Endocrine Abstracts

High dose intravenous methylprednisolone therapy is used in patients with severe thyroid-associated ophthalmopathy (TAO) and other inflammatory disorders. Although in the short-term it appears to be safe, the acute metabolic effects of this regimen have not been studied in detail.
We studied 15 patients with severe TAO, aged 59 ± 10 (mean ± SD) years. One patient was known to have type 2 diabetes. Each patient received 500 mg of iv methyprednisolone daily on three consecutive days, and oral potassium supplements.
Serum TSH declined on day 3 and 2 compared to day 1 (0.57 ± 0.36 nmol/l, 1.01 ± 0.67 nmol/l and 1.97 ± 0.97 nmol/l respectively, p <0.05). Serum total T3 was significantly lower on day 3 and 2 compared to day 1 (1.10 ± 0.37 nmol/l, 1.31 ± 0.36 nmol/l and 1.67 ± 0.54 nmol/l respectively, p < 0.05). Serum free thyroxine did not change. Plasma glucose concentration rose from 5.49 ± 1.58 mmol/l on day 1 to 10.15 ± 2.70 mmol/l on day 2 and 10.34 ± 2.94 mmol/l on day 3. Serum sodium and potassium did not change. Serum urea increased significantly (8.0 ± 1.5 mmol/l, 6.66± 1.25 mmol/l and 5.62 ± 1.35 mmol/l on day 3, 2 and 1 respectively, p < 0.05). Total WBC increased during methylprednisolone therapy (8.0 ± 2.8, 12.0 ± 4.1, 14.4 ± 5.2 on days 1, 2 and 3 respectively). Haemoglobin and platelet counts did not change.
The acute effects of high dose steroids include a decline in serum TSH and total T3 concentrations, presumably due to inhibition of peripheral iodination, and rise in plasma glucose, urea and peripheral white count.