Unbound Amino Acids in the Plasma and Erythrocytes of Children with Various Anemias and with Erythroblastosis Fetalis

The unbound amino acid concentrations in the plasma and erythrocytes of 24 children with anemias of various types have been determined by the method of salt-saturated paper chromatography (iron deficiency anemia— 8 subjects; sickle cell anemia—3 subjects; hereditary spherocytosis—3 subjects; erythroblastosis fetalis—4 subjects; and 1 subject each for thalassemia minor, thalassemia major, unstable reduced glutathione, acquired hemolytic anemia, autoimmune hemolytic anemia, S & F hemoglobinopathy). Anemia per se was found to have little effect on the plasma amino acid concentrations, although a marked increase in the erythrocyte concentrations of every amino acid determined was found. In multiple regression and correlation analyses, the unbound amino acid concentrations in the erythrocytes were found to be a function of both the reticulocyte counts and the blood hemoglobin content, with a somewhat greater dependence on the latter. No recognizable distinction as to the disease category was evident in the unbound amino acid patterns of the anemia patients. The extent of the unbound amino acid elevations in the erythrocytes was largely a reflection of the severity of the anemia.

The subjects with erythroblastosis fetalis were in a category different from those with anemia. Their erythrocyte amino acid concentrations were probably the same as those of normal babies during the first few hours after birth.