Effects of covid-19 infection on thyroid functions

COVID-19 may affect many endocrine tissues as well as thyroid gland and hypothalamus-pituitary-thyroid axis. It has been shown that COV D-19 infection suppresses thyroid hormones in some studies and causes subacute thyroiditis in the others so that its effects are still not fully known. The aim of our study is to retrospectively evaluate thyroid functions, clinical findings, biochemical and inflammatory markers in PCR positive patients infected with COVID-19; and to evaluate the relationship between abnormal thyroid function tests (TFT) and clinical and laboratory findings and whether it has potential prognostic significance.

The data of patients aged 18 years and older, 201 patients who applied to Mersin City Training and Research Hospital due to COVID-19 infection between 1st of March and 1st of April in 2021 and received inpatient treatment were evaluated retrospectively.

Large TFT (TSH, T3, T4, anti-TPO) and laboratory data of 201 patients with mild, moderate or severe pneumonia on CT were scanned retrospectively. 121 (60.2%) of the patients were male, mean age was 51.9 ± 14.6 years, and the most common comorbid disease was hypertension in 65 (32.3%) patients.

It has been determined that the deterioration in TFTs is associated with LDH and D-dimer which are indicators of cell and endothelial damage, duration of hospitalization, clinical severity, and having mutant strains and it has been concluded that low TSH can be used as a prognostic indicator in COVID-19 patients. Further studies with healthy control groups, quantitative RT-PCR tests, histological and pathological correlations, and long-term follow-up are needed.