COVID-19-related thyroiditis: A novel disease entity?

The literature on COVID-19-related thyroid complications has accumulated over the past year or so as the pandemic has accelerated throughout the world. In particular, several recent case reports have been published describing a possible correlation between COVID-19 disease and subacute thyroiditis (SAT). In this review, we briefly present one of our own patients and review the current published literature in this area up to January 2021, including analyses of major series of thyroid function tests in patients with significant COVID-19 infection. We conclude that while the great majority of patients with severe COVID-19 infection may show manifestations of the sick euthyroid syndrome, clinicians should be aware of the possibility of SAT, especially in the early weeks and months following even mild COVID-19 infection.

Potential Interaction Between SARS-CoV-2 and Thyroid: A Review.

The novel coronavirus disease 2019 (COVID-19) produced by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is sweeping the world in a very short time. Although much has been learned about the clinical course, prognostic inflammatory markers, and disease complications of COVID-19, the potential interaction between SARS-CoV-2 and the thyroid is poorly understood. In contrast to SARS-CoV-1, limited available evidence indicates there is no pathological evidence of thyroid injury caused by SARS-CoV-2. However, subacute thyroiditis caused by SARS-CoV-2 has been reported for the first time. Thyroid dysfunction is common in patients with COVID-19 infection. By contrast, certain thyroid diseases may have a negative impact on the prevention and control of COVID-19. In addition, some anti-COVID-19 agents may cause thyroid injury or affect its metabolism. COVID-19 and thyroid disease may mutually aggravate the disease burden. Patients with SARS-CoV-2 infection should not ignore the effect on thyroid function, especially when there are obvious related symptoms. In addition, patients with thyroid diseases should follow specific management principles during the epidemic period.

Uncommon Association Between Diabetic Ketoacidosis, Thyrotoxicosis, Cutaneous Abscess and Acute Pericarditis in an Immunocompetent Patient: A Single Case Report and Literature Review.

INTRODUCTION: The typical factors precipitating diabetic ketoacidosis (DKA) include infections (30%), cessation of antidiabetic medication (20%), and a new diagnosis of diabetes (25%). The etiology remains unknown in 25% of cases. Less frequent causes cited in the literature include severe thyrotoxicosis and, infrequently, pericarditis. Few publications have described the role of human T lymphotropic virus type 1 (HTLV-1) in endocrine and metabolic disorders. Based on a clinical case associated with several endocrine and metabolic disorders, we suggest a potential role for HTLV-1, an endemic virus in the Amazonian area, and review the literature concerning the role of this virus in thyroiditis, pericarditis and diabetes mellitus. CASE REPORT: A fifty-year-old Surinamese woman without any medical history was admitted for diabetic ketoacidosis. No specific anti-pancreatic autoimmunity was observed, and the C-peptide level was low, indicating atypical type-1 diabetes mellitus. DKA was associated with thyrotoxicosis in the context of thyroiditis and complicated by nonbacterial pericarditis and a Staphylococcus aureus subcutaneous abscess. The patient was infected with HTLV-1. CONCLUSION: To our knowledge, this uncommon association is described for the first time. Few studies have analyzed the implications of HTLV-1 infection in thyroiditis and diabetes mellitus. We did not find any reports describing the association of pericarditis with HTLV-1 infection. Additional studies are necessary to understand the role of HTLV-1 in endocrine and cardiac disorders.

Association of active human herpesvirus-6 (HHV-6) infection with autoimmune thyroid gland diseases.

OBJECTIVES: Viral infections frequently have been cited as important environmental factors implicated in the onset of autoimmune thyroiditis (AIT). The aim of this study was to determine the involvement of HHV-6 infection in the development of autoimmune thyroiditis. METHODS: This study included 45 patients (42 female and 3 male; median age 47.00 IQR 38.50-57.00) with histologically, laboratory, and clinically confirmed autoimmune thyroiditis, as well as 30 autopsied subjects (26 female and 4 male; median age 58.50, IQR 51.50-67.00) without thyroid pathologies and 30 healthy blood donors (25 female and 5 male; median age 33.50, IQR 27.75-44.25) as controls. Results were obtained by applying molecular virology and immunohistochemistry techniques. RESULTS: The presence of persistent HHV-6 infection in AIT patients was significantly higher (p 0.0058) than in the control group (44/45 (98%) vs. 23/30 (77%), respectively). Also, a significantly higher frequency of HHV-6 activation marker (U79/80 mRNA) was found in patients' thyroid gland tissue samples with AIT in comparison with the control group (18/44 (41%) vs. 1/17 (6%), respectively; p 0.0118). The median HHV-6 load was found to be higher in patients with active viral infection than in patients without it (2147, IQR 971-4188 vs. 551, IQR 145-1589 copies/1×106 cells; p 0.003). The presence of HHV-6 antigen expression was demonstrated in intrafollicular cellular clusters and immunohistochemistry indicated thyrocytes in the follicle wall. CONCLUSIONS: These findings provide evidence of strong HHV-6 infection association with AIT development.

Hepatitis C virus infection of a thyroid cell line: implications for pathogenesis of hepatitis C virus and thyroiditis.

BACKGROUND: Autoimmune and non-autoimmune thyroiditis frequently occur in persons with hepatitis C virus (HCV) infection. Treatment with interferon alpha (IFNα) is also associated with significant risk for the development of thyroiditis. To explore HCV-thyroid interactions at a cellular level, we evaluated whether a human thyroid cell line (ML1) could be infected productively with HCV in vitro. METHODS AND RESULTS: ML1 cells showed robust surface expression of the major HCV receptor CD81. Using a highly sensitive, strand-specific reverse transcription polymerase chain reaction assay, positive-sense and negative-sense HCV RNA were detected in ML1 cell lysates at days 3, 7, and 14 postinfection with HCV. HCV core protein was expressed at high levels in ML1 supernatants at days 1, 3, 5, 7, and 14 postinfection. The nonstructural protein NS5A was also detected in ML1 cell lysates by Western blotting. HCV entry into ML1 cells was shown to be dependent on the HCV entry factors CD81 and SR-B1/CLA1, while IFNα inhibited HCV replication in ML1 cells in a dose-dependent manner. Supernatants from HCV-infected ML1 cells were able to infect fresh ML1 cells productively, suggesting that infectious virions could be transferred from infected to naïve thyroid cells in vivo. Additionally, HCV infection of ML1 cells led to increased expression of the pro-inflammatory cytokine IL-8. CONCLUSIONS: For the first time, we have demonstrated that HCV can infect human thyroid cells in vitro. These findings strongly suggest that HCV infection of thyrocytes may play a role in the association between chronic HCV infection and thyroid autoimmunity. Furthermore, the thyroid may serve as an extrahepatic reservoir for HCV viral replication, thus contributing to the persistence of viral infection and to the development of thyroid autoimmunity.

Autoimmune manifestations in viral hepatitis.

Infections by the viruses responsible for hepatitis B, C and D are accompanied by a number of immunopathological manifestations. A link between infection and autoimmunity is particularly well documented for the hepatitis C virus. Immunopathological manifestations range from production of autoantibodies to overt autoimmune disease, including thyroiditis and autoimmune hepatitis, and to immune-complex-mediated disorders, including cryoglobulinaemia, glomerulonephritis and vasculitis. Several of these manifestations improve with successful antiviral treatment, directly incriminating the virus in their pathogenesis. Mechanisms considered responsible for hepatitis virus-related immunopathology, including molecular mimicry, impairment of regulatory T cells and activation of B lymphocytes, will be examined in this review.

Viruses and thyroiditis: an update.

Viral infections are frequently cited as a major environmental factor involved in subacute thyroiditis and autoimmune thyroid diseases This review examines the data related to the role of viruses in the development of thyroiditis. Our research has been focused on human data. We have reviewed virological data for each type of thyroiditis at different levels of evidence; epidemiological data, serological data or research on circulating viruses, direct evidence of thyroid tissue infection. Interpretation of epidemiological and serological data must be cautious as they don't prove that this pathogen is responsible for the disease. However, direct evidence of the presence of viruses or their components in the organ are available for retroviruses (HFV) and mumps in subacute thyroiditis, for retroviruses (HTLV-1, HFV, HIV and SV40) in Graves's disease and for HTLV-1, enterovirus, rubella, mumps virus, HSV, EBV and parvovirus in Hashimoto's thyroiditis. However, it remains to determine whether they are responsible for thyroid diseases or whether they are just innocent bystanders. Further studies are needed to clarify the relationship between viruses and thyroid diseases, in order to develop new strategies for prevention and/or treatment.

[Uveitis associated with thyroïditis in HTLV-1 carriers]. / Uvéite et thyroïdite associée à HTLV-1.

INTRODUCTION: The oncovirus HTLV-1 is aetiologically associated with uveitis and autoimmune thyroiditis in endemic areas. The association of uveitis with autoimmune thyroiditis in HTLV-1 carriers is less common moreover in non-endemic area. EXEGESE: We report two original cases of simultaneous uveitis and autoimmune thyroiditis in HTLV-1 carriers, without other disease due to HTLV-1. The visual outcome was favorable in both cases. CONCLUSION: A significant correlation exists between hyperthyroidism, uveitis and HTLV-1, but still needs to be confirmed. The autoimmune or immune mediated mecanism of HTLV-1 may be involved in the uveitis and the thyroidits.

An unusual form of Riedel's thyroiditis: a case report and review of the literature.

We report the case of a 36-year old woman with a history of long-term fever associated with a biologic inflammatory syndrome that was not corrected by several courses of corticosteroid treatment. The only remarkable result during previous investigations was the presence of a positive Epstein-Barr virus (EBV) serology. Clinical examination revealed an heterogenous thyroid with a nodule on the right lobe. Serum thyrotropin (TSH) concentration was normal. The levels of antiperoxidase antibodies and thyrocalcitonin were normal. Ultrasound examination of the neck showed a 3-cm hypoechogenous nodule in the right lobe of the thyroid. A total thyroidectomy was performed. Histopathologic findings led to the diagnosis of Riedel's thyroiditis. We observed a dramatic improvement after surgery with absence of fever and normalization of inflammatory parameters. The role of EBV infection in the process of this unusual form of Riedel's thyroiditis is discussed.

Extrahepatic manifestations of hepatitis C.

Shortly after the discovery of the hepatitis C virus, it was realized that this infectious agent caused more than just liver disease. A remarkable array of extrahepatic manifestations of hepatitis C has now been described. Many of these associated syndromes implicate the hepatitis C virus as a mediator of autoimmunity or of immune complex formation. These disorders include mixed essential cryoglobulinemia, autoimmune hepatitis, glomerulonephritis, thyroiditis, and possibly Sjogren's syndrome. The hepatitis C virus has also been strongly linked to two skin disorders: prophyria cutanea tarda and lichen planus. Other possible hepatitis-C-associated diseases described in the literature include idiopathic pulmonary fibrosis, IgA deficiency. Mooren's corneal ulcers, Behcet's syndrome, polyarthritis, Guillain-Barre' syndrome, idiopathic thrombocytopenic purpura, and others. A number of these reported diseases have either responded to or been cured by a therapeutic course of alpha interferon. This report discusses the reported extrahepatic manifestations of hepatitis C as of mid-1995.

Sporadic activation of Epstein-Barr virus in thyroid lymphoma.

The causal role of Epstein-Barr virus (EBV) in the development of B-cell lymphoma, especially in immunocompromised individuals, has been suggested. The purpose of the present study was to evaluate an association of EBV with thyroid lymphoma (TL) and chronic lymphocytic thyroiditis (CLTH) which is known to play an important role in the development of TL. Thirty cases with TL and 28 with CLTH were studied for presence or absence of EBV genome in the lesions using the polymerase chain reaction (PCR) and the in situ hybridization method. EBV genomes were detected by PCR in one and two cases with CLTH and TL, respectively. Subtyping of EBV genome was possible in one TL case showing B-type in EBNA-2 coding region. In situ hybridization revealed positive signals in the nucleus of lymphoma cells, which also expressed latent membrane protein-1. The present findings indicate that activation of EBV in TL is not common.