Clinical determination of the sites of red cell sequestration in hemolytic anemias

The widespread application of red cell survival techniques has revealed the importance of exces-sive red cell destruction in the pathologic physi-ology of many of the anemias. An increasing ar-ray of in vitro methods for detecting red cell or serum abnormalities has provided insight into the in vivo mechanisms underlying some of these proc-esses. In certain disease states the presence of visible or physically measurable alterations of the red cells has permitted detection of the sites and to some extent of the mechanisms of sequestration of these cells. Such valuable observations have been made upon pathologic material from patients with congenital hemolytic anemia (1-5) and sickle cell anemia (1, 5-7). The need has con-tinued to exist, however, for a clinical method by which to determine the sites of red cell destruction, both for an understanding of the relationship be-tween red cell abnormalities and the body's red cell clearing mechanisms, and for pragmatic aid in the often difficult decisions concerning splenec-tomy. The potential usefulness of Na2Cr5104-labelled red cells in the clinical determination of the sites of red cell destruction was suggested to us by ob-servations on postmortem tissues taken from a patient with the hemolytic anemia of liver disease, who succumbed during observation of the sur-vival of Cr5'-labelled autogenous red cells.2 The Crp5 activity of the patient's splenic tissue wa