Background: Hashimoto's thyroiditis (HT), one of the most common autoimmune thyroid diseases (AITDs), is the major cause of hypothyroidism in the world's iodine-sufficient regions. The Severe Acute Respiratory Syndrome Virus 2 (SARS-CoV-2) causes COVID-19 illness, belong to the family of beta-coronaviruses which rapidly spread leading to COVID-19 pandemic on March 11, 2020. Since follicular thyroid cells express the angiotensin converting enzyme 2 (ACE2), the virus's receptor for cellular entry, they may serve as a direct target for SARS-CoV-2 infection.
Objective: The aim of the current work was to evaluate the thyroid function consequences following either (COVID-19) infection or vaccination in group of Hashimoto thyroiditis and normal subjects in relation to their clinical features, biochemical, immunological, and inflammatory markers.
Patients and Methods: This study was conducted on 80 subjects attending the COVID Vaccination Center and Emergency Isolation at Ain Shams University Hospital during the period from August to October 2022, 14 males, and 66 females, their age ranged from 18 to 70 years. They were divided according to thyroid Abs into Hashimoto's thyroiditis group and normal group, each of them divided into 2 subgroups (exposed to COVID 19 infection & got COVID 19 vaccine).
Results: This study showed significant increase in the level of TSH and decrease in the level of free T3, Free T4 in Hashimoto's patients who exposed to COVID19 infection (P-value <0,01). Significant decrease in the level of TSH and increase in the level of free T3, Free T4 in Hashimoto's subjects' group after their exposure to COVID19 vaccine (AstraZeneca) (P-value <0,01), normal subjects group after exposure to COVID19 infection (P-value .02 and <0,01) and normal subjects group after being exposed to COVID19 vaccine (AstraZeneca) (P-value .02 and .04).
Conclusion: COVID19 infection and vaccination against COVID might be followed by an attack of thyroiditis in Hashimoto patients and even in normal persons.