Performance comparison of two automated digital morphology analyzers for leukocyte differential in patients with malignant hematological diseases: Mindray MC-80 and Sysmex DI-60.

BACKGROUND: The MC-80 (Mindray, Shenzhen, China), a newly available artificial intelligence (AI)-based digital morphology analyzer, is the focus of this study. We aim to compare the leukocyte differential performance of the Mindray MC-80 with that of the Sysmex DI-60 and the gold standard, manual microscopy. METHODS: A total of 100 abnormal peripheral blood (PB) smears were compared across the MC-80, DI-60, and manual microscopy. Sensitivity, specificity, predictive value, and efficiency were calculated according to the Clinical and Laboratory Standards Institute (CLSI) EP12-A2 guidelines. Comparisons were made using Bland-Altman analysis and Passing-Bablok regression analysis. Additionally, within-run imprecision was evaluated using five samples, each with varying percentages of mature leukocytes and blasts, in accordance with CLSI EP05-A3 guidelines. RESULTS: The within-run coefficient of variation (%CV) of the MC-80 for most cell classes in the five samples was lower than that of the DI-60. Sensitivities for the MC-80 ranged from 98.2% for nucleated red blood cells (NRBC) to 28.6% for reactive lymphocytes. The DI-60's sensitivities varied between 100% for basophils and reactive lymphocytes, and 11.1% for metamyelocytes. Both analyzers demonstrated high specificity, negative predictive value, and efficiency, with over 90% for most cell classes. However, the DI-60 showed relatively lower specificity for lymphocytes (73.2%) and lower efficiency for blasts and lymphocytes (80.1% and 78.6%, respectively) compared with the MC-80. Bland-Altman analysis indicated that the absolute mean differences (%) ranged from 0.01 to 4.57 in MC-80 versus manual differential and 0.01 to 3.39 in DI-60 versus manual differential. After verification by technicians, both analyzers exhibited a very high correlation (r = 0.90-1.00) with the manual differential results in neutrophils, lymphocytes, and blasts. CONCLUSIONS: The Mindray MC-80 demonstrated good performance for leukocyte differential in PB smears, notably exhibiting higher sensitivity for blasts identification than the DI-60.

Establishing local reference intervals for full blood count and white blood cell differential counts in Cape Town, South Africa.

BACKGROUND: Accurate laboratory reference intervals (RIs) are essential to differentiate between health and disease. There are variations in haematological indices within populations relating to gender, age, ethnicity and environment. Iron deficiency is common, has a wide range of clinical morbidities and affects red cell indices. Locally derived RIs for full blood count (FBC) parameters are needed for the Western Cape region of South Africa, after the exclusion of iron deficiency. In addition, information regarding the prevalence of iron deficiency in first-time blood donors would inform blood transfusion services regarding policies to screen for and treat iron deficiency. OBJECTIVES: To establish locally derived RIs for FBC and white blood cell (WBC) differential count parameters in healthy adults in the Cape Town area, by including first-time blood donors and excluding those with iron deficiency and thalassaemic indices. These new locally established RIs could update those in use by the local National Health Laboratory Service. A secondary objective was to establish the prevalence of iron deficiency in first-time blood donors. This would inform blood donation policies regarding screening and appropriate iron supplementation in high-risk groups prior to blood donation. METHODS: This was a prospective, descriptive study with direct convenience sampling. Participants were prospective voluntary blood donors aged between 18 and 60 years, presenting for first-time blood donation. Ethnicity was self-identified. Participants who tested positive for HIV or hepatitis B and/or C viruses were excluded. Prospective participants with iron deficiency, defined by serum ferritin levels below the RI, and those with red cell indices suggestive of an underlying thalassaemia trait were excluded. FBC samples were analysed using a Sysmex XN-1000 cell counter. Statistical non-parametric methods were used to calculate the RIs, according to international guidelines. RESULTS: Of the 774 participants screened, 82 (11%) had iron deficiency and were excluded. Six hundred and sixty-two patients were included for analysis, 409 (62%) female and 253 (38%) male. The majority of the participants, 348 (53%), were between 20 and 29 years of age, with a mean age of 29 years for females and 28 years for males. Participants comprised a mix of the various ethnic groups residing in Western Cape Province. The mean haemoglobin concentration for females was lower than that for males (p<0.0001). There were significant gender differences for total WBC count, absolute neutrophil count and platelet count, with females having higher counts than males. CONCLUSIONS: Locally established, population-specific RIs are essential for the accurate interpretation of haematological indices. This study established locally derived gender-specific RIs for the Cape Town region, after exclusion of iron deficiency. These new RIs have implications for the accurate diagnoses of cytopenias, cytoses and other blood count abnormalities. Iron deficiency is common in first-time blood donors, and screening for iron deficiency using point-of-care testing should be considered.

Evaluation of microscopy, serology, circulating anodic antigen (CAA), and eosinophil counts for the follow-up of migrants with chronic schistosomiasis: a prospective cohort study.

BACKGROUND: An accurate test for the diagnosis and post-treatment follow-up of patients with schistosomiasis is needed. We assessed the performance of different laboratory parameters, including the up-converting reporter particle technology lateral flow assay to detect circulating anodic antigen (UCP-LF CAA), for the post-treatment follow-up of schistosomiasis in migrants attending a dedicated outpatient clinic in a non-endemic country. METHODS: Routine anti-Schistosoma serology results and eosinophil counts were obtained of patients with positive urine/stool microscopy and/or PCR (confirmed cases) or only positive serology (possible cases), and at least one follow-up visit at 6 (T6) or 12 (T12) months after praziquantel treatment. All sera samples were tested with the UCP-LF CAA assay. RESULTS: Forty-eight patients were included, 23 confirmed and 25 possible cases. The percentage seropositivity and median antibody titers did not change significantly during follow-up. UCP-LF CAA was positive in 86.9% of confirmed and 20% of possible cases. The percentage positivity and median CAA levels decreased significantly post-treatment, with only two patients having positive CAA levels at T12. CONCLUSIONS: The UCP-LF CAA assay proved useful for the diagnosis of active infection with Schistosoma spp. and highly valuable for post-treatment monitoring in migrants, encouraging the development of a commercial test.

Reference intervals of white blood cell parameters for healthy adults in japan.

INTRODUCTION: While white blood cell (WBC) parameters have been suggested to depend on ethnicity and gender, reference intervals in healthy Asian populations are limited. The present study established reference intervals of WBC parameters for healthy adults in Japan. METHODS: A total of 750 healthy adults (447 women and 303 men; 18-67 years old, median 40 years old) at 7 Japanese centers who participated in regular medical checkups entered this study. The WBC parameters were measured using automated hematocytometers and blood film reviews by a manual microscopic examination. RESULTS: The reference intervals of the WBC parameters according to gender in healthy adults were determined. Age-specific decreases in WBC counts of both gender groups and in neutrophil counts of women were noted. Favorable correlations between the hematocytometer and microscopic methods were found in neutrophils, lymphocytes, and eosinophils but not in monocytes or basophils. CONCLUSION: This study suggests the need to consider gender and age in the clinical use of reference intervals of WBC parameters.

Reporting Sysmex XN Absolute Neutrophil Count in Samples with Leukocyte Analyzer Flagging.

OBJECTIVE: To provide faster laboratory data reporting, we evaluated the accuracy of Sysmex XN (Sysmex Inc, Kobe, Japan) absolute neutrophil count (ANC) in the presence of analyzer flagging. METHODS: Sysmex XN and manual microscopy ANC were compared with 80 autovalidated control specimens and with 280 study specimens with analyzer flagging regarding immature granulocytes (IG) >3% or other leukocyte abnormalities. Specimens with ambiguous neutrophil clusters were excluded. RESULTS: A slight positive overall method bias was seen for Sysmex XN compared to manual microscopy (n = 280), 0.025 (95% confidence interval [CI], -0.023 to 0.069) × 109/L. With IG > 10% (n = 123) the bias was larger, but not clinically significant, 0.17 (95% CI, 0.060-0.25) × 109/L. No clinically significant difference was seen in neutropenic (ANC < 1.5 × 109/L) specimens (n = 91), 0.070 (95% CI, -0.013 to 0.14) × 109/L. CONCLUSION: These data indicate that Sysmex XN ANC can be reported in the presence of certain analyzer flagging to improve patient care.

False-positive flag of WBC and change of mean platelet volume (MPV) caused by K3-EDTA on the DxH 900 hematology analyzer.

During the evaluation of the DxH 900 hematology analyzer (Beckman Coulter, Miami, FL), we noted that some patient samples produced a false positive white blood cell (WBC) flag, neutrophil blasts (NE-blast), despite the absence of abnormal cells. We investigated whether storage time or anticoagulants such as K2- or K3-ethylenediaminetetraacetic acid (EDTA) would affect complete blood count (CBC) tests on the DxH 900. Sixty-four whole blood samples were collected in K3-EDTA tubes, and 44 were simultaneously drawn in K2-EDTA tubes. Samples were tested at the following two intervals: within 30 min of collection (0 min) and after an additional 30 min of roller-mixing at room temperature (30 min). WBC differential dataplots in 0-min K3-EDTA tubes showed a mixed cell population between lymphocytes and neutrophils in 22 patients presenting the NE-blast flag. All 22 samples revealed normal WBC differential dataplots after 30 min of roller-mixing. The significantly lower mean neutrophil volume in specimens of 0-min K3-EDTA tubes than those of 0-min K2-EDTA, 30-min K2-EDTA and 30-min K3-EDTA tubes appear to be the cause of the false flag. Unlike blood cell counts, mean platelet volume (MPV) was significantly higher at 30 min using both EDTA tubes than that at 0 min. In conclusion, K3-EDTA can produce a false positive flag, NE-blast, on the DxH 900. MPV increases over time irrespective of EDTA salt type.

The Absolute Basophil Count.

The absolute basophil count (cells/L) can be determined by manual counting of peripheral blood smears or using cell counting chambers as well as by automated hematology analyzers and fluorescence flow cytometry. Manual basophil counting of peripheral blood smears is currently regarded as the reference method, although the limitations of this method (distribution, observer, and statistical errors) are widely recognized. Automated hematology analyzers offer an advantage of larger numbers of counted cells and high throughput but are characterized by inconsistent analytical performance for basophil enumeration. Flow cytometric enumeration of circulating basophils using panels of monoclonal antibodies is being developed as novel candidate reference method for the absolute basophil count in peripheral blood. Basophil counting using fluorescence flow cytometry is characterized by high precision and statistical superiority. Emerging innovative technologies for absolute cell counts include imaging flow cytometry, mass cytometry, and on-chip blood counting, but their analytical performance for absolute basophil counts is yet to be established. Here, we describe various techniques for absolute basophil counting in peripheral blood including manual basophil counts in smears and hemocytometers and flow cytometric methodologies using double-platform, bead-based, and volumetric approaches.

A new approach for diagnosing hematological malignancies using monocytosis workflow optimization and abnormal lymphocyte/blast flag of Sysmex XN series of blood count analyzers.

INTRODUCTION: Monocytosis Workflow Optimization rule set has been developed by using mono-dysplasia-score to determine reactive monocytosis and prevent unnecessary blood smear of these patients and for detection of chronic myelomonocytic leukemia cases during complete blood count. In our study, we aimed to examine the contribution of Monocytosis Workflow Optimization rule set. METHODS: Adult patients with monocyte count ≥1.0 103 /µL and monocyte percentage ≥10% were included in our study. Blood smears were made from the samples in our laboratory. These smears were examined and patients were divided into two groups as reactive monocytosis or hematological malignancy. The groups were compared in terms of Monocytosis Workflow Optimization rule set and device flags. RESULTS: Twenty-one patients had hematological malignancies of 155 patients who were included in our study. Monocytosis Workflow Optimization rule set suggested performing blood smear in 19 of the patients with hematological malignancy, and evaluated two patients as reactive monocytosis with 90.5% sensitivity and 76.9% specificity. There was an "abnormal lymphocyte/ blast" flag in 90.5% of patients with hematological malignancies and in patients whose Monocytosis Workflow Optimization rule set defined as reactive monocytosis and it was found that sensitivity and negative predictive value reached 100%. CONCLUSION: Automated validation support systems and softwares developed especially for these systems make it possible to classify patients with their non-specific findings, as a result both contributing to the reduction of laboratory workload and costs and assisting laboratory specialists and clinicians with adding value to laboratory results.

The results of external quality assessment programme on urine leukocyte and erythrocyte counting in Poland.

INTRODUCTION: Urine particle analysis is an important diagnostic tool. The aim of this study was to evaluate the quality of urine leukocyte (WBC) and erythrocyte (RBC) counting results obtained with manual and automated methods in Polish laboratories participating in the international external quality assessment (EQA) programme. MATERIALS AND METHODS: 1400 WBC and RBC counting results were obtained from 183 laboratories in EQA surveys organised by Labquality (Helsinki, Finland) from 2017 to 2019. The between-laboratory coefficient of variation (CV), the percentage difference between the laboratories' results and target values (Q-score (%)), as well as modified Youden plots were analysed. RESULTS: For automated method groups, the medians of inter-laboratory CVs varied from 14% to 33% for WBC counting and from 10% to 39% for RBC counting. For manual method groups, the medians of CV varied from 53% to 71% (WBC) and from 55% to 70% (RBC), and they were significantly higher, in comparison to CVs for most automated method groups (P < 0.001). The highest percentage of results outside the target limits (36%) and the highest range of Q-score (%) (from - 93% to 706%) were observed for laboratories which participated in the surveys for the first or second time. The percentage of deviating results and the ranges of Q-score decreased with an increased frequency of laboratories' participation in the surveys. CONCLUSIONS: The quality of manual methods of urine WBC and RBC counting is unsatisfactory. There is an urgent need to take actions to improve laboratories' performance and to increase harmonisation of the results.

Determining hematological, biochemical and immunological reference values in healthy adults with high-risk for HIV acquisition in Mozambique.

INTRODUCTION: In many African countries, laboratory reference values are not established for the local healthy adult population. In Mozambique, reference values are known for young adults (18-24yo) but not yet established for a wider age range. Our study aimed to establish hematological, biochemical and immunological reference values for vaccine trials in Mozambican healthy adults with high-risk for HIV acquisition. METHODS: A longitudinal cohort and site development study in Mozambique between November 2013 and 2014 enrolled 505 participants between 18 to 35 years old. Samples from these healthy participants, were analyzed to determine reference values. All volunteers included in the analysis were clinically healthy and human immunodeficiency virus (HIV), hepatitis B and C virus, and syphilis negative. Median and reference ranges were calculated for the hematological, biochemical and immunological parameters. Ranges were compared with other African countries, the USA and the US National Institute of Health (NIH) Division of AIDS (DAIDS) toxicity tables. RESULTS: A total of 505 participant samples were analyzed. Of these, 419 participants were HIV, hepatitis B and C virus and syphilis negative including 203 (48.5%) females and 216 (51.5%) males, with a mean age of 21 years. In the hematological parameters, we found significant differences between sex for erythrocytes, hemoglobin, hematocrit, MCV, MCH and MCHC as well as white blood cells, neutrophils and platelets: males had higher values than females. There were also significant differences in CD4+T cell values, 803 cells/µL in men versus 926 cells/µL in women. In biochemical parameters, men presented higher values than women for the metabolic, enzymatic and renal parameters: total and direct bilirubin, ALT and creatinine. CONCLUSION: This study has established reference values for healthy adults with high-risk for HIV acquisition in Mozambique. These data are helpful in the context of future clinical research and patient care and treatment for the general adult population in the Mozambique and underline the importance of region-specific clinical reference ranges.

Effect of clinically significant thresholds of eosinophil elevation on health care resource use in asthma.

BACKGROUND: Blood eosinophil counts correlate with exacerbations, but there is a lack of consensus on a clinically relevant definition of eosinophil count elevation. OBJECTIVE: To analyze health care resource use among patients with elevated blood eosinophil counts defined at 150 cells/µL or greater and 300 cells/µL or greater. METHODS: Data on patients who received a diagnosis of asthma between 2007 and 2016 were extracted from EMRClaims + database. Patients were defined as having elevated eosinophil counts if any test result during 3 months before follow-up found blood eosinophil count of 150 cells/µL or more or 300 cells/µL or more. Hospitalizations, emergency department visits, outpatient visits, and associated costs were compared. With logistic regression, likelihood of hospitalization was assessed in the presence of eosinophil elevation. RESULTS: Among 3687 patients who met the study criteria, 1152 received a test within 3 months before the follow-up period, of whom 644 (56%) had elevated eosinophil counts of 150 cells/µL or greater and 322 (29%) had eosinophil counts of 300 cells/µL or greater. Overall, the mean (SD) number of hospitalizations for patients with elevated eosinophil counts vs the comparator was significantly greater (0.29 [0.92] vs 0.17 [0.57], P < .001 at ≥150 cells/µL and 0.30 [0.95] vs 0.18 [0.61] at ≥300 cells/µL, P = .001). The total mean cost was significantly greater for patients with elevated eosinophil counts (at ≥150 cells/µL: $10,262 vs $7149, P < .001 and at ≥300 cells/µL: $9966 vs $7468, P = .003). CONCLUSION: Patients with asthma incurred greater health care resource use when their blood eosinophil counts were elevated at 150 cells/µL or greater and 300 cells/µL or greater as measured within 3 months of follow-up.

[Mastering the analytical process of the Complete Blood Count: how and why?] / Maîtrise du processus analytique de la Numération Formule Sanguine : comment et pourquoi ?

This is a prospective study realized at the level of the hematology department and blood transfusion center of the University Hospital Center (CHU) of Dr Ben Badis of Constantine and spread out over a period of one year (from January 1st to December 31st). The work focused on the analytical processes mastery of the NFS needs a compulsory step concerning technical and organizational laboratory skills respecting the ISO 15189 laws going through a mastery of support processes (humain resourses, informatics, materials, documents, management) indispensable for the good function of analytic proceedings, a performance evaluation of the hematology analyzer Advia (2120 I and II and 560) and quality control management (intern, extern). The analytic performance evaluation of Advia gives reliable results reproductible and stable for use of the routine automatisation good inter-machine correlation and laboratory performance in terms of the quality extern evaluation with military hospital laboratory.

False-positive of blood culture instrument: leukocytosis, overfilled vials or defective position?

Continuous monitoring of the performances of blood culture instrument can be based on the indicators proposed by the QUAMIC. Of these, the analytic performance indicator evaluates the rate of false-positive vials. False-positives vials can be reported by the device in case of leukocytosis or when vials are overfilled. In our laboratory, we record prospectively in our software all false positive vials as well as the position used for their incubation. These data are analyzed at least twice a year. For the first half of 2016, this strategy allowed us to identify a defective position. We then evaluated the impact of this anomaly as very weak. The one-year follow-up after the position repair confirmed a correction of the problem. Thus, traceability of positions reporting unexplained false-positive vials (i.e. neither due to leukocytosis nor overfilled vials) can allow laboratories to identify a defective position. This survey, if done prospectively, is simple to perform and not time-consuming. It could usefully complement the analytical performance indicator based on the false-positive rate.

Can the 72-hour rule based on "Blast/Abn Lymph" flag on Sysmex XN-10 optimize the workflow in hematology laboratory?

Despite the continuing improvement of automated blood cell counters, confirmation by blood smear examination remains the gold standard in case of anomalies. With a constant goal of standardisation, different experts committees (e.g. the French-speaking cellular hematology group (Groupe francophone d'hématologie cellulaire, GFHC and the ISLH International society for laboratory hematology) recently published criteria for microscopic analysis of blood smears. Cornet et al. evaluated the application of those criteria and propose to suppress any review for 72 hours when a "Blast/Abn lymph" flag is triggered for a sample with no abnormal cell on the microscopic review. The aims of our study were to retrospectively evaluate whether this 72-hour rule adequately operates and whether it is possible to extend the arbitrary 72-hour timeframe to 96h and 144h. To achieve this goal, 40,688 blood samples were collected from three French-speaking hospitals. 1,548 samples presented an isolated "Blast/Abn lymph" flag. Only 221 samples presented the application of the 72-hour rule at least once for our study period. We were able to extend this rule to 144 hours for 10 samples of them. All blood smears for which the rule was applied were verified and there was no abnormal cell on smears at 72 and 144 hours. In conclusion, the 72-hour rule derived from the GFHC's criteria is secure and reduces the slide review rate and thus the production costs and the turnaround time of hemogram results. Further investigations could confirm that its extension to 144 hours is also adequate.

Full blood count and white cell differential count reference ranges obtained from a healthy urban South African population residing in the Western Cape of South Africa.

BACKGROUND: Research has suggested that individuals of African descent have lower white cell and neutrophil counts than Caucasians. These differences could lead to incorrect clinical decisions, and therefore, ethnic-specific reference ranges are required. The Western Cape region of South Africa is uniquely diverse, comprising Caucasian, Mixed Ancestry and those of African descent. The aim of this study was to compare the full blood count and differential counts across the three major ethnic groups residing in this area and to propose appropriate RIs. METHODS: The study formed part of the international project led by the Committee on Reference Intervals and Decision Limits (C-RIDL), and therefore, the strict guidelines laid out by the committee were followed. Full blood count and differential counts were performed on a Beckman Coulter ACT 5 diff AL analyser within 2-4 hours of collection and were reported as mean (standard deviation), 2.5th and 97.5th percentiles. Comparisons were analysed using Spss v25 and Statistica v13, and a P value of < 0.05 was considered significant. RESULTS: Reference ranges for Caucasian and Mixed Ancestry individuals were similar while white cell (P = 0.016), monocyte (P < 0.001), neutrophil (P = 0.034) and red cell indices were significantly different amongst the three population groups. There were however no statistical and clinical significant differences between the eosinophil, lymphocyte, red cell and platelet counts across the three groups. CONCLUSION: In conclusion, subjects of Mixed Ancestry, in this region, have similar reference intervals to those of European descent, while lower white cell and neutrophil counts in Africans have been confirmed.