Endocrine Abstracts

Background: Recently, clinical evidence of thyroid dysfunction has been observed both in acute and post-COVID period. The aim of this study was to estimate the serum TSH level in hospitalized patients with moderate-to-severe COVID-19.

Methods: It was a single-center study conducted by the Almazov National Medical Research Centre (Russian Federation). Patients hospitalized with detected SARS-CoV-2 infection by RT-PCR test and chest computed tomography (CT) were enrolled. We did not include patients with a medical history of thyroid disease. Clinical data, laboratory tests (TSH at the 1^st and at the 9^th day of hospitalization; C-reactive protein, lactate dehydrogenase and ferritin levels at the 1^st day of hospitalization), CT data and received systemic corticosteroid therapy were analyzed.

Results: A total of 77 patients with an average day of illness at the time of hospitalization 8 ± 1.2 days were included. The baseline abnormal TSH level (<0.4 mIU/l) was found in 4 patients (5.2%), while by the 9th day of hospitalization their number doubled and reached 9 (11.7%). Furthermore, we found that by the 9th day the TSH level more than 4.5 mIU/l was detected in 4 patients (4.2%). Thus, 13 out of 77 (16.9 %) patients had the abnormal serum TSH level by the 9th day. No statistically significant correlations with the TSH level of the C-reactive protein, lactate dehydrogenase and ferritin levels was detected in our study (P> 0.05). Also we did not find any correlations with the TSH level of the CT degree and of the clinical severity (P> 0.05). There was no any difference in average daily glucocorticoid dose among patients with abnormal TSH level and without it.

Conclusions: Abnormal TSH level could be explained by the function alterations of the hypothalamic-pituitary-thyroid axis associated with SARS-CoV-2. Future studies may clarify pathogenic aspects of thyroid dysfunction caused by COVID-19.