Case report of subacute thyroiditis following SARS-CoV-2 infection

Abstract

INTRODUCTION: SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) is a singlestranded RNA virus with an envelope that causes COVID-19 infection. The disease can be accompanied by mild cold-like symptoms, but it can also have potentially severe complications, some of which can be fatal. According to recent data, the virus can also be one of the causes of subacute thyroiditis (SAT). According to available data, the period of symptom manifestation of thyroiditis (SAT) after recovering from Covid-19 infection is 29 days. The disease may pass through stages of hyperthyroidism, hypothyroidism, and then return to a euthyroid state. In 10% of cases, permanent hypothyroidism may occur, requiring levothyroxine therapy. Treatment is usually symptomatic with high doses of aspirin at 600mg 3-4 times a day or nonsteroidal anti-inflammatory drugs. Corticosteroid therapy is introduced in more severe cases. CASE REPORT: A 69-year-old female patient presented to the Covid outpatient clinic complaining of weakness, fatigue, diarrhea, difficulty swallowing, and low-grade fever around 37.5°C. In her personal history, the patient reported being treated for Hashimoto's multinodular goiter with levothyroxine replacement therapy. She tested negative for the SARS-CoV-2 virus with a rapid antigen test and subsequently had a positive PCR test of the nasopharyngeal swab. An antibiotic, cefixime 400mg once daily, was initiated along with other therapy. After three days, her symptoms worsened. She experienced intense pain in the front of the neck, difficulty swallowing, a feeling of a lump in the throat, dry cough, and a body temperature reaching 38.5°C in the evening and at night. On physical examination, a slightly swollen neck was observed, and deeper palpation revealed the thyroid gland as hard and tender. The antibiotic was changed to azithromycin 500mg and ibuprofen 800mg daily. After 15 days, the patient achieved complete clinical recovery, indicating resolution of viral thyroiditis. Hormonal status remained normal throughout, and she was well substituted with levothyroxine. CONCLUSION: General practitioners should be aware of this complication of COVID-19 disease and analyze thyroid hormone levels in their clinics. Due to the population's exposure to the SARS-CoV-2 virus, subacute thyroiditis should be considered in general practice clinics. Suspicion should arise if fever persists, neck pain worsens, and inflammatory markers persist. Laboratory tests, thyroid hormone analysis, and consultation with an endocrinologist or nuclear medicine specialist should be sought as soon as possible.