The anemia of thermal injury: studies of erythropoiesis in vitro.

Anemia is invariably seen in patients who have been severely burned, and a number of factors have been implicated in its etiology. Prior studies have suggested that a depressed rate of erythropoiesis is involved. In order to study this, we evaluated the effect of serum from burned patients on red cell and white cell colony growth in vitro. We found that these sera were capable of inhibiting red cell, but not white cell, colony growth. Additional experiments indicated that this was related to the presence of some substance in the burned serum rather than the absence of a factor required for colony formation. Further studies, including review of clinical data, suggested that this effect was not due to topical medications nor to episodes of bacterial sepsis. Serial studies showed that inhibition was often not present in the immediate postburn period but developed gradually, reaching maximum intensity approximately 20 to 30 days following the burn and then returning toward normal as patients healed their injury. Our studies permit the hypothesis that inhibition of erythropoiesis plays a role in the pathogenesis of the anemia of thermal injury.