Potential utility of the new Sysmex XE 5000 red blood cell extended parameters in the study of disorders of iron metabolism.
BACKGROUND
New erythrocyte parameters are reported by the Sysmex XE 5000 analyzer. This instrument measures the hemoglobin (Hb) content of individual red cells, calculates the percentage of hypochromic red cells (%Hypo He) and the percentage of hyperchromic red cells (%Hyper He) and quantifies the proportion of marginally sized erythrocytes (%Micro R and %Macro R). The goals of the study were to establish the reference range for erythrocyte extended parameters, their value in different types of anemia and to investigate their reliability in the study of disorders of iron metabolism.


METHODS
Three hundred and ninety samples were analyzed. The Kolmogorov-Smirnoff test, independent samples t-test and Pearson correlation were calculated; receiver operating characteristic (ROC) curve analysis was used to determine their diagnostic performance.


RESULTS
The values of the four parameters studied were normally distributed and statistically different (p<0.0001) in the different groups of patients; the only exception was %Hypo He in cases of iron deficiency and thalassemia (p=0.3758). Results of ROC curve analysis for %Hypo He in the diagnosis of restricted erythropoiesis reticulocyte Hb content (reticulocyte hemoglobin content, Ret He <29 pg) were: area under the curve 0.963; cut-off 1.8%; sensitivity 98.3%; specificity 91.1%.


CONCLUSIONS
The new parameters appear to be sensitive for detecting small changes in the number of red cells with inadequate hemoglobinization and volume.
Urrechaga
Eloísa
E
Hematology Laboratory, Hospital Galdakao, Usansolo, Galdakao, Vizcaya, Spain. eloisa.urrechagaigartua@osakidetza.net
Borque
Luís
L
Escanero
Jesús F
JF
D018798:Anemia, Iron-Deficiency / Q000175:diagnosis; D004906:Erythrocyte Count; D004912:Erythrocytes / Q000473:pathology*; D005434:Flow Cytometry / Q000295:instrumentation / Q000379:methods*; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D019189:Iron Metabolism Disorders / Q000175:diagnosis*; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D006454:Hemoglobins