Case Report: De Quervain's Thyroiditis as a Long-Term Sequelae Complication to SARS-CoV-2 Infection

A 44-year-old man presented with an enlarged painful lower anterior neck lump with elevated serum concentrations of free thyroxine (T4) and tri-iodothyronine (T3), alongside the presence of antithyroid peroxidase antibodies. Prior to presentation, the patient was demonstrating recovery from a SARS-CoV-2 infection that required sedation, intubation, and invasive ventilation in the intensive care unit (ICU) for 11 days. Ultrasound examination of the thyroid demonstrated features of De Quervain's (subacute) thyroiditis. This corresponded to the clinical picture, and continuous thyroid function tests were arranged. Emerging evidence throughout the SARS-CoV-2 pandemic describes the long-term sequelae of the infection, including developing atypical effects on the thyroid gland. This case report emphasises the association of painful subacute thyroiditis with post-viral infection and its manifestation during recovery from severe SARS-CoV-2, suggesting that follow-up thyroid function testing should be considered in patients discharged from the ICU who develop neck discomfort.