Lack of harmonization in high fluorescent cell automated counts with body fluids mode in ascitic, pleural, synovial, and cerebrospinal fluids.

INTRODUCTION: Cellular analysis in body fluids (BFs) provides important diagnostic information in various pathological settings. This study was hence aimed at comparing automated cell count obtained with Mindray BC-6800 (BC-BF) vs Sysmex XN-series (XN-BF) and evaluating other quantitative and qualitative information provided by these analyzers in ascitic (AF), pleural (PF), synovial (SF), and cerebrospinal (CSF) fluids. METHODS: Three hundred and fifty-one samples (99 AFs, 45 PFs, 75 SFs, and 132 CSFs) were analyzed in parallel with BC-BF, XN-BF, and optical microscopy (OM). The study also included the assessment of diagnostic agreement among BC-BF, XN-BF, and OM. RESULTS: The comparison of BC-BF vs XN-BF yielded slopes of Passing and Bablok regression always comprised between 0.9 and 1.0 except for EO-BF and HF-BF, whilst the intercepts ranged from -0.4 for MN-BF and 12.0 for PMN-BF. The bias was comprised between -103.3% and 67.1% for HF-BF and EO-BF, respectively. A significant bias was found for TC-BF, WBC-BF, HF-BF (negative bias) and for PMN-BF and EO-BF (positive bias). The agreement (Cohen's kappa) between XN-BF and BC-BF was always ≥0.7, ranging between 0.87 in CSFs and 0.94 in AFs, and that with OM was similar (ie, 0.85 and 0.96). CONCLUSION: The cytometric analysis of BF samples using BC-BF and XN-BF is clinically favorable when appropriately combined with OM. Quantitative and qualitative parameters displayed optimal agreement, whilst instrument-specific cut-offs should be defined and implemented for HF-BF and EO-BF. Further efforts should be made for achieving better harmonization in cytometric analysis of BF samples.

Short- and medium-term biological variation estimates of red blood cell and reticulocyte parameters in healthy subjects.

BACKGROUND: The integrated evaluation of traditional and innovative red blood cell (RBC) and reticulocyte parameters is a rapid, inexpensive and non-invasive diagnostic tools for differential diagnosis and follow-up of anemia and other pathological conditions needing bone marrow erythropoiesis assessment. Therefore, estimating the biological variation (BV) of these parameters is essential for evaluating the analytical performance of hematological analyzers, and for enabling accurate data interpretation and appropriate clinical management. This study aims to define short- and medium-term BV estimates and reference change value (RCV) of RBC and reticulocyte parameters. METHODS: Twenty-one healthy volunteers participated in the assessment of medium-term BV (blood sampling once/week, five consecutive weeks) and 22 volunteers in the assessment of short-term BV (blood sampling once/day, five consecutive days) using Sysmex XN. Outlier analysis was performed before CV-ANOVA, to determine BV estimates with confidence intervals (CI). RESULTS: Medium- and short-term within-subject BV were between 0.3% and 16.4% and 0.2%-10.4% (MCH and IRF), respectively, whereas medium and short-term between-subjects BV ranged between 0.9% and 66.6% (MCHC and Micro-R) and 1.4%-43.6% (MCHC and IRF), respectively. The RCVs were similar for all parameters in both arms of the study, except for hemoglobin, RDW-CV and MCV. CONCLUSIONS: This study allowed for estimating the BV of many RBC and reticulocyte parameters, some of which have not been currently explored. For RBC, hemoglobin, RDW-CV and MCV it seems advisable to use RCV calculated according to monitoring time and/or differentiated by sex. As regards analytical goals, we suggest using the most stringent targets found in the short-term arm of this study.

Innovative haematological parameters for early diagnosis of sepsis in adult patients admitted in intensive care unit.

AIMS: This study was aimed to investigate the role of erythrocyte, platelet and reticulocyte (RET) parameters, measured by new haematological analyser Sysmex XN and C reactive protein (CRP), for early diagnosis of sepsis during intensive care unit (ICU) stay. METHODS: The study population consisted of 62 ICU patients, 21 of whom developed sepsis during ICU stay and 41 who did not. The performance for early diagnosing of sepsis was calculated as area under the curve (AUC) of receiver operating characteristics curves analysis. RESULTS: Compared with CRP (AUC 0.81), immature platelet fraction (IPF) (AUC 0.82) showed comparable efficiency for identifying the onset of sepsis. The association with the risk of developing sepsis during ICU stay was also assessed. One day before the onset of sepsis, a decreased of RET% was significantly associated with the risk of developing sepsis (OR=0.35, 95% CI 0.14 to 0.87), whereas an increased of IPF absolute value (IPF#) was significantly associated with the risk of developing sepsis (OR=1.13, 95% CI 1.03 to 1.24) 2 days before the onset of sepsis. The value of CRP was not predictive of sepsis at either time points. CONCLUSIONS: IPF# and RET% may provide valuable clinical information for predicting the risk of developing sepsis, thus allowing early management of patients before the onset of clinically evident systemic infections.

Preliminary evaluation of UF-5000 Body Fluid Mode for automated cerebrospinal fluid cell counting.

BACKGROUND: Cellular analysis of cerebrospinal fluid (CSF) provides important diagnostic information in various medical conditions. The aim of this study was to evaluate the application of Sysmex UF-5000 body fluid mode in cytometric analysis of CSF compared to Light Microscopic (LM). METHODS: Eighty-one consecutive CSF samples were analyzed by UF-5000 body fluid mode and by LM. The study also included the evaluation of: limit of Blank (LoB), limit of Detection (LoD), limit of Quantitation (LoQ), carryover and linearity. RESULTS: For total nucleated cells (TNC-UF) and white blood cells (WBC-UF) LoB, LoD and LoQ were 1×106cells/L, 1.8×106cells/L and 1.9×106cells/L respectively. For red blood cells (RBC) LoB was 2×106cells/L, LoD was 3.5×106cells/L and LoQ was 14×106cells/L respectively. Linearity was excellent, carryover was negligible. The agreement between UF-5000 body fluid mode parameters and manual cell counts was good in all CSF samples with bias ranged between -0.5 and 25.1×106cells/L. The ROC curve analysis showed an area under curve of 0.99 for both TNC-UF and WBC-UF parameters. CONCLUSIONS: The UF-5000 body fluid mode offers rapid and accurate counts in clinically relevant concentration ranges, replacing the LM for most samples. However, in samples with abnormal cell counts or with abnormal scattergram the need for microscopic review remains.

Clinical significance of cell population data (CPD) on Sysmex XN-9000 in septic patients with our without liver impairment.

BACKGROUND: This study evaluated the clinical significance of cell population data (CPD) parameters obtained on Sysmex XN-9000 in septic patients admitted to intensive care unit (ICU) and stratified according to liver function. METHODS: The study population consisted in 84 patients, 44 of whom did not develop sepsis (NS), whereas the remaining 40 developed sepsis (SE) (n=24) or septic shock (SS) (n=16). Two hundred ostensibly healthy blood donors [healthy subjects (HS)], undergoing routine blood testing before a regular blood donation, were studied. RESULTS: Except for neutrophils and lymphocytes cell size (NE-FCS and LY-Z), all other CPD values were significantly different in ICU patients compared to HS. Neutrophils and monocytes fluorescence intensity (NE-SFL and MO-X) values were significantly higher in SS compared to sepsis and not develop sepsis patients. The value of many parameters was also different according to liver function. Overall, MO-X and neutrophils fluorescence intensity (NE-SFL) exhibited the best performance for diagnosing sepsis in all patients (AUC, 0.75 and 0.72), as well as in those with (AUC, 0.95 and 0.89) or without (AUC, 0.72 for both) liver impairment. These parameters were also significantly correlated with Sequential Organ Failure Assessment (SOFA) score. CONCLUSIONS: This study suggested that some novel CPD parameters (namely NE-SFL and MO-X) may provide useful information for diagnosis and management of sepsis.

Assessment of blood sample stability for complete blood count using the Sysmex XN-9000 and Mindray BC-6800 analyzers.

BACKGROUND: Different hematological analyzers have different analytical performances that are often reflected in the criteria for sample stability of the complete blood count. This study aimed to assess the stability of several hematological parameters using the XN-9000 Sysmex and BC-6800 Mindray analyzers. METHODS: The impact of storage at room temperature and 4°C was evaluated after 2, 4, 6, 8, 24, 36 and 48h using ten normal and 40 abnormal blood samples. The variation from the baseline measurement was evaluated by the Steel-Dwass-Critchlow-Fligner test and by Bland-Altman plots, using quality specifications and critical difference as the total allowable variation. RESULTS: Red blood cells and reticulocyte parameters (i.e. hematocrit, mean corpuscular volume, mean corpuscular hemoglobin concentration, red blood cell distribution width, immature reticulocyte fractions, low-fluorescence reticulocytes, middle-fluorescence reticulocytes, high fluorescence mononuclear cells) showed less stability compared to leukocyte and platelet parameters (except for monocyte count and mean platelet volume). The bias for hematocrit, mean corpuscular volume, mean corpuscular hemoglobin concentration and red blood cell distribution width coefficient of variation was higher than the critical difference after 8h using both analyzers. CONCLUSION: Blood samples measured with both analyzers do not show analytically significant changes in up to 2h of storage at room temperature and 4°C. However, the maximum time for analysis can be extended for up to 8h when the bias is compared to the critical difference.

Erythroblastaemia in natalizumab-treated patients with multiple sclerosis.

BACKGROUND: Natalizumab is a monoclonal antibody that significantly reduces the occurrence of relapses in relapse-remitting multiple sclerosis (RRMS) patients. Early papers on the clinical use of natalizumab in RRMS patients reported erythroblastemia as occasional and transient. OBJECTIVES: to determine the prevalence and absolute count of erythroblasts (nucleated red blood cells, NRBCs) in peripheral blood of RRMS patients in different treatment groups and healthy controls from the same geographic area using the same equipment for laboratory analysis. METHODS: We retrospectively evaluated the samples of 203 consecutive RRMS patients including 26 subjects on natalizumab, 17 on fingolimod, 72 on interferon, 41 on glatiramer acetate, 47 treatment-naïve and 240 healthy controls from the same geographic area. Blood samples were processed using an XN-9000-Hematology Analyzer and subsequent microscopic verification. In the natalizumab-treated patients we performed an additional analysis in order to detect the expression of CD34+ cells in peripheral blood, as confirmation of a bone marrow mobilization. RESULTS: The prevalence of patients with NRBCs positivity was significantly higher in natalizumab-treated patients (92%) compared with the other treatment groups and healthy controls (0%) (p<0.0005). The median absolute NRBCs count was significantly higher in natalizumab-treated patients (median 0.020, p<0.0005) than in the other treatment groups and healthy controls. Natalizumab-treated patients also had higher levels of white blood cells than all other groups and lower haemoglobin levels than healthy subjects (p<0.01), but no morphologic alterations were evident at a subsequent review of red blood cells, platelets and white blood cells. CD34+ cells levels were consistent with mobilization of haematopoietic stem cells from the bone marrow (median 8 cells/µL, IQR 5-12). CONCLUSIONS: We confirm erythroblastaemia as a frequent finding of natalizumab treatment in RRMS patients. More extended knowledge and adequate long-term observation of this phenomenon are essential to better understand any pathological implication.

Cell Population Data and reflex testing rules of cell analysis in pleural and ascitic fluids using body fluid mode on Sysmex XN-9000.

BACKGROUND: Although optical microscopy (OM) remains the reference technique for analysis of ascitic (AF) and pleural (PF) fluids, novel hematological analyzers are equipped with modules for body fluid (BF) analysis. This study was aimed to analyze the performance of XN-BF module in Sysmex XN-9000, and to develop validation rules for automated cell counts in BFs. METHODS: The evaluation of XN-BF module included assessment of carryover, Limit of Blank (LoB), Limit of Detection (LoD), Limit of Quantitation (LoQ), linearity, data comparison with OM, and development of rules for assisting the validation of automated analysis of BFs and activating reflex testing. RESULTS: The carryover was negligible. The LoB, LoD, LoQ and linearity were always excellent. The comparison with OM was characterized by Pearson's correlations ranging from r=0.50 to r=0.99 (p<0.001), modest bias and high diagnostic concordance (Area Under the Curve between 0.85 and 0.99). The use of instrument-specific cut-offs further increased diagnostic concordance. The implementation of reflex testing rules based on XN-BF data increased sensitivity and specificity of BFs classification to 0.98 and 0.95. CONCLUSIONS: Our results suggest that the XN-BF module on Sysmex-9000 may be a suitable alternative to OM for screening BF samples, especially when specific validation rules are used.

Reflex Testing Rules for Cell Count and Differentiation of Nucleated Elements in Pleural and Ascitic Fluids on Sysmex XE-5000.

Flow cytometry is widely used in many laboratories for automated nucleated cell counts and their differentiation in body fluids. The implementation of new reflex testing rules on these automated instruments could open new frontiers in laboratory workflow, improving characterization of body fluids and clinical diagnosis and decreasing costs. Ascitic (150) and pleural (33) fluids were collected and assessed by XE-5000 and optical microscopy. Cell counts performed with the methods showed a Pearson's correlation of 0.98 (p < 0.0001), Passing-Bablok regression y = 0.99x + 2.44, and bias of 32.3. In ascitic fluids, the best diagnostic performance was found for polymorphonuclear and neutrophil counts on XE-5000, which exhibited areas under the curve (AUCs) 0.98 (p < 0.0001) and 0.99 (p < 0.0001), respectively. In pleural fluids the best diagnostic performance was found for polymorphonuclear percent parameter, which displayed 0.97 (p < 0.0001). Specific reflex test rules based on these parameters were characterized by 92% diagnostic concordance, 1.00 sensitivity, and 0.84 specificity with optical microscopy. The application of a set of reflex testing rules may improve the diagnostic performance of XE-5000, increasing its reliability for routine automated cell count in body fluids. We acknowledge that further studies should be planned to validate our findings according to clinical data.

Assessment of blood sample stability for complete blood count using the Sysmex XN-9000 and Mindray BC-6800 analyzers

Background: Different hematological analyzers have different analytical performances that are often reflected in the criteria for sample stability of the complete blood count. This study aimed to assess the stability of several hematological parameters using the XN-9000 Sysmex and BC-6800 Mindray analyzers. Methods: The impact of storage at room temperature and 4 ◦C was evaluated after 2, 4, 6, 8, 24, 36 and 48h using ten normal and 40 abnormal blood samples. The variation from the baseline measurement was evaluated by the Steel­Dwass­Critchlow­Fligner test and by Bland­Altman plots, using quality specifications and critical difference as the total allowable variation. Results: Red blood cells and reticulocyte parameters (i.e. hematocrit, mean corpuscular volume, mean corpuscular hemoglobin concentration, red blood cell distribution width, immature reticulocyte fractions, low-fluorescence reticulocytes, middle-fluorescence reticulocytes, high fluorescence mononuclear cells) showed less stability compared to leukocyte and platelet parameters (except for monocyte count and mean platelet volume). The bias for hematocrit, mean corpuscular volume, mean corpuscular hemoglobin concentration and red blood cell distribution width coefficient of variation was higher than the critical difference after 8h using both analyzers. Conclusion: Blood samples measured with both analyzers do not show analytically signifi- cant changes in up to 2h of storage at room temperature and 4 ◦C. However, the maximum time for analysis can be extended for up to 8h when the bias is compared to the critical difference

Analytical evaluation of Sysmex UF-1000i for flow cytometric analysis of peritoneal fluid.

OBJECTIVE: To evaluate analytical performance of Sysmex UF-1000i for peritoneal fluid analysis. METHODS: Functional sensitivity, imprecision, linearity and comparison studies were performed on peritoneal fluids. RESULTS: Total imprecision was 1.6-4.7%, functional sensitivity 27/µL for white blood cell (WBC) and 32/µL for total nucleated cell (TNC) count. Linearity was excellent up to 983 cell/µL, carry-over <0.2%, correlation with manual microscopy always greater than 0.992. CONCLUSION: The instrument exhibited optimal performance at the conventional WBC diagnostic thresholds.