Abstract • Symptomatic osteopenia accompanied by subclinical hyperthyroidism developed in three women who were receiving excess thyroid hormone medication. Excessive thyroid replacement therapy resulted in mild hypercalcemia, hyperphosphatemia, and hyperphosphatasemia associated with diffuse skeletal demineralization and multiple fractures. Nondecalcified sections of double tetracycline-labeled iliac crest bone showed an accelerated rate of bone turnover with marked osteoclastosis and resorption of the cortical as well as the trabecular bone, typical of endogenous hyperthyroidism. Since thyroid hormones are among the most frequently prescribed medications, bone loss caused by exogenous hyperthyroidism may be more common than previously recognized. (Arch Intern Med 1983;143:442-444) References 1. Mosekilde L, Christensen MS: Decreased parathyroid function in hyperthyroidism: Interrelationships between serum parathyroid hormone, calcium-phosphorus metabolism and thyroid function. Acta Endocrinol 1977;84:566-575. 2. Melsen F, Mosekilde L: Morphometric dynamic studies of bone changes in hyperthyroidism. Acta Pathol Microbiol Scand 1977;85:141-150. 3. Jostrup B, Mosekilde L, Melson F, et al: Serum levels of vitamin D metabolites and bone remodeling in hyperthyroidism. Metabolism 1982;31: 126-132.Crossref 4. Brennan MD: Clinical pharmacology: Series on pharmacology in practice: V. Thyroid hormones. Mayo Clin Proc 1980;55:33-44. 5. Riggs BL, Wahner WL, Dunn WL, et al: Differential changes in bone mineral density of the appendicular and axial skeleton with aging. J Clin Invest 1981;67:328-335.Crossref 6. Hruska KA, Kopelman R, Rutherford WE, et al: Metabolism of immunoreactive parathyroid hormone in the dog: The role of the kidney and the effects of chronic renal disease. J Clin Invest 1975;56:39-48.Crossref 7. Cameron JR, Mazess RB, Sorenson JA: Precision and accuracy of bone mineral determination by direct photon beam absorptiometry. Invest Radiol 1960;3:141-150.Crossref 8. Cameron JR, Sorenson JA: Measurement of bone mineral in vivo: An improved method. Science 1963;142:230-232.Crossref 9. Mosekilde L, Melsen F: A tetracycline-based histomorphometric evaluation of bone resorption and bone turnover in hyperthyroidism and hyperparathyroidism. Acta Med Scand 1978;204:97-102.Crossref 10. Whyte MP, Bergfeld MA, Murphy WA, et al: Postmenopausal osteoporosis: A heterogeneous disorder as assessed by histomorphometric analysis of iliac crest bone from untreated patients. Am J Med 1982;72: 193-202.Crossref 11. Mundy GR, Raisz LG: Thyrotoxicosis and calcium metabolism. Mineral Electrolyte Metabol 1979;2:285-292. 12. Howard GA, Bottemiller BL, Baylink DJ: Evidence for the coupling of bone formation to bone resorption in vitro. Metabol Bone Dis Relat Res 1980;2:131-135.Crossref 13. Meema HE, Schatz DL: Simple radiological demonstration of cortical bone loss in thyrotoxicosis. Radiology 1970;97:9-15. 14. Smith DA, Fraser SA, Wilson GM: Hyperthyroidism and calcium metabolism. Clin Endocrinol Metabol 1973;2:333-353.Crossref 15. Cooper DS, Kaplan MM, Ridgway EC, et al: Alkaline phosphatase isoenzyme patterns in hyperthyroidism. Ann Intern Med 1979;90:164-168.Crossref 16. Rhone DP, Berlinger FG, White FM: Tissue sources of elevated serum alkaline phosphatase activity in hyperthyroid patients. Am J Clin Pathol 1980;74:381-386. 17. Melsen F, Mosekilde L: Tetracycline double-labeling of iliac trabecular bone in 41 normal adults. Calcif Tissue Int 1978;26:99-102.Crossref 18. Melsen F, Melsen B, Mosekilde L, et al: Histomorphometric analysis of normal bone from the iliac crest. Acta Pathol Microbiol Scand 1978;86A: 70-81.
Archives of Internal Medicine – American Medical Association
Published: Mar 1, 1983