Bimodal distribution of thyroid dysfunction triggered by COVID-19 infection : an experience from a single endocrine center-a case series and literature review

Background: COVID-19 infection has been spreading across the globe since the end of 2019, and it continues to cause chronic multi-system sequelae, of which thyroid dysfunction appears to be the major one. We have discussed here 10 cases of thyroid dysfunction after COVID-19 infection. Methods: Case series report. From October 2020 to July 2021, a series of 10 cases of thyroid dysfunction after COVID-19 infection were recorded and managed in a single outpatient endocrine center in Doha, Qatar. Cases presentation: We have reported 5 cases of Graves's hyperthyroidism, 2 of chronic primary hypothyroidism (including one with Grave's disease [GD]) who was treated through radioactive iodine (RAI) therapy, one case of subacute thyroiditis, one case with "Sick euthyroid disease," and one case of central hypothyroidism. Presently, patients with GD are being treated with carbimazole and those with hypothyroidism are being treated with levothyroxine. The remaining patients had recovered with euthyroid. Conclusion: This is the largest case series reported from a single center to date. The findings of this series indicate a bimodal distribution of thyroid dysfunction in patients with COVID-19 infection. A review of the literature and discussion of potential pathophysiological mechanisms has been presented. We have emphasized the importance of screening for thyroid dysfunction in "post-COVID-19" cases, considering that the prevalence may be underestimated.