Abnormal Thyroid Function Following COVID-19 Vaccination : Indian Journal of Endocrinology and Metabolism

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Letter to the Editor

Abnormal Thyroid Function Following COVID-19 Vaccination

Mungmunpuntipantip, Rujittika; Wiwanitkit, Viroj1

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Indian Journal of Endocrinology and Metabolism: March–April 2021 - Volume 25 - Issue 2 - p 169
doi: 10.4103/ijem.ijem_286_21
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We would like to share ideas on new evidence of abnormal thyroid function following the COVID-19 vaccination. Lastra et al. noted that Graves’ disease might occur after SARS-CoV-2 vaccination[1] and noted that adjuvants might induce disorder. Recently, there have been some reports on thyroid problems following vaccinations.[12] We agree that the adjuvant might cause alteration of the immune system and cause thyroid problems. Nevertheless, there might also be other possible pathomechanisms. Pathophysiologically, administration of the COVID-19 vaccine results in increased blood viscosity and might cause hyperviscosity.[2] If hyperviscosity occurs, it can result in an aberrantly increased thyroid hormone level.[3] It is interesting to have a further study on thyroid function among healthy and thyroid patients who receive the COVID-19 vaccination.

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1. Lastra OV, Navarro AO, Domiguez MPC, Medina G, Valadez TIS, Jara LJ. Two cases of Graves'disease following SARS-CoV-2 vaccination:An autoimmune/inflammatory syndrome induced by adjuvants Thyroid. 2021 doi: 10.1089/thy. 2021.0142
2. Joob B, Wiwanitkit V. Expected viscosity after COVID-19 vaccination, hyperviscosity and previous COVID-19 Clin Appl Thromb Hemost. 2021;27:10760296211020833
3. Tamagna E, Hershman J, Premachandra BN. Circulating thyroid hormones in a patient with hyperviscosity syndrome Clin Chim Acta. 1979;93:263–8
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