24-25-dihydroxyvitamin-d-3 and Crohn-Disease

A forearm counter and double-isotope technique were used to measure intestinal calcium absorption in 21 patients after jejuno-ileal bypass for obesity or small intestinal resection. In all but 2 patients calcium absorption was below the normal range for 10 male controls. 3 weeks treatment with 1-alpha-hydroxyvitamin D, 1 microgram b.d., or 1,25-dihydroxyvitamin D, 1 microgram b.d., was associated with significant increases in absorption whereas 3 weeks treatment with 24,25-dihydroxyvitamin D had no effect. This study demonstrates that oral 1,25-dihydroxyvitamin D or 1-alpha-hydroxyvitamin D are effective in increasing calcium absorption.

Topics: 24,25-Dihydroxyvitamin D 3; Adult; Calcifediol; Calcitriol; Calcium; Crohn Disease; Dihydroxycholecalciferols; Female; Humans; Intestinal Absorption; Intestine, Small; Jejunoileal Bypass; Male; Middle Aged; Obesity; Reference Values

Forty patients with Crohn's disease were divided into undernourished (18) and well nourished (22) groups depending on whether their midarm circumference was below or above 90% of the ideal standard. Plasma 25-(OH)D3 and the dihydroxylated metabolites, 24,25-(OH)2D3 and 1,25-(OH)2D3 were measured in the summer. Results were related to clinical and biochemical parameters and also compared with results from patients with ulcerative colitis and healthy subjects who served as controls. Plasma 25-(OH)D3 was reduced in the undernourished Crohn's group compared with the well nourished Crohn's group, who did not differ from the controls. Over 50% of the undernourished Crohn's group had evidence of secondary hyperparathyroidism and raised alkaline phosphatase concentrations, although concentrations of 1,25-(OH)2D3 were normal. The low 25-(OH)D3 concentrations related to disease activity. It is suggested that undernourished Crohn's patients who have high levels of disease activity are at risk of vitamin D deficiency, and attempts should be made to improve their vitamin D nutrition.

Topics: 24,25-Dihydroxyvitamin D 3; Adolescent; Adult; Aged; Alkaline Phosphatase; Anthropometry; Calcifediol; Calcitriol; Colitis, Ulcerative; Crohn Disease; Dihydroxycholecalciferols; Female; Humans; Hydroxycholecalciferols; Male; Middle Aged; Nutritional Physiological Phenomena; Orosomucoid; Vitamin D

Thirty-six unselected patients were investigated 3-24 years (mean, 7.8 years) after small-bowel resection for Crohn's disease (mean small intestinal resection, 105 cm). Iliac crest bone biopsies after in vivo tetracycline double-labelling showed a markedly reduced trabecular bone mass (controls, 0.25 +/- 0.06; patients, 0.15 +/- 0.05; p less than 0.01). The average bone remodeling and osteoid mineralization was normal, and only two patients demonstrated signs of frank but slight osteomalacia. The mean serum levels of the three vitamin D metabolites 25-hydroxyvitamin D, 24,25-dihydroxyvitamin D, and 1,25-dihydroxyvitamin D were normal. The observed reduction in trabecular bone mass may theoretically be followed by an increased risk of spontaneous fractures.

Topics: 24,25-Dihydroxyvitamin D 3; Adult; Aged; Bone and Bones; Calcifediol; Calcitriol; Crohn Disease; Dihydroxycholecalciferols; Female; Humans; Intestine, Small; Male; Middle Aged; Photometry; Postoperative Complications; Tetracycline; Vitamin D