Reticulocyte crisis after splenectomy: evidence for delayed red cell maturation?

In whole blood from splenectomized subjects (n = 8) in a steady state an increased number of reticulocytes was observed (14.0 +/- 7.8% versus 3.6 +/- 2.4% controls: p less than 0.05). Cell fractionation on density showed that reticulocytes, as in normals, are more or less confined to the least dense fraction; cell fractionation on volume revealed that reticulocytes form a heterogeneous cell population with diverging volume, but sharing a low density. Immediately after splenectomy (n = 4), a reticulocytosis is observed, mainly manifest in the top fractions (262.0 +/- 49.0% versus 40.0 +/- 32.4% preoperatively; p less than 0.01). This reticulocytosis is not due to pre- or postoperative complications, but is associated with the splenectomy itself and probably is the consequence of a delayed, but ultimately occurring red cell maturation. The increase of reticulocytes is not accompanied by significant alterations in cell morphology, as far as cell volume is concerned.