Along with our case, all 3 previously reported cases were female (ages ranged from 28 to 53 years). No patients had been previously diagnosed with thyroid disease. All patients had had COVID-19 infection with respiratory symptoms. The interval between diagnosis of hyperthyroidism and COVID-19 infection ranged from 0 to 84 days. Like our case, most of these patients manifested a goitre and palpitations. Thyroid function tests showed overt hyperthyroidism. TSH levels were undetectable (<0.01 U/L) and FT4 were 2-3 times higher than upper limit of the normal level (NR27 – 36.5 pmol/L). Thyroid autoantibodies were measured and showed increased TRAb in all cases. Anti -Tg andAnti -TPO were significantly elevated in our case and in that reported by Mateu-Salat [15]. Thyroid ultrasound examinations of these patients were typical for Graves’ disease, with hypervascularity and mild thyromegaly. Iodine uptakes were done in two patients to confirm the diagnosis of hyperthyroidism. Patients were all treated with anti-thyroid medication and clinical improvement resulted.
The major limitation of our case report review is the paucity of published cases (only 3 other patients reported so far). Nevertheless, these reports are likely to be of benefit to clinicians who encounter cases of new-onset hyperthyroidism after COVID-19 infection. From our review, the hyperthyroidism is mild, responds well to methimazole and beta blockers in combination and has a low incidence post COVID-19 infection. A larger case series might confirm these findings Moreover, additional follow-up data are necessary to assess long term outcomes in these cases.