Covid can cause atypical thyroid inflammation: Study

The study, presented virtually at ENDO 2021, indicated that one-third of the participants still had signs of thyroid inflammation after three months, even though their thyroid function had normalised.

In spring 2020, 15 per cent of the Covid-19 patients hospitalised in acute medicine units in Italy had thyroid hormone alterations due to multi-factorial causes, including thyroid inflammation. In comparison, only 1 per cent of hospitalised patients during the same period in 2019 had thyroid hormone alterations.

"People with thyroiditis, or inflammation of the thyroid gland, triggered by other viruses usually recover thyroid function in the short term," said lead researcher Ilaria Muller from the University of Milan in Italy.

"However, there is a long-term increased risk of permanently reduced thyroid function, caused by late-onset effects of viral infection, or by the immune system attacking the thyroid gland," Muller added.

For the study, the team wanted to find out whether the thyroiditis associated with SARS-CoV-2, the virus that causes COVID-19 disease, follows the same pattern as thyroid inflammation caused by other viruses.

The researchers started a surveillance programme to monitor the thyroid function of patients every three months after being hospitalised for moderate to severe Covid-19 disease. The patients undergo a routine blood and ultrasound testing to monitor their thyroid function and signs of inflammation.

They found the thyroiditis in people with moderate to severe Covid-19 disease differs from typical thyroiditis in several ways, the researchers said.

These include the absence of neck pain, the presence of mild thyroid dysfunction, higher frequency among men and the association with severe Covid-19 disease, they added.