Subclinical hyperthyroidism with multiple nodular goiter

Multinodular goiters was noted in our hospital in Sep. She did not compalined of any discomfort. Although operation and RAI will reduce the size of goiter and relieve symptoms, these treatment should be discussed with the patient first.

Autonomously functioning thyroid adenomas and multinodular goiters are the most common causes of endogenous subclinical hyperthyroidism. The LAB may be normal on retesting weeks or months later, so that intervention should not be considered unless persistently low TSH is noted.

Overt hyperthyroidism is associated with increased bone resorption, low bone density, and an increase in fracture. Patients with subclinical hyperthyroidism also have an increased risk of atrial fibrillation and have more subtle cardiac findings(increases in heart rate, cardiac contractility, and left ventricular mass). In patients at high risk for skeletal or cardiac complications, if the serum TSH <0.1 mU/L, we treat the underlying cause of subclinical hyperthyroidism. If the serum TSH is 0.1 to 0.5 mU/L, we suggest treatment if there is underlying cardiovascular disease or if the bone density is low or the radionuclide scan shows one or more focal areas of increased uptake. For patient with low risk for cardiac or skeletal complications with TSH <0.1 mU/L, we suggest treatment if the radionuclide scan shows one or more focal areas of increased uptake.

Thyroid echo was just preformed on 9/17. Microsomal Ab and TSHR Ab was negative then. There was no FNA data and it was not performed before(according to family statement). Thus, you may arranged aspiration cytology this time and recheck thyroid function later. However, the patient's will of invasive evaluation is not high. Please discusse with her and her family first.

Besides, Amiodarone may also cause mild Hyperthyroidism (3% to 10%). ARB may exaggerate CKD and induce hyperkalemia. Please evalute these drugs. You may also check ACTH and Cortisol, renin activity and aldosterone for hyperkalemia evalulation. Nephrologist may be consulted  if necessary.