Abstract
1. The sequence of characteristic changes of progressive iron deficiency was demonstrated by serial bleeding of normal volunteers and polycythemic patients.
2. After bloodletting, changes occurred in peripheral blood in the following order: a) fall in hemoglobin concentration; b) decreased plasma iron; c) reticulocytosis, increased MCV and MCH; d) diminution of MCV and MCH, increased total iron-binding protein; and e) decreased MCHC.
3. Characteristic changes of iron deficiency returned to prephlebotomy levels in the following sequence: a) hemoglobin concentration; b) cellular indices; c) serum iron; d) serum iron binding protein; and e) bone marrow hemosiderin, and finally the increased gastrointestinal absorption of iron reverted to normal.
4. Accelerated production of red cells continued in polycythemic patients despite the induction of moderate iron deficiency. Quality was sacrificed for quantity, and thereby a more profound microcytosis occurred than in normal subjects with a similar degree of iron deficiency.
