Reduced Serum Levels of Iα, 25-Dihydroxyvitamin D During Long-term Total Parenteral Nutrition

doi:10.1059/0003-4819-94-5-638

Reduced Serum Levels of Iα, 25-Dihydroxyvitamin D During Long-term Total Parenteral Nutrition

Los Angeles, California; Ames, Iowa; Riverside, California; and St. Louis, Missouri

Abstract

Painful bone disease, characterized by patchy osteomalacia and inactive bone, can develop in patients treated with total parenteral nutrition for more than 3 months. Serum levels of 1α, 25-dihydroxyvitamin D (1α, 25(OH)₂D), 24,25-dihydroxyvitamin D and 25-hydroxyvitamin D were measured in seven adults and five children treated with parenteral nutrition for 9 to 60 months. Serum levels of 1α,25(OH)₂D were markedly reduced, while levels of 25-hydroxyvitamin D and 24,25-dihydroxyvitamin D were normal. Serum calcium and phosphorus levels were normal or slightly increased, and immunoreactive parathyroid hormone levels were normal or low. Renal function was normal or minimally reduced. Skeletal symptoms disappeared and serum 1α,25(OH)₂D levels rose to normal in one patient when nutrient infusions were discontinued for 6 weeks. Removal of calcium from the nutrient solution for 2 to 4 days was associated with no change in serum 1α,25(OH)₂D in two patients. The cause of the reduction in serum levels of 1α,25(OH)₂D and its role in the pathogenesis of bone disease in these patients remain uncertain.

Article and Author Information

▸From the Department of Pediatrics and Medicine, University of California School of Medicine, and the Medical and Research Services, Veterans Administration Wadsworth Medical Center; Los Angeles, California; National Animal Disease Center, Agriculture Research, Science and Education Administration, US Department of Agriculture; Ames, Iowa; the Department of Biochemistry, University of California; Riverside, California; and the Department of Internal Medicine, Washington University School of Medicine; St. Louis, Missouri.
Supported in part by U.S. Public Health Service Grant AM 14750 and RR 865 and Veterans Administration Funds.
▸Requests for reprints should be addressed to Jack W. Coburn, M.D.; Veterans Administration Wadsworth Medical Center, Sawtelle and Wilshire Blvds.; Los Angeles, CA 90073.