P1550: New Generation Ektacytometry Study of Red Blood Cells Rheological Parameters in Hemoglobinopathies

Congenital Defects with Impaired Red Blood Cell Deformability – The Role of Next-Generation Ektacytometry

“…Despite the osmoscan module not considering the oxygenation of the sample, the possible deoxygenation during the analytical process may explain a partial Hb S polymerisation and, in turn, the increase of red cells dehydration and rigidity [73]. The AUC, which is an important marker of decreased deformability in RBC membranopathies [72], is also decreased in all the haemoglobinopathies studied by us. Carriers for Hb S, Hb C and β-thal show a similar osmoscan profile with an intermediate left shift of the curve and a less decrease of EImax (deformability) at normal osmotic value, suggesting the existence of a less degree of dehydration when compared with Hb SS and HbSC.…”

“…The osmoscan curves from patients with different haemoglobinopathies are shown in Figure 11. They have in common a left shift of both curve tails, suggesting the existence of a different degree of RBCs dehydration depending on the type of haemoglobinopathy [72]. The most severe decrease of EImax and left shift of the osmoscan curve is observed in patients with Hb SS and HbSC, all associated with severe vase-occlusive crises.…”

“…Moreover, Hb D and Hb E show an almost normal osmoscan profile with a slight decrease of EImax and Ohyper in accordance with their low or absent clinical expression. In addition to SCD, HbD, HbC, HbE and HbO-Arab, other structural haemoglobinopathies such as the unstable haemoglobins with intracellular haemoglobin precipitates or Heinz bodies exhibit a CNSHA of variable severity, but unlike SCD, the inheritance has an autosomal dominant pattern [72]. Interestingly, we have recently described one patient with the hyperunstable haemoglobin Bristol-Alesha, associated with severe haemolytic anaemia that exhibited the same OGE profile as β-thalassaemia [74].…”