Splenectomy does not cure but does ameliorate CNSHA of PK deficiency. In each of these 10 patients with PK deficiency, a significant increase in the steady-state hemoglobin level was seen after splenectomy (left panel). Whereas in most types of CNSHA an improvement of anemia, resulting from decreased hemolysis, is usually associated with a decrease in the reticulocyte count, in PK deficiency reticulocytes often increase after splenectomy. This paradoxical phenomenon suggests that the spleen selectively removes PK-deficient reticulocytes; the mechanism is not yet well understood.⁴⁸  From Zanella et al.⁸