A case of Post-COVID-19 thyrotoxicosis and a cavalcade of complications

ABSTRACT

Thyroid dysfunction has been reported following COVID-19 infection in the recent past. A 50 year old hypertensive female with no previous thyroid illness, developed features of thyrotoxicosis two weeks after a COVID-19 infection. There was no thyromegaly, neck pain or fever and her ESR was 15 mm/hour. She was initiated on propranolol and methimazole in an outside hospital. Ten days later, she presented to our hospital with fever, sore throat, cough and breathing difficulty. On evaluation she was found to be in neutropenic sepsis (WBC -820 cells/mm3, ANC-6 cells/mm3). Evaluation of thyroid functions showed TSH- <0.00025 IU/ml, free T3 - 4.17 pg/ml, free T4- 3.59 ng/ml and Thyroid Receptor Antibody Levels (TRAb)- 2.53 IU/L. Following treatment with colony stimulating factors and antibiotics she recovered. The patient was commenced on lithium bicarbonate and cholestyramine, along with propranolol. On follow up in the OPD she is euthyroid with free T4 1.43 ng/ml (normal) levels. Post COVID-19 thyrotoxicosis in this case is likely due to Graves' disease. Thyrotoxicosis following COVID-19 is now being recognised and is possibly due to infection induced molecular mimicry with activation of immune pathways causing autoimmune disorders.