Endocrine Abstracts

31 years old lady with no past medical history or family history of thyroid disease had her first dose of Pfizer vaccine and few days later she presented unwell, Febrile with painful swelling in the neck. She was thought to have Covid because of fever. Examination revealed tender thyroid enlargement with positive bruit and Tachycardia. Investigations showed florid thyrotoxicosis with TSH: < 0.02, fT4: 60.0, CRP: 60, rest of investigation: normal, TRab and TPO AB: pending, Covid PCR: negative repeatedly. Thyroid USS: inflamed thyroid with increased vascularity. She was diagnosed as subacute thyroiditis and started on steroids with follow up in clinic. TRab and TPO ab were negative further confirming the diagnosis. The patient improve on prednisolone both clinically and biochemically. TFT started to normalize. She was reviewed in clinic 2 months later in good conditions with no symptoms. She was successfully weaned off steroid. Discussion: Subacute thyroiditis is a common condition that can occur for many reasons like post viral upper respiratory tract infection, postpartum and autoimmune (Hashimoto’s). It is common among females. It has been documented to happen after administration of inactivated vaccine or live attenuated vaccine like influenzas vaccine and Hepatitis B vaccine. There are 2 cases of subacute thyroiditis which have been reported post SARS-CoV-2 vaccination with Spikevax (Moderna Biotech, Spain) and Vaxzevria (AstraZeneca; Sweden) respectively and one case of Pfizer-biontech vaccine induced thyroiditis. It was thought to be a less likely possibility to happen with Pfizer as it is an mRNA vaccine. Learning: Consider Subacute thyroiditis in patient after SARS-CoV-2 vaccination. The disease tends to run a benign course with rapid recovery. It is steroid responsive. Patients might end up in hypothyroid status. More studies should be carried to insure less occurrence of this side effects. The vaccine should still be used given the fact of how can covid pneumonia be serious in comparison to the potential side effect that will happen in few patients.