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

Abstract

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.

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

“…Among the post-vaccination new-onset endocrine disorders, subacute thyroiditis (SAT), with several hundred published cases, has been the most reported in the literature. Most reviewed studies demonstrate similarities between post-vaccine SAT and the classic disease regarding diagnosis, clinical course, and outcomes [48,49]. The underlying pathophysiology is an inflammatory process that causes the destruction of follicular epithelium and may be triggered by an immune response following vaccination.…”

“…Noteworthy, no triggering effects other than COVID-19 vaccination with mRNA vaccine, were identified before significant deterioration of stable thyroid eye disease. GD onset or recurrence concurrently with new onset of GO following SARS-CoV-2 mRNA vaccination was described [45][46][47][48][49][50][51][52][53][54][55][56][57]. New-onset thyroid eye disease after COVID-19 vaccination was also reported in a patient with GD relapse treated with radioactive iodine 9 months before vaccine administration [84].…”

“…Another case series compared the clinical features of SAT between 16 vaccinated and 39 non-vaccinated patients and found no differences in diagnosis and clinical course [48]. Finally, a multicenter retrospective cohort study compared SAT clinical parameters and outcomes in 258 patients with post-vaccine SAT to patients with classical SAT and showed a similar disease course [49].…”

Malignant Pseudothyroiditis after COVID-19 Infection Revealing a Poor-Cellular Variant of a Thyroid Anaplastic Carcinoma

“…Given the workup previously performed on this nodule, the probability of malignancy was negligible enough not to incriminate it. The chronology of events has also prompted us to question the role played by COVID-19 infection: no link has ever been described or proposed between thyroid carcinogenesis and viral infection (with COVID-19 or any other virus) [13][14][15][16] and the time to onset does not seem consistent to support the hypothesis of an initiating role. We can also raise the hypothesis of a promoting role of thyroiditis: is it thyroiditis that triggered rapid growth or is it cancer that caused cytolysis?…”