Coronavirus Disease 2019 and Thyroid Diseases.

Since the outbreak of coronavirus disease 2019 (COVID-19), a number of COVID-19 related thyroid disorders have been reported, including subacute thyroiditis, autoimmune thyroid disease, non-thyroidal illness syndrome and some unexplained thyroid dysfunction. This review aimed to summarize clinical characteristics of COVID-19 related thyroid disorders and to discuss some possible mechanisms.Copyright © 2022, Peking Union Medical College Hospital. All rights reserved.

Subacute thyroiditis associated with COVID-19 affecting health professionals, a case series in high-risk population

Background: Healthcare professionals are more vulnerable to infectious infections, especially ones that are easily transferred, such as COVID-19. Subacute thyroiditis is a self-limiting thyroid gland infection caused by a virus. SARS-CoV-2 infection increases the prevalence of subacute thyroiditis. Objective: This case series addresses the emergence of subacute thyroiditis cases linked to SARS-CoV-2 infection, which is more common in healthcare personnel. Methods: This study analyzed nine COVID-19 cases with neck pain symptoms. The clinical presentation, thyroid markers, ultrasound features of the thyroid gland, and its management were described in this study. Result: There were nine cases included, and seven out of nine were experienced by healthcare professional workers. All of them were patients in the Clinic of Endocrinology Metabolism and Diabetes-Thyroid Center, Dr. Zainoel Abidin Hospital, Banda Aceh, Indonesia, from January to June 2021. Most of them presented with mild to moderate neck pain. All patients had clinical improvement within two weeks to two months after receiving treatments. Conclusion: Subacute thyroiditis is a painful thyroid gland disease characterized by acute inflammation of the thyroid gland, which can arise during or after a viral infection such as COVID-19. This case series emphasizes the importance of physicians awareness that subacute thyroiditis could be one of many clinical spectra of SARS-CoV-2 infection that should not be missed. © 2023, Sanglah General Hospital. All rights reserved.

Subacute Thyroiditis Following Vaccination with COVID-19 mRNA Vaccine

Introduction: Subacute thyroiditis is a self-limiting post-viral inflammatory disorder occurring in 3 phases (hyper-, hypo-, and euthyroidism) Post-vaccine thyroiditis has also been reported, but is rare. Case Description: A 36-year-old Emirati female presented to our clinic with generalized fatigue, mild to moderate vague neck pain, intermittent palpitations, and loss of appetite 2 weeks after receiving her first dose of Pfizer-BioNTech mRNA vaccine against COVID-19. Clinical examination findings and laboratory test results were consistent with subacute thyroiditis. Patient is a mother of 5 healthy children, youngest is breast-fed infant (11 months old). There was no history suggestive of postpartum thyroiditis and no family history of thyroid dysfunction. Physical examination at initial visit showed mild tachycardia, and a normal blood pressure. She weighed 66 kg. Thyroid function tests revealed a suppressed TSH of 0.011 muIU/mL, high Free T4 of >100 pmol/l), and Free T3 FT3 of 29.6 pmol/L. Both TSH receptor antibodies, and Thyroid antibodies (TPO) were negative. Thyroid scintigraphy showed decreased uptake in both lobes. Thyroid ultrasound showed hypoechoic heterogeneous echotexture of the thyroid gland with vascular conglomerate and micro-calcification, along with normal sized reactive lymph nodes at sternal angle. Symptoms aggravated through the next week;patient dropped 3kg of her body weight and her palpitations increased, with a recorded resting heart rate between 120-130 beats/min. TSH decreased to 0.001muIU/mL while FT4 remained high, with an improvement to 90 pmol/L. Subsequently, the patient started to regain weight. Palpitations improved within a month. She developed a biochemically hypothyroid picture followed by clinical and biochemical euthyroidism after one more month. Second dose of the vaccine was uneventful. Last evaluation was 10 months later;TSH, FT3 and FT4 were all in normal range, acute-phase reactants were completely normal and in complete remission. Discussion(s): The exact mechanism for post-vaccination subacute thyroiditis remains unknown, vaccine adjuvants may induce diverse autoimmune and inflammatory reaction. Subacute thyroiditis has rarely been reported with other COVID-19 vaccines contains no Polyethylene glycol (PEG). A possible cross-reactivity between thyroid cell antigens and spike protein of the coronavirus produced by mRNA vaccines might be responsible. Further research is needed to investigate the incidence of subacute thyroiditis in COVID-19 pandemic days.Copyright © 2023

New-Onset Thyroid Eye Disease After COVID-19 Infection in Patient with Graves' Disease Post-Radioactive Iodine Treatment

Introduction: Coronavirus disease 2019 (COVID-19) has been associated with dysregulation of the immune system and abnormal thyroid function. The aim of this novel case report is to inform physicians of the possibility that COVID-19 infection may precipitate thyroid eye disease (TED) in patients with Graves' Disease (GD) even after treatment with radioactive iodine (RAI). Case Description: In this report, we describe a patient with GD treated with RAI who developed TED after COVID-19 infection. The patient was initially diagnosed with GD in 2018. A thyroid uptake scan (I-123) was consistent with GD with moderately elevated uptake. She was initially managed with methimazole and atenolol and was eventually treated with RAI (16.32 millicurie I-131) in February 2021. She had post-ablative hypothyroidism managed with levothyroxine. The patient contracted COVID-19 in January 2022. In February 2022, the patient started experiencing eye irritation, dryness, protrusion of eyes, eyelid swelling, and visual disturbances. Thyroid stimulating hormone (TSH) receptor auto-antibodies (7.33 IU/L, normal < /=1.00 IU/L) and thyroid stimulating immunoglobulin (4.30 IU/L, normal < /=1.00 IU/L) were elevated. TSH was normal (2.180 mIU/L, normal 0.270 - 4.200 mIU/L) on levothyroxine 125 mcg daily. She was later diagnosed with TED. Discussion(s): GD is an autoimmune thyroid disorder related to the presence of TSH receptor-stimulating antibodies and is often associated with ocular symptoms. Activation of an autoimmune response during COVID-19 infection, may induce onset or relapse of GD. A study using the national health insurance service database in South Korea noted an increase in the incidence of subacute thyroiditis in 2020 in association with the COVID-19 pandemic. TED is usually seen in patients with GD. Radioactive iodine is widely used in the treatment of GD and has been associated with development or worsening of TED. There are published cases of TED occurring in patients with GD after receiving COVID-19 vaccine. It is thought that the inflammatory syndrome induced by the adjuvants could induce molecular mimicry, which could trigger TED. In most cases this adverse effect was transient, lasting a few months after treatment. There have been case reports of TED occurring after 3 to 21 days of COVID-19 vaccination in patients with controlled GD. Symptoms improved in 4-8 months. Development of TED in patients with GD who have been treated with RAI typically occurs soon after RAI therapy. For TED to occur in a GD patient 11 months after receiving RAI therapy is unusual. COVID-19 infection appears to have been the trigger for this patient's eye disease. This is highly unusual and has not been published to our knowledge.Copyright © 2023

Subacute THYROiditis Related to SARS-CoV-2 VAccine and Covid-19 (THYROVAC Study): A Multicenter Nationwide Study.

BACKGROUND/AIM: The aims of the study are to compare characteristics of subacute thyroiditis (SAT) related to different aetiologies, and to identify predictors of recurrence of SAT and incident hypothyroidism. METHODS: This nationwide multicenter retrospective cohort study included 53 endocrinology centers in Turkey. The study participants were divided into either coronavirus disease-2019 (COVID-19)-related SAT (Cov-SAT), severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine-related SAT (Vac-SAT), or control SAT (Cont-SAT). RESULTS: Of the 811 patients, 258 (31·8%) were included in the Vac-SAT group, 98 (12·1%) in the Cov-SAT group, and 455 (56·1%) in the Cont-SAT group. No difference was found between the groups with regard to laboratory and imaging findings. The aetiology of SAT was not an independent predictor of recurrence or hypothyroidism. In the entire cohort, steroid therapy requirement and younger age were statistically significant predictors for SAT recurrence. C-reactive protein (CRP) measured during SAT onset, female gender, absence of anti-thyroid peroxidase (TPO) positivity, and absence of steroid therapy were statistically significant predictors of incident (early) hypothyroidism, irrespective of SAT aetiology. On the other hand, probable predictors of established hypothyroidism differed from that of incident hypothyroidism. CONCLUSION: Since there is no difference in terms of follow-up parameters and outcomes, COVID-19- and SARS-CoV-2- vaccine related SATs can be treated and followed up like classical SATs. The recurrence was determined by the younger age and steroid therapy requirement. Steroid therapy independently predict incident hypothyroidism that may sometimes be transient in overall SATs and is also associated with lower risk of established hypothyroidism.

A case report of subacute thyroiditis after inactivated SARS-CoV-2 vaccine.

Subacute thyroiditis is an inflammatory thyroid disorder. It is often triggered following viral infections. Amid the current COVID-19 pandemic, several cases of subacute thyroiditis were reported worldwide related to SARS-CoV-2 infection and vaccines. We report a rare case of subacute thyroiditis possibly related to immunization with inactivated SARS-CoV-2 vaccine Sinopharm BIBP. A 29-year-old previously healthy Sri Lankan woman presented with anterior neck pain, low-grade fever and fatigue appearing 7 days after immunization with the second dose of inactivated SARS-CoV-2 vaccine Sinopharm BIBP. She apparently reported similar symptoms which subsided spontaneously within a few days, following immunization with first dose of vaccine. On examination, she had tenderness over the anterior neck. She was afebrile, not tachycardic and clinically euthyroid. Her inflammatory markers were elevated. An ultrasound scan of the neck demonstrated two low echogenic micronodules of 6 x 3 mm2 and 5 x 3 mm2 and low background thyroid vascularity. Technetium 99 m pertechnetate (Tc - 99 m) thyroidal uptake scan shows reduced thyroidal uptake suggestive of subacute thyroiditis. Thyroid function tests were normal at the time of the assessment. The patient was treated symptomatically with non-steroidal anti-inflammatory drugs. Her neck pain and tenderness resolved gradually. Serial measurements of thyroid functions during follow-up were within normal limits. Inflammatory markers normalized over the course of follow-up. Subacute thyroiditis following COVID-19 vaccination is a rare occurrence. However, due to its mild clinical course, it could very well be underreported. It is a mild and self-limiting illness with transient thyroid dysfunction; thus, it should be emphasized that the benefits of COVID-19 vaccination outweigh any rare and mild side effects reported.

Neck Swelling in a Critically Ill Patient With COVID-19-Related Acute Respiratory Distress Syndrome on Venovenous Extracorporeal Membrane Oxygenation: Consider the Differential.

Neck swelling during venovenous extracorporeal membrane oxygenation (VV-ECMO) usually heralds the development of potentially serious complications, including superior vena cava (SVC) syndrome, hematoma, and/or angioedema. In this case report, we describe a 43-year-old male patient who had received VV-ECMO support for the coronavirus disease 2019 (COVID-19) acute respiratory distress syndrome. During his hospitalization, he developed acute onset of neck swelling after two weeks of VV-ECMO and two days after a tracheostomy. Clinical examination and investigations were performed to exclude ECMO-related SVC syndrome and tracheostomy-related complications. Consequently, it was discovered the patient had developed COVID-19-related subacute thyroiditis with enlargement of both thyroid glands. Conservative management, including the use of continued glucocorticoids, raising the head of the bed, and observing for complications of thyroiditis, was undertaken. Eventually, this patient's neck swelling resolved on its own, and he was eventually decannulated from ECMO several weeks later. Our case report highlights the differential diagnosis of neck swelling during VV-ECMO and considers the evaluation of different etiologies.

Subacute thyroiditis following COVID-19: A systematic review.

Background: Subacute thyroiditis (SAT) is a self-limiting thyroid inflammatory disease occurring specifically after upper respiratory tract infections. Since COVID-19 is a respiratory disease leading to multi-organ involvements, we aimed to systematically review the literature regarding SAT secondary to COVID-19. Methods: We searched Scopus, PubMed/MEDLINE, Cochrane, Web of Science, ProQuest, and LitCovid databases using the terms "subacute thyroiditis" and "COVID-19" and their synonyms from inception to November 3, 2022. We included the original articles of the patients with SAT secondary to COVID-19. Studies reporting SAT secondary to COVID-19 vaccination or SAT symptoms' manifestation before the COVID-19 infection were not included. Results: Totally, 820 articles were retained. Having removed the duplicates, 250 articles remained, out of which 43 articles (40 case reports and three case series) with a total of 100 patients, were eventually selected. The patients aged 18-85 years (Mean: 42.70, SD: 11.85) and 68 (68%) were women. The time from the onset of COVID-19 to the onset of SAT symptoms varied from zero to 168 days (Mean: 28.31, SD: 36.92). The most common symptoms of SAT were neck pain in 69 patients (69%), fever in 54 (54%), fatigue and weakness in 34 (34%), and persistent palpitations in 31 (31%). The most common ultrasonographic findings were hypoechoic regions in 73 (79%), enlarged thyroid in 46 (50%), and changes in thyroid vascularity in 14 (15%). Thirty-one patients (31%) were hospitalized, and 68 (68%) were treated as outpatients. Corticosteroids were the preferred treatment in both the inpatient and outpatient settings (25 inpatients (81%) and 44 outpatients (65%)). Other preferred treatments were nonsteroidal anti-inflammatory drugs (nine inpatients (29%) and 17 outpatients (25%)) and beta-blockers (four inpatients (13%) and seven outpatients (10%)). After a mean duration of 61.59 days (SD: 67.07), 21 patients (23%) developed hypothyroidism and thus, levothyroxine-based treatment was used in six of these patients and the rest of these patients did not receive levothyroxine. Conclusion: SAT secondary to COVID-19 seems to manifest almost similarly to the conventional SAT. However, except for the case reports and case series, lack of studies has limited the quality of the data at hand.

Thyroid autoimmunity and COVID-19

Thyroid autoimmunity manifests mainly as autoimmune Hashimoto's thyroiditis and Graves' disease. Subacute thyroiditis is a postinflammatory or inflammatory thyroid disease. SARS-CoV-2 is a coronavirus, which has caused the recent pandemic. The SARS-CoV-2 disease is a factor leading to autoimmunity. Thyroid disease is a rare manifestation of SARS-CoV-2 infection. Cases of subacute thyroiditis in patients with the Covid-19 infection have been described all over the world. Cases of thyroiditis, hypothyroidism and Graves' disease have been observed following SARS-CoV-2 infection. Vaccination against the SARS-CoV-2 virus has helped to limit the pandemic and is characterized by very few side effects. Cases of subacute thyroiditis and cases of Graves' disease have been found after vaccination against the SARS-CoV-2 virus. In conclusion, SARS-CoV-2 is a coronavirus which has been related to the development of autoimmunity. Autoimmune thyroid disease, in the form of either subacute thyroiditis, autoimmune thyroiditis, and Graves' disease, has been described in patients with the COVID-19 disease. © 2023 Elsevier Inc. All rights reserved.

The scintigraphic diagnosis of subacute thyroiditis in hospitalized patients with acute COVID-19 infection

Introduction: Extrapulmonary manifestations of COVID-19 must not be neglected during the pandemic. Subacute thyroiditis is one of the possible complications people encounter during post-COVID-19 days. Thyroid scintigraphy and radioiodine uptake test help discriminate hyperthyroidism from destructive thyrotoxicosis. Finding a more precise way to diagnose subacute thyroiditis can help in the early detection and treatment of thyroid-related disorders. Method(s): In this cross-sectional study, we evaluated 69 cases of COVID-19. Patients were divided into moderate and severe groups based on their clinical conditions. A thyroid scintigraphy scan was performed on the discharge day. Imaging was done 15-20 minutes after intravenous administration of 3-5 mCi of [99mTc]TcO4-. Scan findings were compared between moderate and severe groups and other participants' demographic and clinical features. Result(s): In 69 patients, according to thyroid scintigraphy, 25 (36%) cases were reported as thyroiditis, and the rest were normal. There was no significant difference between the normal and subacute thyroiditis groups based on age, gender, past medical history, the severity of COVID-19, laboratory values and clinical signs and symptoms. Patients with subacute thyroiditis experienced palpitation and sore throat significantly higher than the normal group (P=0.002 and P=0.009, respectively). Conclusion(s): We conclude that patients admitted due to acute COVID-19 infection experiencing palpitation and sore throat can develop subacute thyroiditis more than others. Whereas the severity of the disease and laboratory testing were not diagnostic in subacute thyroiditis, thyroid scintigraphy may help in early detection.Copyright © 2023 The Authors.

A case of subacute thyroiditis after influenza vaccination

A 40-year-old Japanese woman presented to the outpatient clinic with fever and palpitations 2 days after receiving the influenza vaccine (Influenza HA Vaccine 'KMB') following the second dose of coronavirus disease 2019 (COVID-19) vaccine (COVID-19 vaccine Moderna intramuscular injection). At the first visit, the patient presented with a swollen thyroid gland with mild tenderness, and she was diagnosed with subacute thyroiditis (SAT) based on the presence of thyrotoxicosis (free T3: 5.42 pg/mL;free T4: 2.34 ng/dL;and thyroid-stimulating hormone (TSH): <0.01 muIU/mL), a high C-reactive protein level (5.77 mg/dL), a negative TSH receptor antibody, and characteristic ultrasound findings. The patient's human leukocyte antigen types were A2, A11, B35, B51, DR4, and DR1403. Prednisolone (15 mg/day) was given as an initial dose, after which the fever subsided, and the dose was tapered and discontinued after 6 weeks. The patient was thought to have developed SAT due to influenza vaccination. SAT after influenza vaccination may be overlooked. For patients with SAT, it is necessary to obtain information regarding their vaccination history.Copyright © 2023 The authors.

HLA typing of patients who developed subacute thyroiditis and Graves' disease after SARS-CoV-2 vaccination: a case report.

BACKGROUND: Cases of subacute thyroiditis (SAT) after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination have been reported. A human leukocyte antigen (HLA) allele, HLA-B*35, appears to be involved in the pathogenesis of SAT. CASE PRESENTATION: We conducted HLA typing of one patient with SAT and another with both SAT and Graves' disease (GD), which developed after SARS-CoV-2 vaccination. Patient 1, a 58-year-old Japanese man, was inoculated with a SARS-CoV-2 vaccine (BNT162b2; Pfizer, New York, NY, USA). He developed fever (38 °C), cervical pain, palpitations, and fatigue on day 10 after vaccination. Blood chemistry tests revealed thyrotoxicosis and elevated serum C-reactive protein (CRP) and slightly increased serum antithyroid-stimulating antibody (TSAb) levels. Thyroid ultrasonography revealed the characteristic findings of SAT. Patient 2, a 36-year-old Japanese woman, was inoculated twice with a SARS-CoV-2 vaccine (mRNA-1273; Moderna, Cambridge, MA, USA). She developed fever (37.8 °C) and thyroid gland pain on day 3 after the second vaccination. Blood chemistry tests revealed thyrotoxicosis and elevated serum CRP, TSAb, and antithyroid-stimulating hormone receptor antibody levels. Fever and thyroid gland pain persisted. Thyroid ultrasonography revealed the characteristic findings of SAT (i.e., slight swelling and a focal hypoechoic area with decreased blood flow). Prednisolone treatment was effective for SAT. However, thyrotoxicosis causing palpitations relapsed thereafter, for which thyroid scintigraphy with 99mtechnetium pertechnetate was conducted, and the patient was diagnosed with GD. Thiamazole treatment was then initiated, which led to improvement in symptoms. CONCLUSION: HLA typing revealed that both patients had the HLA-B*35:01, -C*04:01, and -DPB1*05:01 alleles. Only patient 2 had the HLA-DRB1*11:01 and HLA-DQB1*03:01 alleles. The HLA-B*35:01 and HLA-C*04:01 alleles appeared to be involved in the pathogenesis of SAT after SARS-CoV-2 vaccination, and the HLA-DRB1*11:01 and HLA-DQB1*03:01 alleles were speculated to be involved in the postvaccination pathogenesis of GD.

Emerging trends and hot spots in subacute thyroiditis research from 2001 to 2022: A bibliometric analysis.

Background: Subacute thyroiditis (SAT) is the most prevalent self-limiting thyroid disease that causes pain, accounting for about 5% of all clinical thyroid disorders. Numerous clinically noteworthy results have been published in this area over the last 20 years. However, no article has comprehensively assessed the relevant literature yet. We conducted a bibliometric analysis of SAT to provide light on the dynamic nature of scientific advancement and aid researchers in gaining a global perspective while examining research core themes and hotspots. Methods: SAT-related articles and reviews from 2001 to 2022 were retrieved from the Science Citation Index-Expanded of Web of Science Core Collection (WoSCC). We analyzed current research trends and hotspots in this area using CiteSpace and Vosviewer. Results: A total of 568 studies associated with SAT research were published in 282 academic journals by 2,473 authors in 900 institutions from 61 countries/regions. The United States was a crucial link in inter-country/region collaboration and was the most frequently involved country in international cooperation. The University of Missouri System was the top organization, and Braley-Mullen H. was the most productive researcher. Thyroid published the most papers, with 36 publications. The most co-cited article was "Clinical features and outcome of subacute thyroiditis in an incidence cohort: Olmsted County, Minnesota, study" (by Fatourechi V., 2003). The clustered network and timeline view of keywords showed that the prevalence, diagnosis, and treatment of SAT were the research core themes during the past 20 years. Analysis of keyword bursts indicated that the clinical characteristic and the influence of COVID-19 on SAT appeared to be the current research hotspots. Conclusion: This bibliometric analysis conducted a thorough review of the SAT research. The clinical characteristics and the genetic background of SAT under the influence of COVID-19 are current research hotspots. However, there is still a need for further study and global collaboration. Our findings can aid researchers in understanding the current status of SAT research and immediately pinpoint new directions for further investigation.

Subacute Thyroiditis Developing Within 2 Days of Vaccination Against COVID-19 with BNT162b2 mRNA.

A 32-year-old woman presented to the outpatient clinic with persistent fever, anterior neck pain, and palpitations over the past week which developed 2 days after she had received the first dose of the Pfizer/BioNTech SARS-CoV-2 mRNA vaccine. On examination, the patient's heart rate was 140 beats per minute and the thyroid gland was tender on palpation. Laboratory studies showed a low serum TSH level with elevated free thyroxine. Thyroid ultrasound revealed low-echoic lesions compatible with the site of tenderness. The patient was diagnosed with subacute thyroiditis and treatment was initiated with acetaminophen and propranolol, which resulted in symptom resolution within 2 weeks. Clinicians should be aware that subacute thyroiditis may occur within a few days following COVID-19 vaccination, especially in patients with anterior cervical pain with no significant abnormal pharyngeal findings and/or severe palpitations, because differentiating them from early non-specific adverse reactions can be challenging. LEARNING POINTS: Cases of subacute thyroiditis after vaccination, including against COVID-19, have been increasingly reported.Subacute thyroiditis should be considered in patients with anterior cervical pain with no significant abnormal pharyngeal findings and/or severe palpitations after COVID-19 vaccination because these can be diagnostic clues.It is important to note that this condition can occur as early as a few days after vaccination, in order to avoid diagnostic pitfalls.

COVID-19 and thyroid function: What do we know so far?

Coronavirus disease 2019 (COVID-19) was characterized as a pandemic in March, 2020 by the World Health Organization. COVID-19 is a respiratory syndrome that can progress to acute respiratory distress syndrome, multiorgan dysfunction, and eventually death. Despite being considered a respiratory disease, it is known that other organs and systems can be affected in COVID-19, including the thyroid gland. Thyroid gland, as well as hypothalamus and pituitary, which regulate the functioning of most endocrine glands, express angiotensin-converting enzyme 2 (ACE2), the main protein that functions as a receptor to which SARS-CoV-2 binds to enter host cells. In addition, thyroid gland is extremely sensitive to changes in body homeostasis and metabolism. Immune system cells are targets for thyroid hormones and T3 and T4 modulate specific immune responses, including cell-mediated immunity, natural killer cell activity, the antiviral action of interferon (IFN) and proliferation of T- and B-lymphocytes. However, studies show that patients with controlled hypothyroidism and hyperthyroidism do not have a higher prevalence of COVID-19, nor do they have a worse prognosis when infected with the virus. On the other hand, retrospective observational studies, prospective studies, and case reports published in the last two years reported abnormal thyroid function related to acute SARS-CoV-2 infection or even several weeks after its resolution. Indeed, a variety of thyroid disorders have been documented in COVID-19 patients, including non-thyroidal illness syndrome (NTIS), subacute thyroiditis and thyrotoxicosis. In addition, thyroid disease has already been reported as a consequence of the administration of vaccines against SARS-CoV-2. Overall, the data revealed that abnormal thyroid function may occur during and in the convalescence post-COVID condition phase. Although the cellular and molecular mechanisms are not completely understood, the evidence suggests that the "cytokine storm" is an important mediator in this context. Thus, future studies are needed to better investigate the pathophysiology of thyroid dysfunction induced by COVID-19 at both molecular and clinical levels.

COVID-19 vaccination and thyroiditis.

At the end of 2019, the world began to fight the coronavirus disease 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus-2. Many vaccines have quickly been developed to control the epidemic, and with the widespread use of vaccines globally, several vaccine-related adverse events have been reported. This review mainly focused on COVID-19 vaccination-associated thyroiditis and summarized the current evidence regarding vaccine-induced subacute thyroiditis, silent thyroiditis, Graves' disease, and Graves' orbitopathy. The main clinical characteristics of each specific disease were outlined, and possible pathophysiological mechanisms were discussed. Finally, areas lacking evidence were specified, and a research agenda was proposed.

Clinical, biochemical features and functional outcome of patients with SARS-CoV-2-related subacute thyroiditis: a review.

INTRODUCTION: SARS CoV-2 infection involves many organs and systems, including the thyroid, in which it manifests itself as subacute thyroiditis (SAT). After our first description of SAT due to SARS-CoV2 infection, other reports have confirmed the correlation between SARS-CoV-2 and SAT. We review the cases of SAT associated with COVID-19 to highlight its peculiar clinical and biochemical features, including its outcome and what it has added to our understanding of SAT. RESULTS: We have reviewed 24 articles, for a total of 69 cases of SAT related to SARS-CoV2 infection. All had neck pain, whereas thyrotoxicosis was documented in 68/68 who had their thyroid function checked. Ultrasound, performed in 67 patients, was typical of SAT in 65 and low uptake at scintigraphy was demonstrated in all 12 evaluated patients. Patients had a prompt response to the anti-inflammatory and/or glucocorticoid therapy, as expected in SAT. The rate of hypothyroidism was higher (36.5%) in COVID-19-related SAT compared to that observed in the pre-COVID era (10%). CONCLUSIONS: Clinical, biochemical, and instrumental features of SAT related to SARS-CoV2 are like those observed in SAT cases reported prior to COVID-19 pandemic, but it appears more severe.

Ultrasound-Guided Capsular Thyroid Injection Therapy With Dexamethasone and Lidocaine Mixture for Subacute Thyroiditis: A Single-Center Study.

OBJECTIVES: Subacute thyroiditis (SAT) is a self-limiting, inflammatory thyroid disease possibly caused by viral infection. In recent years, the incidence of SAT is increasing, especially during the pandemic of the COVID-19. This study aimed to evaluate the efficacy, safety, and recovery time of capsular thyroid injection therapy under ultrasound guidance for SAT. METHODS: A total of 73 patients with SAT were divided into two groups. Patients in group A (n = 48) received an ultrasound-guided capsular injection consisting of dexamethasone (DEX) and lidocaine in the thyroid lesion area, while patients in group B (n = 25) received oral prednisolone (PSL). The two groups were compared for pain relief and treatment duration, the recovery time of thyroid function, recurrence rates, hypothyroidism incidence, and drug-related side effects. RESULTS: The follow-up time was 1 year. In group A, the duration of pain relief, treatment, and recovery time of thyroid function were significantly shorter than that in group B (P < .05), and no statistically significant differences in recurrence rate or incidence of hypothyroidism were observed (P > .05). Weight gain was significantly higher in group A at the end of treatment (P < .001). CONCLUSIONS: Compared with oral PSL treatment, ultrasound-guided local injection of DEX and lidocaine into the capsular thyroid is a safe and effective procedure that can significantly reduce the treatment time of SAT.

Characteristics of Subacute Thyroiditis during COVID-19 Pandemic

Aim/Introduction: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is causing coronavirus disease (COVID-19), enters host cells via the angiotensin-converting enzyme 2 receptor. Its expression is higher in thyroid gland than in lungs. In the literature, an association between SARS-CoV-2 infection and subacute thyroiditis has been implicated. Therefore, we aimed to explore the influence of COVID-19 pandemic on the incidence and severity of subacute thyroiditis. Material(s) and Method(s): In our retrospective study we reviewed medical records of all patients who were referred for the first time to our thyroid department from 1 April 2019 to 31 May 2019 (before COVID-19) and from 1 April 2020 to 31 May 2020 (during COVID-19). Our institution has a stable catchment area of 1,000,000 inhabitants. Therefore, number of new cases may be considered the incidence of the disease. In each patient who was referred under suspicion of subacute thyroiditis, thyroid specialists performed clinical examination and thyroid ultrasound. In selected cases, thyroid scintigraphy was performed. Serum levels of free thyroxine (normal range 0.59-4.23 pmol/L) and free triiodothyronine (normal range 11.7-22.5 pmol/L) as well as sedimentation rate were measured. Result(s): In the two months period before COVID-19, we examined 946 patients (224 men/722 women) with the mean age 52.0>19.0 years, and in the two months period during COVID-19, we examined 576 patients (154 men/422 women) with the mean age 53.7>18.3 years. Between the two periods, patients did not differ with respect to sex and age (p=0.201 and p=0.438, respectively). Before COVID-19, we found 8 patients with subacute thyroiditis (0.8% from all in that period), while during COVID-19, we found 10 patients with COVID-19 (1.7% from all in that period). The incidence of subacute thyroiditis did not differ significantly between the two periods (p=0.189). Before COVID-19, patients with subacute thyroiditis had similar level of free thyroxine than during COVID-19 (median, range, 36.0 (7.2-70.4) pmol/L and 34.8 (14.7-70.4) pmol/L, respectively, p=0.929). Before COVID-19, the level of free triiodothyronine was similar than during COVID-19 (median, range, 10.9 (2.6-29.4) pmol/L and 9.5 (4.3-21.7) pmol/L, respectively, p=0.929). Before COVID-9, the sedimentation rate was similar than during COVID-19 (median, range, 65 (5-120) mm/h, and 57 (5-113) mm/h, respectively, p=0.916). Conclusion(s): Although we found absolutely and relatively more patients with subacute thyroiditis during COVID-19 than before, the results were not statistically significant. The same applies to the severity of the disease. A longer observation period would probably yield different results.