The co-occurrence of SAT, hypophysitis, and Schnitzler syndrome after COVID-19 vaccination: the first described case.

Subacute thyroiditis (also known as granulomatous thyroiditis, giant cell thyroiditis, de Quervain's disease, or SAT) is an inflammatory disease of the thyroid gland, usually spontaneously remitting, that lasts for weeks to months. However, recurrent forms sometimes occur which may have a genetic basis. In our paper, we have focused on the pathogenetics, symptoms, and treatment of SAT. We have described the 17-month disease course of a woman with persistent recurrent steroid-resistant SAT. SAT was well established and the patient's symptoms were not only recurrent neck pain with fever, but also recurrent chronic urticaria, which are symptoms that fulfil the criteria for the diagnosis of Schnitzler syndrome. Schnitzler syndrome occurred after vaccination with COVID-19 in the mechanism of ASIA syndrome. In our patient, Schnitzler syndrome involved the thyroid gland, causing persistent subacute thyroiditis, and the pituitary gland, causing transient swelling of the pituitary, which, to our knowledge, is the first reported case in the literature. Also unprecedented, as far as we know, is the fact that we performed thyroidectomy in the above patient, which reduced systemic inflammation and caused SAT to resolve, although only the inclusion of anakinra treatment resulted in resolution of the underlying condition.