Tumor-Induced Osteomalacia

de Beur, Suzanne M. Jan MD

Contributing Editor, JAMA.
Department of Medicine, Johns Hopkins University School of Medicine, and Department of Endocrinology, Johns Hopkins Bayview Medical Center, Baltimore, Md.

Corresponding Author: Suzanne M. Jan de Beur, MD, Johns Hopkins University School of Medicine, Johns Hopkins Bayview Medical Center, 4940 Eastern Ave, B114, Baltimore, MD 21224 ([email protected]).

Financial Disclosures: None reported.

Funding/Support: This work was sponsored by National Institutes of Health grants R03DK0602944 and K08DK02652.

Role of the Sponsor: The sponsor did not contribute to the design, collection, management, analysis, or interpretation of the data or preparation, review, or approval of the manuscript.

Acknowledgment: I thank my patient for sharing her story and reviewing the manuscript. I am grateful to David Hellmann, MD, Johns Hopkins University School of Medicine, for helpful suggestions for improving the manuscript.

JAMA: The Journal of the American Medical Association 294(10):p 1260-1267, September 14, 2005.

Tumor-induced osteomalacia (TIO) is a rare paraneoplastic form of renal phosphate wasting that results in severe hypophosphatemia, a defect in vitamin D metabolism, and osteomalacia. This debilitating disorder is illustrated by the clinical presentation of a 55-year-old woman with progressive fatigue, weakness, and muscle and bone pain with fractures. After a protracted clinical course and extensive laboratory evaluation, tumor-induced osteomalacia was identified as the basis of her clinical presentation. In this article, the distinctive clinical characteristics of this syndrome, the advances in diagnosis of TIO, and new insights into the pathophysiology of this disorder are discussed.