Abstract
It is well known that deficiency of vitamin B12 or folic acid results in megaloblastic anemia in post-gastrectomized patients. However, there are some patients who exhibit macrocytic anemia in spite of normal levels of both vitamin B12 and folic acid. This study was conducted to investigate the relationship between the occurrence of anemia and changes in the levels of vitamin B12 binding protein in gastrectomized patients. Anemia was seen in 105 of 151 post-gastrectomized patients and macrocytic anemia was observed in 35 of the 105 patients. Serum levels of vitamin B12-binding protein in the patients with macrocytic anemia were higher than those of normal volunteer controls. This increase was seen even in the patients with normal levels of vitamin B12. Transcobalamin II, the only protein that can transport vitamin B12 into the tissues from the serum, was not decresed, however, the serum levels of holotranscobalamin II, a form of transcobalamin II binding to vitamin B12, was decreased in gastrectomized patients. These results may suggest that functional deficiency of vitamin B12 might be present in the gastrectomized patients even with normal serum levels of vitamin B12.