As a result, during acute or chronic inflammation, some cytokines may reduce TSH expression, potentially leading to SH in order to achieve sufficient levels of active thyroid hormone for normal metabolism, and reduce deiodinase type 1 enzyme activity, leading to the biochemical picture of euthyroid sick syndrome (low/normal fT4 and fT3 and elevated rT3). Here, TG is linked to euthyroid sick syndrome.