What is the differential for elevated T3 (with suppressed T4 and normal TSH) in a patient not taking any thyroid hormones?

This patient has a low to low normal TSH, with weight loss and fatigue so I would approach this as mild hyperthyroidism, or T3 thyrotoxicosis. Sertraline has been associated with abnormal TFTs, usually an elevated TSH and low T4, not with increased T3 levels.

Assess the patient for any other sympto...