The association of subacute thyroiditis with viral diseases: a comprehensive review of literature

Introduction: Subacute thyroiditis (SAT), also known as de Quatrain's thyroiditis or granulomatous thyroiditis, is an inflammatory disease of the thyroid. Most of the time, it manifests in the thirties to fifties and is more common in women. SAT can have either viral or post-viral origin. Some viruses, like influenza, COVID-19, Epstein-Barr virus, cytomegalovirus, hepatitis, coxsackievirus 16, and mumps virus, have been linked to SAT development. The COVID-19 pandemic has affected people's lives all around the world and has changed our attitude toward the treatment of many diseases. It has also made us look deeper into the subject in a way that we would be able to treat this sort of disease with a newer insight. Objective: Regarding the importance of this issue, we decided to summarize our extensive searches from online databases, including PubMed, Google Scholar, Medline, Web of Science, and Scopus until February 2023, which we found effective in elucidating the association of subacute thyroiditis and viral diseases. Method: Different online databases were searched for narrative review articles, systemic review articles, and original articles, which were published until February 2023. Result: According to the included studies, we found that there is a correlation between SAT and several viruses such as Epstein-Barr virus, influenza virus, human immunodeficiency virus, cytomegalovirus, oral and cervical virus, hepatitis, dengue virus, and SARS-COV-2. The effect of each of the viral diseases mentioned in the SAT is given in the text. Conclusions: According to the results mentioned in the text, because SAT may be challenging for early diagnosis, due to the potential of classic symptoms as well as the interference of similar clinical symptoms between thyrotoxicosis and viral reactions, the correlation between SAT and viral diseases should be considered so that we can avoid misdiagnosis and lateness.

Subacute thyroiditis following COVID-19 vaccination: Case presentation.

Background: Subacute thyroiditis (SAT) is an organ-specific disease that various drugs, including COVID-19 vaccines, can trigger. COVID-19 infection has been associated with thyroid gland damage and disease SARS-CoV-2 direct action, euthyroid sick syndrome, and immune-mediated mechanisms are all potential mechanisms of thyroid damage. It denotes thyroid gland inflammation, most commonly of viral origin, and belongs to the transitory, self-limiting thyroid gland diseases group, causing complications in approximately 15% of patients in the form of permanent hypothyroidism. Some authors say SAT is the most common thyroid disease associated with COVID-19.Purpose: The occurrence of SAT many weeks after administering the second COVID-19 vaccine is rare and has limited documentation in academic literature. This study aims to present the occurrence of SAT after administering the COVID-19 vaccine. We present the case of a 37-year-old man who developed SAT 23 days after receiving the second dose of Pfizer BioNTech's COVID-19 mRNA vaccine.Research design and study sample: Due to neck pain and an elevated body temperature (up to 38.2°C), a 37-year-old male subject presented for examination 23 days after receiving the second Pfizer BioNTech mRNA vaccine against SARS-CoV-2 viral infection. The patient denied ever having an autoimmune disease or any other disease. Painful neck palpation and a firm, slightly enlarged thyroid gland with no surrounding lymphadenopathy were identified during the exam. The heart rate was 104 beats per minute. All of the remaining physical findings were normal.Data collection and/or Analysis: Data collected during the disease are integral to the medical record.Results: Hematology and biochemistry analyses at the initial and follow-up visits revealed minor leukocytosis, normocytic anaemia, and thrombocytosis, followed by a mild increase in lactate dehydrogenase and decreased iron levels. The patient's thyroid function and morphology had recovered entirely from post-vaccine SAT.Conclusions: Results from this study emphasise the need for healthcare professionals to promptly report any case of SAT related to COVID-19 vaccination. Further investigation is warranted to understand the immunopathogenesis of COVID-19-associated thyroiditis and the impact of COVID-19 immunization on this condition.

Characteristics of patients with subacute thyroiditis.

INTRODUCTION: The diagnosis and management of subacute thyroiditis (SAT) may be challenging, and more evidence on patient and disease characteristics is warranted. METHODS: This was a retrospective cohort study of all patients in the North Denmark Region with a SAT diagnosis in the Danish National Patient Registry, 2016-2018. The medical records and biochemical results prior to the diagnosis and during a two-year follow-up period were reviewed. RESULTS: A total of 71 patients with a SAT diagnosis were identified, and the diagnosis was verified in 44 (62.0%) cases with an incidence rate of 2.4/100,000/year. Patients with verified SAT were predominantly females (72.7%) with a median age of 50.7 years. Biochemical results showed thyrotoxicosis at the initial examination in 69.8% and elevated C-reactive protein in 86.5% of patients. Longitudinal biochemical assessment showed a biphasic response (median thyroid-stimulating hormone, initially: 0.02 mIU/l, at three months: 4.7 mIU/l and 2.4 mIU/l after two years). Treatment with non-steroidal anti-inflammatory drugs, beta-blockers and/or prednisolone was initiated in 23 of the 38 patients (60.5%) evaluated, and ten of 33 patients (30.3%) with follow-up data received thyroid hormone replacement therapy. CONCLUSION: In the North Denmark Region, a hospital diagnosis of SAT was verified in less than two thirds of cases. Further large studies are warranted to extend the findings concerning the treatment and outcome of SAT. FUNDING: None. TRIAL REGISTRATION: Not relevant.

Beyond Acute COVID-19: Investigating the Incidence of Subacute Thyroiditis in Long COVID-19 in Korea.

BACKGRUOUND: The correlation between acute coronavirus disease 2019 (COVID-19) and subacute thyroiditis (SAT) has not been clearly investigated in "long COVID" patients. We aimed to investigate the incidence of SAT during convalescence and after the acute phase of COVID-19, comparing with that of the general population. METHODS: Data from a total of 422,779 COVID-19 patients and a control group of 2,113,895 individuals were analyzed. The index date was defined as the date 3 months after confirmation of COVID-19. The incidence rate (IR) of SAT and hazard ratios (HRs) were calculated per 100,000 persons. Subgroup analysis included analysis of HRs 90-179 and 180 days post-COVID-19 diagnosis; and additional analysis was conducted according to hospitalization status, sex, and age group. RESULTS: The IR of SAT was 17.28 per 100,000 persons (95% confidence interval [CI], 12.56 to 23.20) in the COVID-19 group and 8.63 (95% CI, 6.37 to 11.45) in the control group. The HR of COVID-19 patients was 1.76 (95% CI, 1.01 to 3.06; P=0.045). The HR of SAT was 1.39 (95% CI, 0.82 to 2.34; P=0.220) up to 6 months after the index date and 2.30 (95% CI, 1.60 to 3.30; P<0.001) beyond 6 months. The HR for SAT among COVID-19 patients was 2.00 (95% CI, 1.41 to 2.83) in hospitalized patients and 1.76 (95% CI, 1.01 to 3.06) in non-hospitalized patients compared to the control group. The IR of SAT was 27.09 (95% CI, 20.04 to 35.82) for females and 6.47 (95% CI, 3.34 to 11.30) for males. In the 19 to 64 age group, the IR of SAT was 18.19 (95% CI, 13.70 to 23.67), while the IR was 9.18 (95% CI, 7.72 to 10.84) in the 65 to 69 age group. CONCLUSION: SAT could be a potential long-term complication of COVID-19. Long-term surveillance for thyroid dysfunction is needed especially in hospitalized, female and young-aged subjects.

The value of FT4/TSH ratio in the differential diagnosis of Graves' disease and subacute thyroiditis.

Objective: To explore the value of the FT4/TSH ratio in the etiological diagnosis of newly diagnosed patients with thyrotoxicosis. Methods: The retrospective study was conducted on 287 patients with thyrotoxicosis (122 patients with subacute thyroiditis and 165 patients with Graves' disease) and 415 healthy people on their first visit to our hospital. All patients underwent thyroid function tests including the measurement of T3, T4, FT3, FT4, TSH, T3/TSH, and T4/TSH. The receiver operating characteristic (ROC) curve was employed to evaluate the value of FT4/TSH in the differential diagnosis of Graves' disease and subacute thyroiditis, and compared with other related indicators. Results: The area under the curve of FT4/TSH for diagnosing Graves' disease and thyroiditis was 0.846, which was significantly larger than the area under the curve of T3/T4 ratio (P< 0.05) and FT3/FT4 ratio (P< 0.05). When the cut-off value of the FT4/TSH ratio was 5731.286 pmol/mIU, the sensitivity was 71.52%, the specificity was 90.16%, the positive predictive value was 90.77% and the negative predictive value was 70.06%. The diagnostic accuracy was 79.44%. Conclusion: FT4/TSH ratio can be used as a new reference index for the differential diagnosis of thyrotoxicosis.

Subacute thyroiditis following recovery from COVID-19 infection: novel clinical findings from an Eastern Indian cohort.

OBJECTIVE: Recent reports have suggested a link between COVID-19 infection and subacute thyroiditis (SAT). We aimed to describe variations in clinical and biochemical parameters in patients developing post-COVID SAT. DESIGN: Ours was a combined retrospective-prospective study on patients presenting with SAT within 3 months of recovery from COVID-19 infection, who were subsequently followed up for a further 6 months since diagnosis of SAT. RESULTS: Out of 670 patients with COVID-19, 11 patients presented with post-COVID-19 SAT (6.8%). Those with painless SAT (PLSAT, n = 5) presented earlier, had more severe thyrotoxic manifestations and exhibited higher C-reactive protein, interleukin 6 (IL-6), neutrophil-lymphocyte ratio and lower absolute lymphocyte count than those with painful SAT (PFSAT, n = 6). There were significant correlations of total and free T4 and total and free T3 levels with serum IL-6 levels (pall <0.04). No differences were observed between patients with post-COVID SAT presenting during the first and second waves. Oral glucocorticoids were needed for symptomatic relief in 66.67% of patients with PFSAT. At 6 months of follow-up, majority (n = 9, 82%) achieved euthyroidism, while subclinical and overt hypothyroidism were found in one patient each. CONCLUSIONS: Ours is the largest single-centre cohort of post-COVID-19 SAT reported until, demonstrating two distinct clinical presentations-without and with neck pain-depending on time elapsed since COVID-19 diagnosis. Persistent lymphopaenia during the immediate post-COVID recovery period could be a key driver of early,painless SAT. Close monitoring of thyroid functions for at least 6 months is warranted in all cases.

Concurrent Subacute Thyroiditis and Graves' Disease After COVID-19: A Case Report.

There are many reports of subacute thyroiditis (SAT) that occurred after the coronavirus disease 2019 (COVID-19), but no such case has been reported in Korea. Moreover, the simultaneous occurrence of SAT and Graves' disease (GD) is rare. Here, we describe a patient who developed SAT and GD after the second episode of COVID-19. A 27-year-old woman with no known history of thyroid disease presented with fever, upper respiratory tract symptoms, and painful neck swelling. Thyroid function tests revealed thyrotoxicosis, and thyroid ultrasound showed heterogeneous echogenicity of enlarged thyroid glands. Her initial clinical presentation was consistent with SAT after viral infection, with typical neck tenderness and spontaneous improvement of thyrotoxicosis without antithyroid drug use. However, this case had some atypical features, such as an elevated thyroid-stimulating immunoglobulin level, relapse of thyrotoxicosis in short-term follow-up, and increased Tc-99m pertechnetate uptake, suggesting the coexistence of GD. About two months after methimazole (15 mg/day) was prescribed, she was lost to follow up again. We report the first case of unusual co-occurrence of SAT and GD following COVID-19.

A Rare Case of Painless Destructive Thyroiditis Resulting in Thyroid Storm.

Thyroid storm is a life-threatening clinical condition that is usually triggered by untreated or interrupted treatment of Graves' disease, leading to the sudden onset of severe thyrotoxicosis, which requires an immediate diagnosis and treatment based on diagnostic criteria. Cases of thyroid storm caused by painless/painless subacute thyroiditis are very rare. We herein report an 85-year-old man with features of severe thyrotoxicosis caused by painless/painless subacute thyroiditis who had no uptake of 99mTcO4 and was negative for thyroid-stimulating hormone receptor antibodies. In thyroid storm patients in whom the findings are inconsistent with Graves' disease, careful follow-up and management are necessary, assuming the possibility of painless or painless subacute thyroiditis.

Takotsubo cardiomyopathy with left ventricle thrombus caused by subacute thyroiditis.

We report a rare case of takotsubo cardiomyopathy caused by subacute thyroiditis in a man in his 50s. He went to the doctor with complaints of loss of appetite, diarrhoea, chills and general malaise. He had consciousness disturbance, thyrotoxicosis and thyroid-stimulating hormone (TSH) suppression. Thyroglobulin and C reactive protein levels in the blood were elevated, but TSH receptor antibody, thyroid-stimulating antibody, antithyroglobulin antibody and antithyroid peroxidase antibody were not. We began treatment with prednisolone and propranolol after he was diagnosed with thyroid storm caused by subacute thyroiditis. The ECG revealed inverted T waves on the fifth day after admission. He was newly diagnosed with takotsubo cardiomyopathy on the day. A large thrombus was detected in the left ventricle, requiring anticoagulation therapy. Thus, even if there are no findings of takotsubo cardiomyopathy or thrombus at the onset of thyroid storm, appropriate monitoring is required because they can develop during the treatment course.

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.

Subacute thyroiditis presenting as simple acute headache was misdiagnosed as meningitis: case report and literature review.

BACKGROUND: The relationship between headache and thyrotoxicosis has been occasionally mentioned in case reports, but there are few related reports. Thus, the relationship cannot be determined. Few cases of subacute thyroiditis (SAT) presenting as simple headache have been reported. CASE PRESENTATION: This case report describes a middle-aged male patient who came to our hospital with acute headache for 10 days. He was initially misdiagnosed as meningitis due to headache, fever, and increased C-reactive protein. Routine antibacterial and antiviral therapy did not improve his symptoms. Blood test suggested thyrotoxicosis, and color ultrasound suggested SAT sonography. He was diagnosed with SAT. With the treatment of SAT, the headache was relieved after the thyrotoxicosis improved. CONCLUSION: This patient is the first detailed report of SAT presenting with simple headache, which is helpful for clinicians to differentiate and diagnose atypical SAT.

A Case of Thyroid Storm Caused by Thyroiditis.

Thyroid storm occurs when thyroid hormones are released causing a hyperadrenergic state resulting in potentially life-threatening cardio-respiratory effects. The most common cause of thyroid storm is thyrotoxicosis secondary to Graves disease. Alternatively, subacute thyroiditis (SAT) is usually a self-limited condition consisting of painful inflammation of thyroid gland, often associated with viral illness. Transient hyperthyroidism is a common finding in SAT; however, thyroid storm is an extremely rare complication of SAT. We report the sixth recorded case of SAT associated with thyroid storm.

Subacute Thyroiditis after COVID-19: A Literature Review.

Subacute thyroiditis (SAT), potentially caused by severe acute respiratory syndrome coronavirus 2 infection, has been reported as a complication of COVID-19 since 2020. The clinical characteristics and outcomes of SAT after COVID-19 remain incompletely defined. Therefore, we aimed to collect and survey case reports of SAT after COVID-19. We performed a systematic search of PubMed/MEDLINE, Web of Science, and Google Scholar. The keywords and MeSH terms used for the searches were "subacute thyroiditis" and "COVID-19." A total of 38 patients from 26 case reports, case series, and letters on SAT associated with COVID-19 were included and analyzed. The most frequent SAT symptom was neck pain (27 cases), followed by fever (22 cases). Of the 25 cases with information on the duration between onset of COVID-19 symptoms and onset of SAT symptoms, the shortest was simultaneous occurrence, and the longest was 4 months. In most cases, patients developed SAT at several days or weeks after the onset of COVID-19. All patients with SAT recovered with no severe complications or sequelae. Clinicians should be aware of the possibility of SAT development in patients with neck pain and fever following COVID-19. Further research is necessary to determine the relationship between SAT and COVID-19.

Incidence of Subacute Thyroiditis During the COVID-19 Pandemic in South Korea Using the National Health Insurance Service Database.

Background: Subacute thyroiditis (SAT) is a thyroid disease initiated by viral infection. Whether severe acute respiratory syndrome coronavirus 2 infection can cause SAT is unclear. This study investigated changes in the nationwide incidence of SAT during the coronavirus disease 2019 (COVID-19) pandemic. Methods: This is a retrospective, cross-sectional population-based study. Data regarding SAT and related viral diseases, including COVID-19, from 2017 to 2020 were collected from the National Health Insurance Service and Korea Disease Control and Prevention Agency databases. Results: In a total of 15,447 patients, 2484 men and 12,963 women diagnosed with SAT from 2017 to 2020 were included in this study. The incidence of SAT was significantly higher in 2020 than in 2017-2019 (8.30 vs. 7.27 per 100,000 persons, p < 0.001), while the incidence of SAT-related respiratory viral diseases, except for COVID-19, markedly decreased in 2020. The peak age of SAT incidence in 2020 was 50-59 years, and the women-to-men ratio was 5.4 (similar to that in 2017-2019). Corticosteroids were prescribed more often (72% vs. 58%, p < 0.001), and the prescription rate exceeding 1 month was significantly higher (45% vs. 40%, p < 0.01) in 2020 than in 2017-2019. Conclusions: The incidence of SAT increased in 2020 in association with COVID-19. A diagnostic approach to COVID-19 needs to be considered in patients with SAT during the COVID-19 pandemic.

Subacute Thyroiditis-Still a Diagnostic Challenge: Data from an Observational Study.

Background: Subacute thyroiditis (SAT) is a relatively common cause of thyroid disease. However, only a few studies evaluating SAT have been published in recent years with varying diagnostic criteria. We evaluate the clinical presentation and long-term outcome of isotope scan-confirmed SAT. Methods: A retrospective study of 38 patients with isotope scan-confirmed SAT was performed at a single isotope department. All patients were contacted for long-term follow-up. Results: The female/male ratio was 1.4:1, and mean age was 47 ± 14 years and 62 ± 12 years in women and men, respectively (p = 0.002). Almost half of the cases (42%) occurred during the summer. The most common symptoms were neck pain (74%) and weakness (61%). Palpitations, weight loss, heat intolerance, and sweating appeared in 50%, 42%, 21%, and 21%, respectively. Only half of the patients reported fever. TSH level was low in all patients, and mean FT4 and FT3 level were about twice the upper limit of normal range. Elevated CRP and ESR occurred in the majority (88%) of patients. The mean time period between the first clinic visit and performing thyroid function tests was 8 ± 7 days. One-third of the patients initially received a diagnosis of upper respiratory tract infection (URI). NSAIDs and steroids were prescribed to 47% and 8% of patients, respectively. Long-term follow-up of 33.5 months (range 9-52) revealed that 25% remained with subclinical or overt hypothyroidism. Conclusions: These data demonstrate that although SAT is a common entity, there is still a significant delay in diagnosis, and in a third of our patients, the initial diagnosis was URI, with 25% developing long-term hypothyroidism.

Lessons of the month 1: A diagnostic dilemma: thyroid abscess or subacute thyroiditis?

Thyroid abscess is rare but potentially fatal, whereas subclinical thyroiditis is a self-limiting condition that is more commonly seen. The clinical features of both diseases can be overlapping but the treatment approach differs. We report a case of a painful left thyroid nodule not responding to conventional therapy for thyroiditis or thyroid abscess.

Subacute thyroiditis after SARS-Cov2 vaccination: A review of the cases being described and personal experience.

Objective. The present study evaluates the occurrence of subacute thyroiditis in temporal connection with SARS-Cov2 vaccinations described in the literature last year and confirmed by our clinical routine. Methods. Systematic literature search in Medline for studies reporting diagnosis of subacute thyroiditis in temporal connection with vaccinations against Covid 19. Results. The literature search yielded 24 relevant references out of which 22 were "case reports" and two "Letters to the Editor" and encompassed 37 patient cases, in total. They had received a SARS-Cov2 vaccination shortly before the diagnosis (median interval to vaccination six days). In none of these cases, infection of the upper respiratory tract had previously been identified as a classic trigger of the disease. Newly occurring hyperthyroidism and increased laboratory signs of inflammation were described in 78% and 74% of cases, respectively. Atypical clinical pictures (asymptomatic, euthyroid, no inflammation marks) have been observed in both the literature and our patients suspected of thyroid cancer referred to surgery. Conclusions. In times of pandemics and the resulting vaccination, new rapidly occurring sonographic changes in the thyroid gland should be revaluated after 2-3 weeks, or recommended to undergo a fine-needle biopsy, in order to avoid unnecessary surgical interventions.

Can the systemic immune-inflammation index be used as a novel diagnostic tool in the diagnosis of subacute thyroiditis?

Aim: To evaluate systemic inflammatory parameters derived from hematological parameters in the diagnosis and prognosis of subacute thyroiditis (SAT). Methods: Demographic and laboratory data of 170 patients with SAT and 91 healthy control subjects were analysed retrospectively. The authors compared inflammatory parameters and thyroid function tests between SAT and control groups. Results: The erythrocyte sedimentation rate, neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio and systemic immune-inflammatory index (SII) were significantly higher in patients with SAT (p < 0.001). There was a significant positive correlation between the SII and erythrocyte sedimentation rate (r: 0.448; p < 0.001), CRP (r: 0.449; p < 0.01), neutrophil-to-lymphocyte ratio (r: 0.861; p < 0.001) and platelet-to-lymphocyte ratio (r: 0.782, p < 0.001). The thyroid stimulating hormone levels were higher in patients with recurrence when compared with those without recurrence (p = 0.007). Conclusions: As a practical biomarker, SII was significantly higher in patients with SAT compared with the control group. SII may be a new diagnostic tool for SAT.

Evaluation of the diagnostic features and clinical course of COVID-19 vaccine-associated subacute thyroiditis.

OBJECTIVE: This study aimed to identify cases of coronavirus disease 2019 (COVID-19) vaccine-associated subacute thyroiditis (SAT) during the active vaccination period of the pandemic, analyze the characteristics of these cases, and compare them with cases of non-vaccine associated SAT diagnosed in the same period. METHODS: A total of 55 patients diagnosed with SAT in our outpatient clinic between February and October, 2021, were included in this retrospective single-center study. RESULTS: Of the study population, 16 (29.1%) were diagnosed with COVID-19 vaccine-associated SAT (10 with CoronaVac® and six with Pfizer-BioNTech® vaccine), with a median time to onset of symptoms after vaccination of 6.5 (range, 2-20) days. There was no statistically significant difference between the vaccine-associated (VA) and non-vaccine associated (NVA) groups in terms of age, gender, time to diagnosis, thyroid volumes, thyroid function tests, and acute phase reactants. Seven (43.8%) and 25 (64.1%) patients were treated with methylprednisolone in the VA group and NVA group, respectively (p = 0.16). Follow-up data of 45 patients (16/16 for VA and 29/39 for NVA) were available. The mean follow-up of these patients was 47.4 ± 19.4 days, and the follow-up periods of the VA group and NVA group were comparable (p = 0.24). There was no difference between the two groups in terms of the frequency of euthyroidism at the follow-up visit (12/16 vs.14/29, p = 0.08). CONCLUSION: With the increase in COVID-19 vaccination rates during the current pandemic, VA SAT cases are seen more frequently. The present study demonstrated that these cases have similar diagnostic features and clinical course to that of classic forms of SAT. In addition, most patients with VA SAT had a mild clinical course that improved with non-steroidal anti-inflammatory drugs.