Subacute thyroiditis post-Pfizer-BioNTech mRNA vaccination for COVID-19

SARS-CoV-2-Vaccine-Related Endocrine Disorders: An Updated Narrative Review

The emergence of the COVID-19 pandemic has led to the rapid and worldwide development and investigation of multiple vaccines. While most side effects of these vaccines are mild and transient, potentially severe adverse events may occur and involve the endocrine system. This narrative review aimed to explore the current knowledge on potential adverse endocrine effects following COVID-19 vaccination, with thyroid disorders being the most common. Data about pituitary, adrenal, diabetes, and gonadal events are also reviewed. This review also provides a comprehensive understanding of the pathogenesis of endocrine disorders associated with SARS-CoV-2 vaccines. PubMed/MEDLINE, Embase database (Elsevier), and Google Scholar searches were performed. Case reports, case series, original studies, and reviews written in English and published online up to 31 August 2023 were selected and reviewed. Data on endocrine adverse events of SARS-CoV-2 vaccines are accumulating. However, their causal relationship with COVID-19 vaccines is not strong enough to make a definite conclusion, and further studies are needed to clarify the pathogenesis mechanisms of the endocrine disorders linked to COVID-19 vaccines.

Autoimmune/inflammatory syndrome induced by adjuvants (ASIA): past, present, and future implications

Adjuvants, as the name indicates, are adjoined material aimed to assist in functioning as when added to vaccines they are meant to boost the effect and strongly stimulate the immune system. The response of the immune system can be unpredictable, and the autoimmune/inflammatory syndrome induced by adjuvants (ASIA) was developed to address possible adverse reactions of an autoimmune and inflammatory type that may be caused by adjuvants. While ASIA, as a syndrome, was coined and defined in 2011; reports describing patients with vague and nonspecific clinical symptoms following vaccinations appeared much earlier. In other words, ASIA came to define, arrange, and unite the variety of symptoms, related to autoimmunity, caused not by the vaccine itself, rather by the adjuvant part of the vaccine such as aluminum, among others. Accordingly, the introduction of ASIA enabled better understanding, proper diagnosis, and early treatment of the disorder. Furthermore, ASIA was shown to be associated with almost all body systems and various rheumatic and autoimmune diseases such as systemic lupus erythematosus, antiphospholipid syndrome, and systemic sclerosis. In addition, the correlation between COVID-19 and ASIA was noticed during the pandemic. In this review, we summarized the reported effects of adjuvants and medical literature before and after ASIA was defined, the several ways ASIA can manifest and impact different systems of the body, and the incidences of ASIA during the COVID-19 pandemic. It is important to clarify, that vaccines are among, if not the, most effective means of fighting infectious diseases however, we believe that vaccines manufacturing is not above criticism, particularly when it comes to added substances possessing a risk of side effects.

Insights into SARS-CoV-2-associated subacute thyroiditis: from infection to vaccine

Since the COVID-19 emergence as a global pandemic in March 2020, more than 5 million SARS-CoV-2-related deaths have been globally documented. As the pandemic progressed, it became clear that, although the infection is mainly characterized as a respiratory disease, it also affects other organs and systems, including the thyroid gland. Indeed, emerging evidence suggests that SARS-CoV-2 can act as a trigger for various thyroid disorders, for example, subacute thyroiditis (SAT), Grave's disease, and non-thyroidal illness syndrome. The entry of SARS-CoV-2 into the host cells is mainly mediated by the ACE2-receptor, making organs and systems with high expression of this receptor, such as the thyroid gland, highly vulnerable to COVID-19. Accumulating data propose that SAT may be an underestimated manifestation of COVID-19 infection. Importantly, if SAT remains unrecognized, it may trigger or aggravate potential other complications of the disease, for example, respiratory insufficiency and cardiovascular complications, and thus negatively influence prognosis. Moreover, recent case reports, case series, and systematic reviews highlight SAT as a potential side effect of the vaccination against SARS-CoV-2. The present review aims to raise awareness of SARS-CoV-2-associated- and post-vaccination subacute thyroiditis, to discuss recent evidence regarding its pathophysiology, and to present useful information for this special form of SAT related to daily clinical practice.

Overt Hypothyroidism Status Post Pfizer-BioNTech Vaccination: A Case Study

Coronavirus disease (COVID-19) is among the most contagious viral illnesses, affecting millions worldwide. Although precautions such as social distancing, hand sanitizing, and the use of masks decreased the transmission of the virus, the situation went uncontrolled until vaccination came to light. Vaccination was vital in limiting the incidence, prevalence, and severity caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Based on the mechanism, several types of vaccines, such as Pfizer-BioNTech, Moderna, AstraZeneca, Johnson & Johnson, and Covaxin, were approved by the US Food and Drug Administration (FDA). A booster dose was implemented as the vaccine's effectiveness decreased with time. Several side effects, such as fever, soreness around the injection site, fatigue, chills, muscle weakness, and headache, have been reported after vaccination with Pfizer-BioNTech, but thyroid dysfunction is relatively rare. Several case reports and even case series describing links between COVID-19 vaccination and various types of thyroid dysfunction have appeared in the literature. However, the exact reasons have yet to be explained. This report presents the case of a healthy 50-year-old woman diagnosed with overt hypothyroidism three weeks after the administration of the Pfizer-BioNTech vaccine.

Evaluation of metabolic changes in FDG PET/CT imaging after mRNA-based COVID-19 vaccination

BACKGROUND

It isimportant to evaluate the vaccine-related metabolic changes on FDG PET/CT to avoid confusing results. We here aimed to assess the frequency and intensity of regional and systemic metabolic PET/CT changes of patients who received the mRNAbased COVID-19 vaccine (BNT162b2-Pfizer/BioNTech) and to analyze possible factors affecting these changes.

METHODS

Among the patients who underwent FDG PET/CT for any indication in our department between July 2021 and December 2021, 129 volunteer patients with a history of COVID-19 vaccination were included in this prospective observational study. Bilateral axillary lymph nodes, ipsilateral deltoid muscle, bone marrow, spleen, thyroid, and liver FDG uptakes were evaluated visually and semiquantitatively for each examination.

RESULTS

The frequencies of positive axillary lymph nodes after vaccination were 40%, 44.4%, 32.6%, and 44.7% in all, 1st dose, 2nd dose, and heterologous vaccination regimens groups, respectively. Maximum standardized uptake values of spleen, liver, and bone marrow were statistically high in patients with positive axillary lymph nodes than with negative ones (p < 0.05). Positive deltoid muscle uptake and diffusely increased thyroid uptake findings were observed in 10 and 8 patients, respectively. The median time interval between vaccination and imaging was 9.5 days for patients with positive axillary lymph nodes and 17 days for patients with negative nodes. In our study group, only 8 patients had a positive documented history of COVID-19 infection.

DISCUSSION

Regional and systemic metabolic changes were occasionally found on FDG PET/CT imaging in patients who received the mRNA-based COVID-19 vaccine. To avoid these timely decreasing changes, we recommend managing the ideal timing of imaging or vaccination and taking a careful history.

Thyroid dysfunction following vaccination with COVID-19 vaccines: a basic review of the preliminary evidence

PURPOSE

The safety and efficacy of the several types of COVID-19 vaccines, including mRNA-based, viral vector-based, and inactivated vaccines, have been approved by WHO. The vaccines can confer protection against severe SARS-CoV-2 infection through induction of the anti-spike protein neutralizing antibodies. However, SARS-CoV-2 vaccines have been associated with very rare complications, such as thyroid disorders. This review was conducted to highlight main features of thyroid abnormalities following COVID-19 vaccination.

METHODS

A comprehensive search within electronic databases was performed to collect reports of thyroid disorders after vaccination with COVID-19 vaccines.

RESULTS

Among 83 reported cases including in this review, the most cases of thyroid abnormalities were observed after vaccination with mRNA-based vaccines (68.7%), followed by viral vector vaccines (15.7%) and 14.5% cases following inactivated vaccines. Subacute thyroiditis (SAT) was the most common COVID-19 vaccination-related thyroid disease, accounting for 60.2% of all cases, followed by Graves' disease (GD) with 25.3%. Moreover, some cases with focal painful thyroiditis (3.6%), silent thyroiditis (3.6%), concurrent GD and SAT (2.4%), thyroid eye disease (1.2%), overt hypothyroidism (1.2%), atypical subacute thyroiditis (1.2%), and painless thyroiditis with TPP (1.2%) were also reported. Overall, in 58.0% of SAT cases and in 61.9% of GD cases, the onset of the symptoms occurred following the first vaccine dose with a median of 10.0 days (ranged: 3-21 days) and 10.0 days (ranged: 1-60 days) after vaccination, respectively. Moreover, 40.0% of SAT patients and 38.1% of GD patients developed the symptoms after the second dose with a median of 10.5 days (ranged: 0.5-37 days) and 14.0 days (ranged: 2-35 days) after vaccination, respectively.

CONCLUSION

Fortunately, almost all cases with COVID-19 vaccination-associated thyroid dysfunctions had a favorable outcome following therapy. The benefits of COVID-19 vaccinations in terms of terminating the pandemic and/or reducing mortality rates can exceed any risk of infrequent complications such as a transient thyroid malfunction.

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.

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.

SARS-CoV-2 mRNA Vaccination and Graves' Disease: A Report of 12 Cases and Review of the Literature

CONTEXT AND OBJECTIVE

Thyroid autoimmunity has been reported to be associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the SARS-CoV-2 vaccination recently. We report a series of patients who presented with new onset or relapse of Graves' disease-related hyperthyroidism shortly after receiving the SARS-CoV-2 messenger RNA (mRNA) vaccine at a single tertiary institution in Singapore.

METHODS AND RESULTS

We describe 12 patients who developed hyperthyroidism within a relatively short interval (median onset, 17 [range, 5-63] days) after receiving the SARS-CoV-2 mRNA vaccine. The majority were females (11/12) with median age of 35.5 (range, 22-74) years. Six patients had new-onset hyperthyroidism, whereas the other 6 had relapse of previously well-controlled Graves' disease. TSH receptor antibody concentrations ranged from 2.4 to 32 IU/L. The majority of the patients were able to go for the second dose of the vaccine without any further exacerbations. Literature review revealed 21 other similar cases reported from across the world.

CONCLUSION

Our case series provides insight into the characteristics of individuals in whom Graves' disease was triggered by the SARS-CoV-2 vaccination. Clinicians need to be vigilant of precipitation or exacerbation of autoimmune thyroid disorders in predisposed individuals after exposure to the SARS-CoV-2 vaccination. Further epidemiological and mechanistic studies are required to elucidate the possible associations between the SARS-CoV-2 vaccines and the development of thyroid autoimmunity.

Autoimmune post-COVID vaccine syndromes: does the spectrum of autoimmune/inflammatory syndrome expand?

To date, around 60% of the world population has been protected by vaccines against SARS-CoV-2, significantly reducing the devastating effect of the pandemic and restoring social economic activity through mass vaccination. Multiple studies have demonstrated the effectiveness and safety of vaccines against COVID-19 in healthy populations, in people with risk factors, in people with or without SARS-CoV-2 infection, and in immunocompromised people. According to the criteria for post-vaccine adverse events established by the World Health Organization, a minority of individuals may develop adverse events, including autoimmune syndromes. The exact mechanisms for the development of these autoimmune syndromes are under study, and to date, a cause-effect relationship has not been established. Many of these autoimmune syndromes meet sufficient criteria for the diagnosis of Adjuvant-Induced Autoimmune Syndrome (ASIA syndrome). The descriptions of these autoimmune syndromes open new perspectives to the knowledge of the complex relationship between the host, its immune system, with the new vaccines and the development of new-onset autoimmune syndromes. Fortunately, most of these autoimmune syndromes are easily controlled with steroids and other immunomodulatory medications and are short-lived. Rheumatologists must be alert to the development of these autoimmune syndromes, and investigate the relationship between autoimmune/inflammatory symptoms and vaccination time, and assess their therapeutic response.

Two Case Reports of Subacute Thyroiditis after Receiving Vaccine for COVID-19

The ongoing COVID-19 pandemic, caused by a coronavirus named SARS-CoV-2, has struck the planet with great force. As of December 2019, the virus has made its devasting route across all continents . In January 2022, the World Health Organization (WHO) registered over 5.5 million COVID-19 related deaths. Most of these people had suffered from pneumonia and acute respiratory distress syndrome , and in some cases, extensive damage to all organ systems. To get hold of this pandemic, it was vital to find effective vaccines against it. The two vaccine candidates BNT162b2 (BioNTech/Pfizer) and ChAdOx1 (University of Oxford and AstraZeneca) offer a high level of protection against COVID-19 by providing immunity due to antibody production against the spike protein of SARS-CoV-2. In addition to general side effects, immunological side effects such as subacute thyroiditis can follow the vaccination. This transient inflammatory condition of the thyroid gland is characterized with hyperthyroxinemia, inflammation, pain, and tenderness in the thyroid region, as well as an elevation of serum thyroglobulin concentration. There are only a few reports on the occurrence of this disease after receiving a COVID-19 vaccine. We present two cases of subacute thyroiditis after vaccination with the vaccines BNT162b2 and ChAdOx1 and try to enlighten the problem of immunological phenomena after vaccination. It must be discussed whether cross-reactivity of the spike protein and tissue proteins such as thyroid peroxidase (TPO), an “autoimmune/inflammatory syndrome by adjuvants” (ASIA), or the circulating spike protein itself after vaccination are responsible for the SAT.

The New Entity of Subacute Thyroiditis amid the COVID-19 Pandemic: From Infection to Vaccine

This is a review of full-length articles strictly concerning subacute thyroiditis (SAT) in relation to the SARS-CoV-2 virus infection (SVI) and COVID-19 vaccine (COV) that were published between the 1st of March 2020 and the 21st of March 2022 in PubMed-indexed journals. A total of 161 cases were reported as follows: 81 cases of SAT–SVI (2 retrospective studies, 5 case series, and 29 case reports), 80 respective cases of SAT–COV (1 longitudinal study, 14 case series, 17 case reports; also, 1 prospective study included 12 patients, with 6 patients in each category). To our knowledge, this represents the largest cohort of reported cases until the present time. SAT–SVI was detected in adults aged between 18 and 85 years, mostly in middle-aged females. SAT–COVID-19 timing classifies SAT as viral (synchronous with infection, which is an original feature of SATs that usually follow a viral infection) and post-viral (during the recovery period or after infection, usually within 6 to 8 weeks, up to a maximum 24 weeks). The clinical spectrum has two patterns: either that accompanying a severe COVID-19 infection with multi-organ spreading (most frequent with lung involvement) or as an asymptomatic infection, with SAT being the single manifestation or the first presentation. Either way, SAT may remain unrecognized. Some data suggest that more intense neck pain, more frequent fever, and more frequent hypothyroidism at 3 months are identified when compared with non-SAT–SVI, but other authors have identified similar presentations and outcomes. Post-COVID-19 fatigue may be due to residual post-SAT hypothyroidism. The practical importance of SAT–SVI derives from the fact that thyroid hormone anomalies aggravate the general status of severe infections (particular concerns being tachycardia/arrhythmias, cardiac insufficiency, and ischemic events). If misdiagnosed, SAT results in unnecessary treatment with anti-thyroid drugs or even antibiotics for fever of unknown cause. Once recognized, SAT does not seem to require a particular approach when compared with non-COVID-19 cases, including the need for glucocorticoid therapy and the rate of permanent hypothyroidism. A complete resolution of thyroid hormone anomalies and inflammation is expected, except for cases with persistent hypothyroidism. SAT–COV follows within a few hours to a few weeks, with an average of 2 weeks (no particular pattern is related to the first or second vaccine dose). Pathogenesis includes molecular mimicry and immunoinflammatory anomalies, and some have suggested that this is part of ASIA syndrome (autoimmune/inflammatory syndrome induced by adjuvants). An alternative hypothesis to vaccine-related increased autoimmunity is vaccine-induced hyperviscosity; however, this is supported by incomplete evidence. From what we know so far concerning the risk factors, a prior episode of non-SVI–SAT is not associated with a higher risk of SAT–COV, nor is a previous history of coronavirus infection by itself. Post-vaccine SAT usually has a less severe presentation and a good outcome. Generally, the female sex is prone to developing any type of SAT. HLA susceptibility is probably related to both new types of SATs. The current low level of statistical evidence is expected to change in the future. Practitioners should be aware of SAT–COV, which does not restrict immunization protocols in any case.

Autoimmune post-COVID vaccine syndromes: does the spectrum of autoimmune/inflammatory syndrome expand?

To date, around 60% of the world population has been protected by vaccines against SARS-CoV-2, significantly reducing the devastating effect of the pandemic and restoring social economic activity through mass vaccination. Multiple studies have demonstrated the effectiveness and safety of vaccines against COVID-19 in healthy populations, in people with risk factors, in people with or without SARS-CoV-2 infection, and in immunocompromised people. According to the criteria for post-vaccine adverse events established by the World Health Organization, a minority of individuals may develop adverse events, including autoimmune syndromes. The exact mechanisms for the development of these autoimmune syndromes are under study, and to date, a cause-effect relationship has not been established. Many of these autoimmune syndromes meet sufficient criteria for the diagnosis of Adjuvant-Induced Autoimmune Syndrome (ASIA syndrome). The descriptions of these autoimmune syndromes open new perspectives to the knowledge of the complex relationship between the host, its immune system, with the new vaccines and the development of new-onset autoimmune syndromes. Fortunately, most of these autoimmune syndromes are easily controlled with steroids and other immunomodulatory medications and are short-lived. Rheumatologists must be alert to the development of these autoimmune syndromes, and investigate the relationship between autoimmune/inflammatory symptoms and vaccination time, and assess their therapeutic response.

Thyroid Inconveniences With Vaccination Against SARS-CoV-2: The Size of the Matter. A Systematic Review

After the beginning of COVID-19 vaccination campaigns, several reports of thyroid disease possibly related to the COVID-19 vaccination progressively appeared in the literature, raising the question of whether the thyroid disorder might be a SARS-CoV-2 vaccine complication. The aim of this study was to analyze the data about COVID-19 vaccination and thyroid disease, evaluate the size and quality of related literature, assess the type of these events, and investigate their timing of onset with respect the vaccination. Pubmed/MEDLINE and Cochrane were systematically reviewed until February 2022 to retrieve the largest number of original papers, case reports, and case series articles reporting thyroid disease after SARS-CoV-2 vaccination. Forty-six articles were included with a total of 99 patients aged from 26 to 73 years were described, of whom 74.75% female. Regarding the vaccination received, 49.49% of patients received Comirnaty (Pfizer/BioNTech), 14.14% CoronaVac (Sinovac), 12.12% Vaxzevria (Oxford/Astrazeneca), 11.11% Spikevax (Moderna), 3.03% Ad26.COV2.S (Janssen, Johnson & Johnson), one patient Covaxin (Bharat Biotech) and one patient Convidecia (Cansino). In 7 cases the thyroid disorder developed after the third dose with a combination of different vaccines. Regarding the type of thyroid disorder, 59 were subacute thyroiditis (SAT), 29 Graves' disease (GD), 2 co-occurrence of SAT and GD, 6 painless thyroiditis (PT), and single cases of thyroid eye disease and hypothyroidism associated with mixedema. The timeline between vaccination and thyroid disorder ranged between 0.5 to 60 days, with an average of 10.96 days. Considering the limited follow-up time, a complete remission was reported in most of SAT and PT cases while a persistence was observed in GD. In conclusion, both size and quality of published data about thyroid inconveniences after COVID-19 vaccination are limited; thyroid disorders may occur within 2 months after COVID-19 vaccination; among all thyroid diseases after COVID-19 vaccination, GD and SAT seem to be more frequent.