Case 1:  A 49-year-old Sudanese gentleman with a history of bronchial asthma, hypertension, prediabetes, and gout tested positive for COVID-19 on November 24, 2020. He underwent polymerase chain reaction testing as mandatory screening, which was performed upon arrival in Qatar as a part of the preventive measures taken to curb the spread of coronavirus. Upon questioning, he provided a history of headache and fever over the preceding few days along with multiple episodes of vomiting and diarrhea (around 4 times a day). The patient denied any cough, shortness of breath, or sore throat. He was diagnosed with COVID-19 pneumonia and was started on the anti-retroviral favipiravir and transferred to a quarantine facility. No thyroid function tests (TFTs) were conducted during this time. He undertook a TFT in May 2019, which was normal. He subsequently made an uneventful recovery from COVID-19. Two months later, the patient undertook a general checkup to complain of a slight increase in body weight. Here, his TFT revealed a thyroid-stimulating hormone (TSH) value of 33.49 mu/L (normal range reference [NRR] 0.4-4.5 mu/L), and a free tbl4 value of 8 pmol/L (NRR 8-18 pmol/L). Repeat TFTs conducted 6 weeks later revealed a TSH value of 34.22 mu/L and the tbl4 value further dropped to 7.4 pmol/L. At this point, he was referred to our endocrine clinic.
When reviewed at our clinic, he denied any history of tiredness, fatigue, sleepiness, or other symptoms of hypothyroidism other than weight gain. He had no family history of goiter or thyroid dysfunction. He was not on any medication that may have caused perturbation of the thyroid functions. On examination, his vital signs were normal. He was clinically euthyroid, with no neck swelling and an unremarkable physical examination. The test results showed TSH 49 mU/L and FT 11 pmol/L. Antithyroid peroxidase antibodies (anti-TPO Ab) were 423 IU/mL (normal < 30) and TSH receptor antibodies TRAb was negative. Neck ultrasound (US) showed heterogeneous thyroid with minimally increased vascularity and a small hyperechoic nodule measuring 5 x 4 mm. The thyroid uptake scan revealed normal morphology and function, except for a cold nodule in the postero-inferior part of the right lobe.
After a discussion with the patient, it was decided to adopt the wait-and-see policy. TFT repeated after 6 weeks showed that the TSH value had risen to 61 mIU/L and FT to 4 pmol/L. He was accordingly started on levothyroxine (100 mcg, daily), and his TFT normalized after 6 weeks.