THE VALUE OF SHEAR-WAVE ELASTOGRAPHY IN THE DIAGNOSIS AND FOLLOW-UP OF POST COVID-19 SUBACUTE THYROIDITIS

OBJECTIVES: Subacute thyroiditis is a self-limited inflammatory thyroid disease, following or coexisting with a viral infection. COVID-19 has numerous multi-systemic effects, including thyroid disorders. Possible mechanisms involved in thyroid dysfunction associated with COVID-19 infection include apoptosis, inflammatory reaction and follicular cells damage; direct effect of the virus (SARS-CoV-2 genomes were found in patients serum); the interaction with thyroid angiotensin-converting enzyme 2 (ACE2) receptors, respectively MATERIALS: In the period of November 2021-February 2022, five patients with subacute thyroiditis associated with COVID-19 were evaluated in our department (4 women, one man); mean age 42.1±11.3 years. The mean time between COVID-19 infection and onset of subacute thyroiditis was 23±10.2 days. RESULTS: The most common symptoms presented by the affected patients were represented by fever, painful thyroid, and thyrotoxicosis associated complaints. All the patients presented severe inflammatory syndrome, but the thyrotoxicosis clinical and biochemical picture was more severe as compared to other viral subacute thyroiditis. In 60% of the cases, 2D-ultrasonography was suggestive for subacute thyroiditis, but Share-Wave Elastography (SWE) parameters confirmed the diagnostic in 100% of cases (mean thyroid stiffness 234.2±34.5 kPa). Under steroid therapy, during follow-up, the thyroid stiffness decreased gradually at 4 weeks (65.9±15.4 kPa), respectively at 10 weeks (21.6±5.3 kPa). The clinical outcome was favorable in all cases. Two patients developed hypothyroidism and were treated accordingly. Discussions: Subacute thyroiditis are characterized by significantly increased thyroid stiffness. The results of this study documented a significant difference in thyroid tissue stiffness between SAT at baseline and values recorded at the follow-up visit. It is noteworthy that changes in the elastic properties of thyroid parenchyma were associated with a gradual normalization of biochemical parameters CONCLUSIONS: Early diagnosis of subacute thyroiditis associated with COVID-19 is crucial, as prompt treatment with glucocorticoids leads to complete resolution of the disease. Sonoelastography SWE is useful in the positive diagnosis of subacute thyroiditis