Imbalance of globin chain synthesis in newborn infants with hemolytic disease after exchange transfusion.

The relative rates of beta-, gamma-, and alpha-globin chain formation in reticulocytes of six newborn infants ,ith hemolytic disease were determined before and in weekly intervals after exchange transfusion. Directly after birth (before exchange transfusion) the beta/alpha, gamma/alpha, and (beta + gamma)/alpha ratios in newborn infants with hemolytic disease (0.35 +/- 0.20, 0.67 +/- 0.12, and 1.06 +/- 0.29) were similar to those of normal newborn infants (0.33 +/- 0.07, 0.65 +/- 0.06, and 0.98 +/- 0.06). The gradual increase in the beta/alpha ratio seen during the postnatal period of eight normal newborn infants was also observed in newborn infants with hemolytic disease after exchange transfusion. In contrast, the gamma/alpha ratio was found to be increased (1.89 +/- 0.25) in all infants with hemolytic disease in the second week after exchange transfusion. The corresponding value for normal newborn infants was 0.48 +/- 0.25. After exchange transfusion the number of hemoglobin F-containing erythrocytes increased. Possible reasohs for this imbalance of globin chain formation after exchange transfusion may be the decreased erythropoiesis and/or the abnormal high hemoglobin A concentration after exchange transfusion or the introduction of an unknown, gamma chain formation-stimulating agent by exchange transfusion. Speculation In newborn infants with hemolytic disease the repression of gamma-globin chain formation normally seen during the postnatal period is replaced by a stimulated gamma-globin chain production after exchange transfusion.