The Importance of Nucleated Red Blood Cells in Patients with Beta Thalassemia Major and Comparison of Two Automated Systems with Manual Microscopy and Flow Cytometry.

BACKGROUND

Nucleated red blood cells (NRBC) can be used as a marker of erythropoietic stress and help optimize transfusion therapy in patients with beta thalassemia major. The aim of this study was to determine this correlation; and compare two automated systems (Sysmex XE-2100, and Advia 2120i) with manual microscopy and flow cytometry (FCM).

METHODS

Absolute NRBC counts and percentages (NRBC%) from 51 patients were analyzed with both automated and reference methods. The results were compared with levels of pre-transfusion hemoglobin and ferritin levels.

RESULTS

The mean age of the included patients (31 female, 20 male) were 12.9 ± 7.5 years. Mean levels of hemoglobin and ferritin were 9.5 ± 1.2 g/dL and 1896 ± 1194 ng/mL respectively. The NRBC% of two instruments did not significantly differ and correlated well (p < 0.0001, r2 = 0.984). NRBC% obtained with the XE-2100 and Advia 2120i versus manual microscopy also yielded high correlations (r2 = 0.951 and r2 0.981, respectively); however, absolute NRBC counts versus FCM yielded lower coefficients (r2 = 0.723 and r2 = 0.694, respectively). High serum ferritin levels were correlated with both NRBC% and counts with both instruments (p < 0.001) and hemoglobin levels lower than 9.0 g/dL had a negative correlation with NRBC% and NRBC counts with the Advia 2120i (p < 0.05, r = -0.495) but not with the XE-2100.

CONCLUSIONS

Monitoring of NRBC% with both instruments can help optimize transfusion therapy for patients with beta thalassemia major. Following the NRBC% is more efficient than absolute counts.