Complementary markers for the clinical severity classification of hereditary spherocytosis in unsplenectomized patients

Hereditary spherocytosis (HS) is usually classified as mild, moderate or severe using conventional features, namely, hemoglobin (Hb) concentration, reticulocyte count and bilirubin levels, which do not always contribute to an adequate clinical classification. The aim of our study was to establish the importance of some laboratory routine parameters, as markers of HS clinical outcome, by studying a control group (n = 26) and unsplenectomized HS patients (n = 82) presenting mild, moderate or severe HS. We performed a basic hematologic study and evaluated the reticulocyte count, bilirubin, erythropoietin (EPO) and soluble transferrin receptor (sTfR) levels; the osmotic fragility (OFT) and criohemolysis tests (CHT); the ratios Hb/MCHC (mean cell hemoglobin concentration), Hb/RDW (red cell distribution width) and MCHC/RDW, were calculated.Hb changed significantly in accordance with HS severity, but not reticulocytes or bilirubin. We found that MCHC, RDW, EPO, sTfR, OFT, CHT and the calculated ratios were significantly changed in patients, and, therefore, were valuable as complementary diagnostic tools for HS. Moreover, RDW, Hb/MCHC, Hb/RDW and MCHC/RDW changed significantly with worsening of HS; thus, they are also good markers for the clinical outcome of HS. In conclusion, we propose the use of these routine parameters as useful to complement the analysis of HS severity.