated with increased NAFLD activity, but not with fibrosis and steatosis severity. Thus, thyroid dysfunction might play a direct and/or indirect in the pathogenesis of NAFLD and NASH.

Therapy With Different Dose Regimens of Rituximab in Patients With Active Moderate-To-Severe Graves' Orbitopathy.

Background: Immunosuppressive therapy of Graves' orbitopathy (GO) is indicated during the active phase of disease. Intravenous steroids (IVGC) are effective in about 70% of patients, although unresponsiveness or relapse are observed. In previous studies, rituximab (RTX) has been shown to be effective in inactivating moderate-to-severe GO when used early in the disease, but its optimal dosage has never been studied in randomized clinical trials. Aim of this study was to compare the efficacy and safety of different doses of RTX, based on a post-hoc analysis of two open label studies and one prospective trial randomized to IVGC. Methods: of 40 patients (35 women, 5 men), with active moderate-to-severe GO treated with RTX, 14 received a single dose of 100 mg (Group 1), 15 a single dose of 500 mg (Group 2) and 11 two 1000 mg doses, administered one week apart (Group 3). Thyroid function, TSH-receptor antibodies (TRAb) and peripheral CD19+ cells were measured. Primary endpoint was disease inactivation, measured as a decrease of the Clinical Activity Score (CAS) of at least two points. Secondary endpoints were improvement of proptosis, diplopia, quality of life and safety. Results: Baseline CAS decreased significantly in all groups (P<0.0001), independently of GO duration or whether patients had newly occurring or relapsing GO after IVGC. Proptosis did not significantly change. There was an inverse correlation between the Gorman score for diplopia and RTX dose (P<0.01). The appearance score of the GO-QoL improved in Group 1 (P=0.015), and the visual function score, in Group 2 (P=0.04). A reduction of serum TRAb was observed in Group 1 (P=0.002) and Group 2 (P<0.0002), but not in Group 3. CD19+ cell decreased in all groups (P<0.01), independently of the dose. Conclusions: We studied the optimal dosage of RTX in the treatment of active moderate-to-severe GO. In this analysis, we considered the efficacy of RTX in inactivating GO, in changing its natural course, its effect on disease severity and on the patients' quality of life. Based on our clinical findings, and balancing the cost of therapy, a single 500 mg dose regimen is suggested in the majority of patients.

Clinical Consequences of Variable Results in the Measurement of Free Thyroid Hormones: Unusual Presentation of a Family with a Novel Variant in the THRB Gene Causing Resistance to Thyroid Hormone Syndrome.

INTRODUCTION: Resistance to thyroid hormone ß (RTHß) is an inherited syndrome caused by dominant negative variants in the THRB gene (NM_000461.5). The clinical picture of RTHß is variable, and patients harboring the same variant may display different degrees of disease severity. CASE PRESENTATION: A 30-year-old man presented with thyrotoxicosis and central hyperthyroidism and was found to have a novel variant in the exon 10 of THRB gene (c.C1282G, p.L428V), located within the third hot spot region of the C-terminal of the receptor. Surprisingly, the same variant was found in two other relatives with an apparent normal thyroid function at initial screening. After exclusion of a TSH-secreting adenoma and serum interference in the proband, and the finding that exogenous levothyroxine failed to suppress the TSH in the brother affected by nodular goiter, relatives' thyroid function tests (TFTs) were reassessed with additional analytical method revealing biochemical features consistent with RTHß in all carriers of the p.L428V variant. Functional studies showed a slightly impaired in vitro transcriptional activity of p.L428V. Interestingly' the expression of the human p.L428V thyroid hormone receptor beta in the zebrafish embryo background generated a phenotype consistent with RTHß. CONCLUSION: Variable results of TFTs on some immunoassays can be a cause of RTHß diagnostic delay, but the genotype-phenotype correlation in this family and functional studies support p.L428V as a novel THRB variant expanding the spectrum of gene variants causing RTHß. In vivo, rather than in vitro, functional assays may be required to demonstrate the dominant negative action of THRB variants.

Quantification of Global Ocular Motility Impairment in Graves' Orbitopathy by Measuring Eye Muscle Ductions.

Background: The overall changes of ocular motility in Graves' orbitopathy (GO) are not easily quantifiable with the methods currently available, especially in clinical studies. The aim of the present study was to calculate parameters that quantify the changes of ocular motility in GO in relation to the Gorman score for diplopia. Methods: We studied 100 GO patients (Group 1) and 100 controls (Group 2). We also included 30 patients treated with intravenous methylprednisolone (iv-MP), assessed at baseline and after 12 and 24 weeks (Group 3), and 66 patients submitted to squint surgery, assessed at baseline and after 12 weeks (Group 4). Ocular ductions were measured in four gaze directions by a perimeter arc and were used to calculate a total motility score (TMS) as the sum of ductions in each direction; a biocular TMS (b-TMS) as the sum of the TMS of two eyes; and an asymmetry ratio (AR) as the sum of the differences of the corresponding ductions between the two fellow eyes divided by the mean difference found in controls. Quality of life was accessed by a specific questionnaire (Graves' orbitopathy quality of life [GO-QoL] questionnaire). Results: TMS and b-TMS were lower, while AR was higher, in Group 1 compared with controls (p < 0.001). In Group 1, TMS and b-TMS were inversely correlated with the Gorman score (p < 0.001) and AR was higher in patients with constant diplopia compared with the others (p < 0.001). In Group 3, TMS and b-TMS increased after treatment in responders to iv-MP (p < 0.001). In Group 4, TMS and b-TMS improved in all patients after surgery (p < 0.01), while AR and GO-QoL score improved only in those without residual constant diplopia (p < 0.001). Conclusion: We describe a quantitative method to assess eye motility dysfunction in any stage of GO to be used as an outcome measure in clinical studies.

Efficacy Profile and Safety of Very Low-Dose Rituximab in Patients with Graves' Orbitopathy.

Background: Rituximab (RTX), a chimeric human-murine anti-CD20 monoclonal antibody, has been used for treatment of active moderate-severe Graves' orbitopathy (GO) since 2004 as second-line therapy in patients unresponsive to intravenous steroids. We conducted an open-label prospective study (EUDRACT 2012-001980-53) in which patients were treated with a single infusion of only 100 mg RTX to analyze the efficacy and safety of this low dose. Methods: Seventeen patients, of whom nine had disease that was unresponsive to intravenous methylprednisolone and eight with newly diagnosed GO, were enrolled. Disease activity was assessed with the clinical activity score (CAS) and severity with a composite ophthalmic score. Long-term surgical treatment and quality of life were also assessed, as well as treatment-related adverse events. Results: Mean baseline CAS was 4.56 ± 0.96 and decreased to 1.25 ± 1.14 at 24 weeks (p = 0.001). Disease inactivation occurred within 24 weeks in >90% of patients and was unrelated to disease duration. Severity improved in about 60% of patients, with no relapses. All patients showed peripheral depletion of CD20+ and CD19+ cells at the end of RTX infusion (60 minutes). Two patients required surgical orbital decompression because of optic neuropathy (ON). Among adverse events observed, there was one patient who developed a cytokine release syndrome. Conclusions: A dose of 100 mg RTX is effective in patients with active moderate-severe GO. Low doses are better tolerated, expose patients to immune suppression for a shorter period of time, and are extremely cost effective, compared with higher doses. This dose, consistently with all other immunosuppressants, does not prevent the progression of GO to dysthyroid ON.