Bone Composition and Vitamin D after Pólya Gastrectomy

Abstract

Partial gastrectomy may expose the patient to intestinal malabsorption with possible vitamin D deficiency and Ca deficiency. With the aim of evaluating bone P/hydroxyproline ratio (P/Hypro) as an index of osteomalacia, this bone index and bone mineral content (BMC) were investigated together with other indices of Ca metabolism in 27 gastrectomized patients. None of the patients had clinically manifest bone symptoms. Mean values of bone P/Hypro, BMC, plasma Ca and plasma Mg were subnormal; mean values of serum parathyroid hormone (iPTH) and plasma alkaline phosphatase were elevated. Mean serum 25-hydroxycholecalciferol (25-OH-D) did not differ from normal. A significant positive correlation was found between bone P/Hypro and serum 25-OH-D but no significant correlation between bone P/Hypro and BMC. Serum 25-OH-D and bone P/Hypro were significantly lower, and serum iPTH was significantly higher in a subgroup of 12 patients with no regular supplementary intake of vitamin D. Gastrectomized patients had blood biochemical evidence of a mild vitamin D insufficiency, and low bone P/Hypro values can be explained by mild osteomalacic changes in bone.