THU653 Subacute Thyroiditis Following Covid19 Infection

Disclosure: E. Fanous: None. J.G. Karam: None. Background: Subacute thyroiditis is a self-limiting inflammatory condition of the thyroid gland which usually occurs as a post-viral reaction, leading to the destruction of thyroid follicular cells due to infiltration of lymphocytes. During the first outbreak of COVID-19 virus, subacute thyroiditis had been reported as a complication that may occur in patients without any previous thyroid disorder [1]. Clinical Case: A 62-year-old female patient presented with few weeks history of generalized weakness, fatigue, chills, malaise, low appetite, and unintentional weight loss of around 10lbs. She stated that she feels "internal tremors" and palpitations with heart rate increasing from baseline 60 bpm to 90bpm. She had one episode of near syncope at work prompting her presentation. She reports no change in bowel movements, no heat intolerance, no fever or night sweat, no shortness of breath, no visual changes or eyes problems. Five weeks prior to presentation, the patient was diagnosed with COVID-19 infection by PCR, with a mild disease pattern that consisted of upper respiratory symptoms lasting for few days, however she continued to feel fatigue and low appetite since then, attributing her symptoms to long-term sequelae of Coivd-19. Her past medical history is remarkable for obesity, hypercholesterolemia, and two prior Covid 19 infections: in 2020, treated with monoclonal antibodies, and early 2022. The physical exam was significant for slightly tender thyroid and heart rate of 94 bpm. Thyroid function tests were consistent with hyperthyroidism; TSH<0.01mIU/ml, FT4=2.55ng/dl (0.58-1.64), T4=19.6 mcg/dl (4.4-9.5), T3=1.45ng/ml (0.72-1.35), with negative TSI, TPO AB, and TG AB. ESR was 44mm/hr, RAI uptake and scan showed very low uptake which is indicative for subacute thyroiditis. The patient was given supportive therapy. She developed mild and transient hypothyroidism at 6 weeks follow-up with TSH of 8.59 IU/ml and FT4=0.62 ng/dl (0.89-1.76) before her thyroid tests return to normal at 9 weeks with complete resolution of her symptoms. Conclusion: Prolonged diverse symptoms following Covid19 infection are often attributed to long term Covid symptoms. Health Care providers should be aware of the possibility of subacute thyroiditis following Covid 19 infection and should obtain thyroid function tests in patients who present with malaise, decreased appetite, weight loss and palpitations in the weeks following Covid 19 infection. Reference:1. Mattar SAM, Koh SJQ, Rama Chandran S, Cherng BPZ. Subacute thyroiditis associated with COVID-19. BMJ Case Rep. doi: 10.1136/bcr-2020-237336 Presentation: Thursday, June 15, 2023