Autoimmune thyroid diseases (AITDs) are chronic autoimmune disorders that cause impaired immunoregulation, leading to specific immune responses against thyroid antigens. Graves’ disease (GD) and ...Hashimoto’s thyroiditis (HT) are the major forms of AITDs. Increasing evidence suggests a possible role of microbiota alterations in the pathogenesis and progression of AITDs. This systematic review was designed to address the following question: “Is microbiota altered in patients with AITDs?” After screening the selected studies using the inclusion and exclusion criteria, 16 studies were included in this review (in accordance with PRISMA statement guidelines). A meta-analysis revealed that patients with HT showed significantly higher values of diversity indices (except for the Simpson index) and that patients with GD showed significant tendencies toward lower values of all assessed indices compared with healthy subjects. However, the latter demonstrated a higher relative abundance of Bacteroidetes and Actinobacteria at the phylum level and thus Prevotella and Bifidobacterium at the genus level, respectively. Thyroid peroxidase antibodies showed the most significant positive and negative correlations between bacterial levels and thyroid functional parameters. In conclusion, significant alterations in the diversity and composition of the intestinal microbiota were observed in both GD and HT patients.
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
analysis of two open label studies and one prospective trial randomized to IVGC.
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.
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.
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.
Hypothyroidism is common throughout the world and readily diagnosed with thyroid function tests. Management should be straightforward but appears not to be the case. Thyroid hormone replacement with ...levothyroxine monotherapy is the standard treatment which is effective in the majority of cases. However, 10–15% of patients established on levothyroxine do not feel their health is entirely restored and some patients prefer the addition of liothyronine. Proponents of liothyronine argue that the ratio of T3 and T4 hormones is substantially altered on T4 monotherapy and therefore both hormones may be needed for optimal health. This remains controversial as clinical trials have not demonstrated superiority of combination therapy (levothyroxine and liothyronine) over levothyroxine monotherapy. There is now a pressing need for further studies and in particular randomized controlled trials in this area. To help design and facilitate dedicated trials and better understand thyroid hormone replacement, this review summarizes the evidence where there is established knowledge and agreement (knowns) and areas where research is lacking (unknowns). Agreements include the extent of dissatisfaction with levothyroxine monotherapy, biases in testing for hypothyroidism and prescribing levothyroxine, as well as variable thresholds for prescribing levothyroxine and challenges in liothyronine dosing. The review will also highlight and summarize the unknowns including the long-term safety profile of liothyronine, and potential biomarkers to identify individuals who might benefit most from combination therapy.
Thyroid stimulating antibodies (TSAB) cause Graves' disease and contribute to Graves' Orbitopathy (GO) pathogenesis. We hypothesise that the presence of TSH binding proteins (truncated
variants (
)) ...and/or nonclassical ligands such as
(
) might provide a mechanism to protect against or exacerbate GO. We analysed primary
orbital preadipocyte-fibroblasts (OF) from GO patients and people free of GO (non-GO). Transcript (QPCR) and protein (western blot) expression levels of
were measured through an adipogenesis differentiation process. Cyclic-AMP production by TSHR activation was studied using luciferase-reporter and RIA assays. After differentiation,
levels in OF from GO were significantly higher than non-GO (
= 0.039), and confirmed in ex vivo analysis of orbital adipose samples. TSHRv western blot revealed a positive signal at 46 kDa in cell lysates and culture media (CM) from non-GO and GO-OF. Cyclic-AMP decreased from basal levels when OF were stimulated with TSH or Monoclonal TSAB (M22) before differentiation protocol, but increased in differentiated cells, and was inversely correlated with the
:
ratio (Spearman correlation: TSH r = -0.55,
= 0.23, M22 r = 0.87,
= 0.03). In the bioassay, TSH/M22 induced luciferase-light was lower in CM from differentiated GO-OF than non-GO, suggesting that secreted TSHRv had neutralised their effects.
transcripts were present but reduced during adipogenesis (
< 0.005) with no difference observed between non-GO and GO.
transcripts were at the limit of detection. Our work demonstrated that
transcripts are expressed as protein, are more abundant in GO than non-GO OF and have the capacity to regulate signalling via the
.
Primary bilateral macronodular adrenal hyperplasia (PBMAH) represents an uncommon cause of endogenous hypercortisolism. Since the first description in 2003 in a French cohort, many papers have been ...published describing families as well as isolated individuals affected with this condition, who were found to harbor a genetic variants in the armadillo-repeat containing 5 (
) gene, a tumor-suppressor gene with a still unknown role in the disease pathogenesis. Studies in rat models suggested a possible link between
damaging variants and the impairment of the cell-mediated immune response, leading to a higher susceptibility to bacterial and viral infections. To our knowledge, we describe the first case of a patient affected by PBMAH with hypogammaglobulinemia and monthly relapsing human herpes simplex viral infections. After the detection of subclinical Cushing's syndrome, a unilateral laparoscopic adrenalectomy was performed. Subsequent genetic analysis of
performed on genomic DNA extracted both from the adrenal tissue and lymphocytes revealed a novel somatic frameshift variant in exon 1 (c.231_265del:p.A77Afs*13) and a novel germline variant in exon 6 (c.2436del: p. C813Vfs*104). After adrenalectomy, we observed a significant improvement of clinical features concerning both hypercortisolism and relapsing viral infections, thus suggesting a possible adjuvant role of hypercortisolism on a genetic-based derangement of the immune system.
Secondary thyroid autoimmunity, especially Graves' disease (GD), frequently develops in patients with multiple sclerosis (MS) following alemtuzumab treatment (ALTZ; anti-CD52). Thyroid eye disease ...(TED) can also develop, and rituximab (RTX; anti-CD20) is a suitable treatment.
A 37-year-old woman with MS developed steroid-resistant active moderate-to-severe TED 3 years after ALTZ, that successfully responded to a single 500 mg dose of i.v. RTX. Before RTX peripheral B-cells were low, and were totally depleted immediately after therapy. Follow-up analysis 4 years post ALTZ and 1 year post RTX showed persistent depletion of B cells, and reduction of T regulatory cells in both peripheral blood and thyroid tissue obtained at thyroidectomy.
RTX therapy successfully inactivated TED in a patient with low B-cell count derived from previous ALTZ treatment. B-cell depletion in both thyroid and peripheral blood was still present 1 year after RTX, indicating a likely cumulative effect of both treatments.
Hyaluronan (HA), an extra-cellular matrix glycosaminoglycan, may play a role in mesenchymal stem cell differentiation to fat but results using murine models and cell lines are conflicting. Our ...previous data, illustrating decreased HA production during human adipogenesis, suggested an inhibitory role. We have investigated the role of HA in adipogenesis and fat accumulation using human primary subcutaneous preadipocyte/fibroblasts (PFs,
= 12) and subjects of varying body mass index (BMI). The impact of HA on peroxisome proliferator-activated receptor gamma (PPARγ) expression was analysed following siRNA knockdown or HA synthase (HAS)1 and HAS2 overexpression. PFs were cultured in complete or adipogenic medium (ADM) with/without 4-methylumbelliferone (4-MU = HA synthesis inhibitor). Adipogenesis was evaluated using oil red O (ORO), counting adipogenic foci, and measurement of a terminal differentiation marker. Modulating HA production by HAS2 knockdown or overexpression increased (16%,
< 0.04) or decreased (30%,
= 0.01) PPARγ transcripts respectively. The inhibition of HA by 4-MU significantly enhanced ADM-induced adipogenesis with 1.52 ± 0.18- (ORO), 4.09 ± 0.63- (foci) and 2.6 ± 0.21-(marker)-fold increases compared with the controls, also increased PPARγ protein expression (40%, (
< 0.04)). In human subjects, circulating HA correlated negatively with BMI and triglycerides (
= -0.396 (
= 0.002),
= -0.269 (
= 0.038), respectively), confirming an inhibitory role of HA in human adipogenesis. Thus, enhancing HA action may provide a therapeutic target in obesity.
Objective: We have previously observed thyroid dysfunction, i.e. atypical thyroiditis (painless thyrotoxicosis associated to non-thyroidal illness syndrome), in patients with ...severe-acute-respiratory-syndrome-coronavirus-2 disease (Covid-19). This study aimed to analyse the evolution of thyroid dysfunction over time. Methods: 183 consecutive patients hospitalised for severe Covid-19 without known thyroid history were studied at hospital admission (baseline). Survivors were offered 12-month longitudinal follow-up including assessment of thyroid function, autoantibodies and ultrasound scan (US). Patients showing US focal hypoechoic areas suggestive of thyroiditis (focal-hypoechogenicity) also underwent thyroid 99mTc or 123I uptake scan. Results: At baseline, after excluding from TSH analysis 63 out of 183 (34%) Covid-19 patients commenced on steroids before hospitalisation, 12 (10%) showed atypical thyroiditis. Follow-up of 75 patients showed normalisation of thyroid function and inflammatory markers, and no increased prevalence of detectable thyroid autoantibodies. Baseline US (available in 65 patients) showed focal-hypoechogenicity in 28% patients, of whom 82% had reduced thyroid 99mTc/123I uptake. The presence of focal-hypoechogenicity was associated with baseline low TSH (p=0.034), high FT4 (p=0.018) and high IL-6 (p=0.016). Focal-hypoechogenicity persisted after 6 and 12 months in 87% and 50% patients, respectively, but reduced in size. After 9 months thyroid 99mTc/123I uptake partially recovered from baseline (+28%), but was still reduced in 67% patients. Conclusions: Severe Covid-19 induces mild transient thyroid dysfunction correlating with disease severity. Focal-hypoechogenicity, associated with baseline high FT4, IL-6 and low TSH, does not seem to be related to thyroid autoimmunity and may persist after one year although decreasing in size. Long-term consequences seem unlikely.
Objective Many cases of subacute thyroiditis (SAT) have been described related to SARS-CoV-2 infection, but no prospective data about follow-up are known. This prospective, longitudinal, 3-year, ...multicentre study aims to explore the clinical peculiarities and outcome of SAT in relation to SARS-CoV-2 infection, ascertained with antibody dosage. Methods All patients receiving SAT diagnosis from November 2020 to May 2022 were enrolled. Data on anamnesis, physical examination, blood tests (TSH, freeT4, freeT3, thyroglobulin, anti-thyroid antibodies, C-reactive protein, erythrocyte sedimentation rate, complete blood count), and thyroid ultrasound were collected. At baseline, the presence of IgG against the SARS-CoV-2 spike protein or nucleocapsid was investigated. Patients were evaluated after 1, 3, 6, and 12 months. Results Sixty-six subjects were enrolled. At baseline, 54 presented with pain, 36 (67%) for at least 15 days. Serum SARS-CoV-2 IgG measurements documented that 7 out of 52 subjects (13.5%) had infection before SAT diagnosis (COVID+). No significant differences between the COVID+ and COVID− groups were found at baseline, except for respiratory symptoms and fever, which were more common in COVID+ ( P = 0.039 and P = 0.021, respectively). Among the 41 subjects who completed follow-up, COVID+ and COVID− did not differ for therapeutic approach to SAT or outcome, all having an improvement in neck pain, inflammation parameters, and ultrasound features. Conclusion This is the first prospective study investigating any difference both at diagnosis and at follow-up between SAT presentation in patients with previous SARS-CoV-2 infection and those without. Our data demonstrate that SARS-CoV-2 does not impact on SAT onset, evolution, and outcome.
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