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.

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.

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.

Autoimmune and inflammatory thyroid diseases following vaccination with SARS-CoV-2 vaccines: from etiopathogenesis to clinical management.

Since the Covid-19 pandemic emerged in 2019, several adenoviral-vectored, mRNA-based and inactivated whole-virus vaccines have been developed. A massive vaccination campaign has been undertaken around the world, and an increasing number of SARS-CoV-2 vaccine-induced thyroid diseases have been described in the literature. Subacute thyroiditis has been reported in 52 patients, mean age 45.5 ± 1.8 years, mainly in women (n = 39). Graves' disease is more frequent in women (n = 22) than in men (n = 10), mean age 46.2 ± 2.6 years, reported as new onset, recurrent or exacerbation of well-controlled hyperthyroidism. The mean time to symptoms onset is 9.0 ± 0.8 days in subacute thyroiditis, and 15.1 ± 2.6 days in Graves' patients. Rare patients (n = 6) present silent or painless autoimmune thyroiditis. Thyroid function and autoimmune tests, inflammatory markers, thyroid echography with colour flow Doppler, radio-activity uptake on thyroid scan, medical treatment and follow-up are described and compared in patients with SARS-CoV-2 vaccine-induced thyroid diseases. The underlying pathogenic mechanisms of vaccine-induced thyroid diseases, molecular mimicry (various SARS-CoV-2 proteins sharing a genetic homology with a large heptapeptide human protein) or autoimmune/inflammatory syndrome induced by adjuvants (ASIA) are discussed in the context of predisposition or genetic susceptibility. The benefits of SARS-CoV-2 vaccination far outweigh the potential vaccine-induced adverse effects, but clinicians should be aware of possible autoimmune and inflammatory thyroid diseases, and can advise patients to seek medical assistance when experiencing anterior neck pain, fever or palpitations following SARS-CoV-2 vaccines. Further studies are warranted to investigate the etiopathogenesis and to clarify the factors which predispose patients to SARS-CoV-2 vaccine-induced thyroid diseases.

Subacute thyroiditis and COVID-19 vaccines: a case/non-case study.

PURPOSE: Some case reports have suggested a possible association between COVID-19 vaccines and subacute thyroiditis (SAT), however, to our knowledge, no study has analyzed this possible relationship. This study aimed to analyze whether a disproportionate number of cases of SAT were reported in the EudraVigilance database for four COVID-19 vaccines (BNT162b2, mRNA-1273 ChAdOx1-S or Ad26.COV2.S). METHODS: A case/non-case study was conducted to assess the association between SAT and COVID-19 vaccines, calculating the reporting odds ratios (RORs) up to December 2, 2021. Cases were selected using the preferred term 'subacute thyroiditis'. First, cases involving COVID-19 vaccines were compared with those involving all other drugs. Secondly, the RORs for COVID-19 vaccines compared with other viral vaccines (overall and influenza vaccines only) were obtained. RESULTS: Until December 2, 2021, of 1,221,582 spontaneous cases of adverse reactions with the four vaccines, we found 162 SAT cases: BNT162b2 (n = 103), mRNA-1273 (n = 27), ChAdOx1-S (n = 31) and Ad26.COV2.S (n = 1). SAT cases were found to be reported more frequently in association with BNT162b2, mRNA-1273, and ChAdOx1-S vaccines than with other drugs. Moreover, we found a signal of disproportionate reporting for SAT with BNT162b2 and mRNA-1273 vaccines comparing with other viral vaccines (BNT162b2 ROR 3.58, 95% CI 1.92-6.66; mRNA-1273 ROR 3.44, 95% CI 1.71-6.94). However, this association was absent when these COVID-19 vaccines were compared with influenza vaccines. CONCLUSIONS: In EudraVigilance, SAT is relatively more frequently reported in association with mRNA COVID-19 vaccines than with other viral vaccines. Well designed observational studies are needed to confirm these results.

Differences in Clinical Aspects Between Subacute Thyroiditis Associated with COVID-19 Vaccines and Classical Subacute Thyroiditis.

Subacute thyroiditis (SAT) developed after SARS-CoV-2 vaccines has been less studied. We aimed to compare classical SAT and SAT developed after SARS-CoV-2 vaccines in the context of clinical aspects. Adults with SAT detected in 90 days of COVID-19 vaccination (CoronaVac or Pfizer/BioNTech) were grouped as Vac-SAT. Those with a history of SARS-CoV-2 or upper respiratory tract infection in 6 months before the vaccination, or vaccination with another antiviral vaccine after COVID-19 vaccination were excluded. Those with SAT detected before COVID-19 pandemic were grouped as Classical-SAT. Of total (n=85), female/male (54/31) ratio and age [43 (23-65)] were similar in Vac-SAT (n=23) and Classical-SAT (n=62). Duration between vaccine and SAT was 45 (7-90) days, and similar in CoronaVac-SAT (n=5) and BioNTech-SAT (n=18). SAT-duration was 28 (10-150) days, and higher in Vac-SAT than in Classical-SAT (p=0.023). SAT was developed after the 1st dose vaccine in minority in CoronaVac-SAT (n=2) and BioNTech-SAT (n=3) (p=0.263). Previous LT4 use, and TSH elevation after resolution were more frequent in Vac-SAT than in Classical-SAT (p=0.027 and p=0.041). We included a considerable number of patients with SAT occurred after COVID-19 vaccines. We cannot provide clear evidence regarding the association of COVID-19 vaccines with SAT. SAT associated with CoronaVac or BioNTech seems unlikely to be occurred after the 1st dose, and to have a longer duration, more likely to be associated with previous LT4 use and lead TSH elevation after resolution than Classical-SAT. TSH should be followed-up after the resolution of SAT detected after COVID-19 vaccination.

Subacute Thyroiditis Following SARS-CoV-2 Vaccines: Six Cases Report and Review of the Literature.

Subacute thyroiditis (SAT) is an inflammatory disease of the thyroid that develops following viral upper respiratory tract infections. SARS-CoV-2 virus, the cause of COVID-19, binds to the Angiotensin-Converting Enzyme-2 (ACE2) molecule expressed on the target cell surface. Thyroid gland shows high levels of ACE2 expression. The cases of SARS-CoV-2-related subacute thyroiditis and Graves' disease have been reported. It has recently been noted that vaccines for SARS-CoV-2 also induce autoimmune and inflammatory reactions. We present six (4 male, 2 female) cases of SAT that developed after mRNA and inactivated SARS-CoV-2 vaccines. And we have reviewed the literature. SAT was seen in 5 patients after mRNA vaccine, in one after inactivated vaccine. Their clinic and laboratory findings suggested to SAT. They were treated with nonsteroid anti-inflamatory drugs and/or methylprednisolone.They recovered within few weeks. Out patients did not have permanent hypothyroidism after SAT. The history of SARS-CoV-2 vaccination should be questioned in patients with subacute thyroiditis in pandemic days.

Subacute Thyroiditis After Receiving the mRNA COVID-19 Vaccine (Moderna): The First Case Report and Literature Review in Korea.

Subacute thyroiditis (SAT) is a painful thyroiditis that often requires steroid therapy. Here, we report the first case of severe SAT in a patient who received the first dose of mRNA coronavirus disease 2019 (COVID-19) vaccination. A 34-year-old man without a viral prodrome felt a lump when swallowing 5 days after his first dose of mRNA-1273 (Moderna) vaccination. Ten days after vaccination, the patient visited the hospital and was advised to rest and take nonsteroidal anti-inflammatory drugs. He revisited the hospital 10 days later as symptoms aggravated with anterior neck pain, headache, fatigue, muscle weakness, and weight loss. Thyroid hormone levels and inflammatory markers were consistent with thyrotoxicosis. A thyroid ultrasound scan revealed typical SAT findings. His symptoms rapidly improved after receiving prednisone. A week later, the patient successfully completed his second dose of the vaccine. The thyroid function test results were nearly normal 1 month after the completion of the vaccination. We report this case to raise awareness of the occurrence of SAT after COVID-19 vaccination. As the risk of COVID-19 outweighs the minor risks of the vaccine, managing the side effects of the first vaccine dose is crucial to complete COVID-19 vaccination.

SARS-CoV-2 vaccine-associated subacute thyroiditis: insights from a systematic review.

PURPOSE: To perform a systematic review on published cases of subacute thyroiditis (SAT) secondary to SARS-CoV-2 vaccination, to highlight main features and increase the awareness of this condition. METHODS: Original reports of SAT developed after SARS-CoV-2 vaccination (mRNA, viral vector, or inactivated virus vaccines) were retrieved from a search of electronic databases. Individual patient data on demographics, medical history, type of vaccine, workup and therapies were collected. Wilcoxon rank-sum, Kruskal-Wallis and chi-squared tests were employed for comparisons. RESULTS: 30 articles including 48 reports were retrieved, 3 additional cases evaluated by the Authors were described and included for analysis. Of the 51 patients, 38 (74.5%) were women, median age was 39.5 years (IQR 34-47). Patients developed SAT after a median of 10 days (IQR 4-14) after the vaccine shot. Baseline thyroid exams revealed thyrotoxicosis in 88.2% of patients, decreasing at 31.6% at follow-up. Corticosteroids were used in 56.4% of treated patients. Patients undergoing non-mRNA vaccines were most frequently Asian (p = 0.019) and reported more frequently weight loss (p = 0.021). All patients with a previous diagnosis of thyroid disease belonged to the mRNA vaccine group. CONCLUSION: SARS-CoV-2 vaccine-associated SAT is a novel entity that should be acknowledged by physicians. Previous history of thyroid disease may predispose to develop SAT after mRNA vaccines, but further studies and larger cohorts are needed to verify this suggestion. SARS-CoV-2 vaccine-associated SAT is usually of mild/moderate severity and could be easily treated in most cases, thus it should not raise any concern regarding the need to be vaccinated.

Subacute thyroiditis during the COVID-19 pandemic: a prospective study.

PURPOSE: Subacute thyroiditis(SAT) is a destructive thyroiditis associated with viral infections. Several SAT cases associated with SARS-CoV-2 infection/vaccination were recently reported. We aimed to evaluate prospectively all cases applied to our tertiary center and their relationship with SARS-CoV-2 during 16 months of the pandemic. Cases during similar pre-pandemic period were recorded for numeric comparison. METHODS: Prospective study took place between March 2020 and July 2021. SAT was diagnosed by classical criteria. Swabs for SARS-CoV-2 and a wide respiratory viral panel (RV-PCR) were taken. Previous COVID-19 was assessed by SARS-CoV-2 IgM&IgG levels. Study group was divided into three as: CoV-SAT, patients who had or still have COVID-19, Vac-SAT, patients diagnosed within three months after SARS-CoV-2 vaccination and NonCoV-SAT, those not associated with COVID-19 or vaccination. RESULTS: Out of 64 patients, 18.8% (n = 12) was classified as CoV-SAT, 9.3% (n = 6) as Vac-SAT and 71.9% as (n = 46) NonCoV-SAT. SARS-CoV-2 RT-PCR tests on the diagnosis of SAT were negative in all, but two patients tested positive five days later, in second testing, performed upon clinical necessity. CoV-SAT and NonCoV-SAT groups were similar in terms of clinical, laboratory, and treatment characteristics. However, symptoms were milder and treatment was easier in Vac-SAT group (p = 0.006). CONCLUSIONS: Total number of SAT cases during the pandemic period was comparable to pre-pandemic period. However, a considerable rate of SARS-CoV-2 exposure in SAT patients was established. COVID-19 presented with SAT, as the first manifestation in three cases. Vaccine-related cases developed in a shorter time period, clinical presentation was milder, and only a few required corticosteroids.

Silent thyroiditis following vaccination against COVID-19: report of two cases.

PURPOSE: It is well established that thyroiditis and other thyroid disorders can be induced by COVID-19 infection, but there is limited information about the autoimmune/inflammatory syndrome induced by adjuvants (ASIA) after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination. We report two cases of thyrotoxicosis following SARS-CoV-2 vaccine. METHODS AND RESULTS: Two young health care peoples (wife and husband) received a first dose of SARS-CoV-2 vaccine, and few weeks later developed clinical manifestations of thyroid hyperactivity, with increased thyroid hormone levels on thyroid function tests, suppressed thyroid-stimulating hormone and negative antithyroid antibodies, despite being healthy before vaccination. They were diagnosed at the 4th week after first dose of SARS-Cov-2 vaccine as silent thyroiditis and followed without treatment, since their symptoms were not severe. At the 6th week, the patients became wholly asymptomatic and their thyroid function returned to normal. CONCLUSIONS: Thyrotoxicosis can occur after SARS-CoV-2 vaccination probably related to silent thyroiditis.

Two cases of subacute thyroiditis after different types of SARS-CoV-2 vaccination.

Although the development of subacute thyroiditis (SAT) following viral infections is well-documented, the actual mechanism has not been clearly elucidated. The occurrence of SAT after vaccination has been reported in several case series and possible mechanisms such as molecular mimicry due to the exposure to viral proteins and/or abnormal reactogenicity by adjuvants have been implicated. We describe two cases who developed SAT three days after the messenger RNA vaccine against COVID-19 (Pfizer-BioNTech®) and six days after the inactivated COVID-19 vaccine (CoronaVac®). SAT diagnosis of these patients was delayed for more than two weeks. When the current cases were evaluated together with 1 Pfizer-BioNTech® and 3 CoronaVac® related cases reported previously, the patients were female aged between 30-42, except for the male patient we presented, and the complaints of the patients initiated within the first 2-7 days. While two Pfizer-BioNTech® vaccine-related cases were severely symptomatic and thyrotoxic at presentation, there were cases with mild to moderate clinical manifestations in CoronaVac® vaccine-related group. Physicians should be aware of SAT that may occur within a few days following the COVID-19 vaccination.

Thyrotoxicosis following SARS-COV-2 vaccination: a case series and discussion.

AIM: To describe a case series of thyrotoxicosis likely triggered by SARS-CoV-2 vaccination and to warn physicians about this potential correlation. To report clinical, laboratory and imaging findings and provide further information that goes in line with the underlying mechanisms. METHODS: Single-center case series based on all the information collected in the hospital medical records, as well as the temporal sequence between the onset of symptoms and COVID-19 vaccination. RESULTS: We report 8 cases with thyrotoxicosis after SARS-CoV-2 vaccination. 4 cases of Graves' disease (GD), 2 cases of subacute painful thyroiditis (SAT), 1 case of concurrent GD and SAT and 1 case of atypical subacute thyroiditis. Five patients received BNT162b2 mRNA vaccine, 3 patients 1273 mRNA vaccine. The onset of symptoms following vaccination ranged from 10 to 14 days in six of eight patients and from 7 to 8 weeks in two patients. CONCLUSIONS: Several hypotheses have been proposed to explain the potential correlation between SARS-CoV-2 vaccination and thyrotoxicosis, including immune system hyper-stimulation, molecular mimicry and Autoimmune/Autoinflammatory Syndrome Induced by Adjuvants (ASIA). We should pay greater attention to thyroid disorders in patients receiving vaccine against SARS-CoV-2.

SARS-CoV-2 detection in primary thyroid sarcoma: coincidence or interaction?

INTRODUCTION: Thyroid dysfunctions associated with SARS-CoV-2 are emerging in scientific literature. During the second COVID-19 epidemic spread, we evaluated a patient with the suspect of subacute thyroiditis. METHODS AND RESULTS: Specimen from fine-needle aspiration of a hypoechoic undefined area was analyzed for cytology and for SARS-CoV-2 detection. SARS-CoV-2 was retrieved by real-time polymerase chain reaction on the cytologic sample, which was then cultured on Vero E6 cells and demonstrated to be cytopathic. Whole-genome sequence was deposited. Histological exam diagnosed a rare case of primary thyroid sarcoma with diffuse and strong expression of mouse double minute 2 homolog (MDM2) oncoprotein. Ultrastructural examination confirmed, in several neoplastic cells, the presence of viral particles in cytoplasmic vacuoles. CONCLUSIONS: In our hypothesis, SARS-CoV-2 and sarcoma coexistence could represent a synergistic interplay, ultimately favoring both viral persistence and tumor proliferation: the overexpression of MDM2 in tumor cells might have generated a favorable immunological niche for SARS-CoV-2 localization and, in turn, SARS-CoV-2 could have favored tumor growth by inducing MDM2-mediated p53 downregulation. Functional studies are needed to confirm this suggestive pathway.

Clinical Manifestation of Subacute Thyroiditis Triggered by SARS-CoV-2 Infection Can Be HLA-Dependent.

In the last two years, we have been struggling with the pandemic of SARS-CoV-2, the virus causing COVID-19. Several cases of subacute thyroiditis (SAT) have already been described as directly related to SARS-CoV-2 infection. The clinical course of SAT induced by SARS-CoV-2 can be entirely different from the classic SAT course, and one of the most important differences is a very rapid SAT onset observed in some patients, especially a phenomenon of the simultaneous presence of both diseases. The aim of this report is to compare HLA profile and clinical course of SAT in four patients, in whom SAT was considered as triggered by COVID-19, with special attention paid to the differences between a patient with rare simultaneous presence of SAT and COVID-19, and patients with longer time lag between the diseases. The unusual phenomenon of simultaneous occurrence of COVID-19 and SAT induced by SARS-CoV-2 infection can be HLA-dependent and related to the presence of homozygosity at HLA-B*35. Additionally, the clinical course of SAT triggered by COVID-19 can be HLA-related in regard to the risk of recurrence, and to a variety of other aspects, including severity of thyrotoxicosis.