The Usefulness of Blast Flags on the Sysmex XE-5000 Is Questionable.
ABSTRACT Hematology analyzers generate suspect flags that involve microscopic reviews to confirm the presence of pathologic cells. This study investigated the reliability of the blast flag in a side-by-side evaluation of 3 Sysmex XE-5000 instruments (Sysmex, Kobe, Japan). The repeatability of the Q values reported by each instrument for 10 replicates of the same blood samples was low (intraclass correlation coefficient [ICC] values, 0.62-0.74). The reproducibility of the Q values obtained by analyzing 408 samples on all 3 instruments was reasonable (ICC value, 0.85). In addition, a systematic difference was observed among the instruments in the level of reported Q values. With cutoff commonly being 100, the observed reproducibility of the blast flagging among the instruments was evaluated as poor (κ = 0.73). Based on the observed low performances, we question the usefulness of the Q value as a predictor of blasts and whether a blast flag reported by the XE-5000 is sufficient as a criterion for performing a microscopic review.
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ABSTRACT: The usefulness of the CytoDiff flow cytometric system (Beckman Coulter, USA) has been studied in various conditions, but its performance including rapidity in detecting and counting blasts, the most significant abnormal cells in the peripheral blood, has not been well evaluated. The objective of this study was to evaluate the performance of the CytoDiff differential counting method in challenging samples with blasts. In total, 815 blood samples were analyzed. Samples flagged as "blasts" or "variant lymphocytes" and showing <10% blasts by manual counts were included. In total, 322 samples showed blasts on manual counts, ranging from 0.5% to 99%. The CytoDiff method was performed by flow cytometry (FC500; Beckman Coulter, USA) with a pre-mixed CytoDiff reagent and analyzing software (CytoDiff CXP 2.0; Beckman Coulter). The average time required to analyze 20 samples was approximately 60 min for manual counts, and the hands-on time for the CytoDiff method was 15 min. The correlation between the CytoDiff and manual counts was good (r>0.8) for neutrophils and lymphocytes but poor (r<0.8) for other cells. When the cutoff value of the CytoDiff blast count was set at 1%, the sensitivity was 94.4% (95% CI; 91.2-96.6) and specificity was 91.9% (95% CI; 89.0-94.1). The positive predictive value was 88.4% (95% CI; 84.4-91.5) (304/344 cases) and negative predictive value was 96.2% (95% CI; 93.9-97.7) (453/471 cases). The CytoDiff blast counts correlated well to the manual counts (r=0.9223). The CytoDiff method is a specific, sensitive, and rapid method for counting blasts. A cutoff value of 1% of at least 1 type of blast is recommended for positive CytoDiff blast counts.Annals of Laboratory Medicine 01/2015; 35(1):28-34. · 1.48 Impact Factor
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ABSTRACT: The Sysmex XE-5000 instruments (Sysmex, Kobe, Japan) count immature granulocytes (IGs) and use the "Imm Gran?" flag to signal unreliable results. This study investigated the usefulness of the "Imm Gran?" flag and the analytical and diagnostic performance of the IG measurements in a side-by-side evaluation.American Journal of Clinical Pathology 10/2014; 142(4):553-60. · 2.88 Impact Factor
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ABSTRACT: Abstract Background: The Sysmex XN (XN) modular system (Sysmex, Kobe, Japan) is a new automated hematology analyzer equipped with different principles from its previous version, Sysmex XE-2100. We compared the performances of Sysmex XN and XE-2100 in umbilical cord blood (CB) specimens. Methods: In 160 CB specimens, complete blood count (CBC) parameters and white blood cells (WBC) differentials were compared between the two analyzers. Their flagging performances for blasts, abnormal/atypical lymphocytes, immature granulocytes and/or left-shift (IG), and nucleated red blood cells (NRBC) counts were compared with manual counts. For the blast flagging, Q values by Sysmex XN were further compared with manual slide review. Results: Sysmex XN and XE-2100 showed high or very high correlations for most CBC parameters but variable correlations for WBC differentials. Compared with XE-2100, XN showed significantly different flagging performances for blasts, abnormal/atypical lymphocytes, and IG. The flagging efficiency for blasts was significantly better on Sysmex XN than on XE-2100 (85.0% vs. 38.8%): Sysmex XN showed a remarkably increased specificity of blast flag, compromising its sensitivity of blast flag. Among the 24 specimens with blasts (range, 0.5%-1.5%), only one (4.2%) showed a positive Q value. Conclusions: This study highlighted the remarkable differences of flagging performances between Sysmex XN and XE-2100 in CB specimens. The Sysmex XN modular system seems to be a suitable and practical option for the CB specimens used for hematopoietic stem cell transplantation as well as for the specimens from neonates.Clinical Chemistry and Laboratory Medicine 06/2014; · 2.96 Impact Factor