Two cases with discrepancy in the quantitative cytological assessment of cerebrospinal fluid in neonatal samples using light microscopy in comparison with Sysmex XN-1000

We present two cases from the neonatal department with cerebrospinal fluid examination. We revealed a striking discrepancy in polymorphonuclear (PMN) and mononuclear (MN) cell counts using conventional light microscopy in comparison with automated analyzer Sysmex XN-1000 (PMNs - 13 vs. 173x106/L, MNs - 200 vs. 67x106/L in case 1 and PMNs - 13 vs. 372x106/L, MNs - 411 vs. 179x106/L in case 2). We revealed the dominant presence of hemosiderophages in both cases in cytospin slide. Even though Sysmex XN-1000 offers fast examination with a low sample volume, there is possibility of misdiagnosis, with negative impact on the patient.

Accuracy of automated analyzers for the estimation of CSF cell counts: A systematic review and meta-analysis

This systematic review evaluates the evidence for accuracy of automated analyzers that estimate cerebrospinal fluid (CSF) white blood cell counts (WBC) compared to manual microscopy. Inclusion criteria of original research articles included human subjects, English language, and manual microscopy comparator. PUBMED, EMBASE and Cochrane Review databases were searched through 2019 and QUADAS-2 Tool was used for assessment of bias. Data were pooled and analyzed by comparison method, using random effects estimation. Among 652 titles, 554 abstracts screened, 104 full-text review, 111 comparisons from 41 studies were included. Pooled estimates of sensitivity and specificity (n = 7) were 95% (95%-CI 93%-97%) and 84% (95%-CI: 64%-96%), respectively. Pooled R2 estimates (n = 29) were 0.95 (95%-CI: 0.95-0.96); Pooled spearman rho correlation (n = 27) estimates were 0.95 (95% CI 0.95-0.96). Among those comparisons using Bland-Altman analysis (n = 11) pooled mean difference was estimated at 0.98 (95% CI-0.54-2.5). Among comparisons using Passing-Bablok regressions (n = 14) the pooled slope was estimated to be 1.05 (95% CI 1.03-1.07). Q tests of homogeneity were all significant with the exception of the Bland-Altman comparisons (I2 10%, p value 0.35). There is good overall accuracy for CSF WBC by automated hematologic analyzers. These findings are limited by the small sample sizes and inconsistent validation methodology in the reviewed studies.

Comparison of Sysmex XN-V body fluid mode and deep-learning-based quantification with manual techniques for total nucleated cell count and differential count for equine bronchoalveolar lavage samples

BACKGROUND

Bronchoalveolar lavage (BAL) is a diagnostic method for the assessment of the lower respiratory airway health status in horses. Differential cell count and sometimes also total nucleated cell count (TNCC) are routinely measured by time-consuming manual methods, while faster automated methods exist. The aims of this study were to compare: 1) the Sysmex XN-V body fluid (BF) mode with the manual techniques for TNCC and two-part differential into mononuclear and polymorphonuclear cells; 2) the Olympus VS200 slide scanner and software generated deep-learning-based algorithm with manual techniques for four-part differential cell count into alveolar macrophages, lymphocytes, neutrophils, and mast cells. The methods were compared in 69 clinical BAL samples.

RESULTS

Incorrect gating by the Sysmex BF mode was observed on many scattergrams, therefore all samples were reanalyzed with manually set gates. For the TNCC, a proportional and systematic bias with a correlation of r = 0.79 was seen when comparing the Sysmex BF mode with manual methods. For the two-part differential count, a mild constant and proportional bias and a very small mean difference with moderate limits of agreement with a correlation of r = 0.84 and 0.83 were seen when comparing the Sysmex BF mode with manual methods. The Sysmex BF mode classified significantly more samples as abnormal based on the TNCC and the two-part differential compared to the manual method. When comparing the Olympus VS200 deep-learning-based algorithm with manual methods for the four-part differential cell count, a very small bias in the regression analysis and a very small mean difference in the difference plot, as well as a correlation of r = 0.85 to 0.92 were observed for all four cell categories. The Olympus VS200 deep-learning-based algorithm also showed better precision than manual methods for the four-part differential cell count, especially with an increasing number of analyzed cells.

CONCLUSIONS

The Sysmex XN-V BF mode can be used for TNCC and two-part differential count measurements after reanalyzing the samples with manually set gates. The Olympus VS200 deep-learning-based algorithm correlates well with the manual methods, while showing better precision and can be used for a four-part differential cell count.

Development and evaluation of automated synovial fluid total cell count on an Iris iQ® 200 for identifying patients at risk of septic arthritis

Septic arthritis is a diagnostic emergency. The white blood cell (WBC) count, in synovial fluid (SF), can guide the diagnosis. From November 2021 to November 2022, we included 350 SF. The WBC count was performed with the Iris iQ® 200 compared with the manual method. Automated and manual counts displayed good correlation. However, a Bland Altman plot demonstrates a higher percentage difference at higher WBC counts. The use of Iris iQ® 200 for SF analysis enables a rapid and accurate assessment for WBC count. Its implementation would advantageously replace the long and tedious optical analysis in daily routine.

Automated and manual microscopic analyses for leukocyte differential counts in exudative pleural effusions: Real-world disagreement and clinical application

Differential leukocyte counts of pleural fluid are routinely recommended for the early diagnosis and management of exudative pleural effusions. Rapid automated cellular analysis agrees strongly with standard manual microscopic counts and has become a reality in many clinical laboratories. However, discordant results sometimes observed between automated and manual analyses raise concern about using automated analysis to aid prompt differential diagnosis. This study aimed to evaluate the real-world disagreement between automated and manual leukocyte analyses in exudative pleural effusions and to investigate whether the discordant results occur in specific cellular ranges or randomly. We conducted a retrospective study of patients who were diagnosed with parapneumonic pleural effusions (PPE), tuberculous pleural effusions (TPE), and malignant pleural effusions (MPE) between September 2018 and December 2020. Differential and predominant leukocyte counts were performed using an automated XN-350 analyzer with a two-part differential count consisting of polymorphonuclear (PMN) and mononuclear (MN) leukocytes and a manual method with Wright-stained cytospin slides. We compared the two methods on cases of 109 PPEs, 50 TPEs, and 116 MPEs. Although the overall correlation between the two methods for differential leukocyte counts was excellent, there were etiologic variations; MPEs showed a lower correlation compared to PPEs and TPEs. Automated-PMN predominance almost corresponded to manual cytospin-neutrophilic predominance. In contrast, ~10% of the automated-MN predominance did not correspond with the cytospin-lymphocytic predominance. These discrepancies occurred most in the automated-MN% range of 51% to 60%, followed by 61% to 70%. The PMN% range ≥50% and <30% on the automated analysis reliably corresponds to the neutrophilic and lymphocytic predominance, respectively. However, the MN% range of 51% to 70% may not coincide with lymphocytic predominance on manual cytospin analysis. This range leaves the potential cause of exudative pleural effusions open.

Performance evaluation of automated cell counts compared with reference methods for body fluid analysis

OBJECTIVES

Cellular analysis of body fluids (BFs) can assist clinicians for the diagnosis of many medical conditions. The aim of this work is the evaluation of the analytical performance of the UF-5000 body fluid mode (UF-BF) analyzer compared to the gold standard method (optical microscopy, OM) and to XN-1000 (XN-BF), another analyzer produced by the same manufacturer (Sysmex) and with a similar technology for BF analysis.

METHODS

One hundred BF samples collected in K₃EDTA tubes were analyzed by UF-BF, XN-BF and OM. The agreement was evaluated using Passing and Bablok regression and Bland-Altman plot analysis. The receiver operating characteristic (ROC) curves were selected for evaluating the diagnostic agreement between OM classification and UF-BF parameters.

RESULTS

Comparison between UF-BF and OM, in all BF types, showed Passing and Bablok's slope comprised between 0.99 (polymorphonuclear cells count, PMN-BF) and 1.39 (mononuclear cells count, MN-BF), the intercepts ranged between 26.47 (PMN-BF parameter) and 226.80 (white blood cell count). Bland-Altman bias was comprised between 7.3% (total cell count, TC-BF) and 52.9% (MN-BF). Comparison between UF-BF and XN-BF in all BF showed slopes ranged between 1.07 (TC-BF and PMN-BF) and 1.16 (MN-BF), intercepts ranged between 8.30 (PMN) and 64.78 (WBC-BF). Bland-Altman bias ranged between 5.8 (TC-BF) and 21.1% (MN-BF). The ROC curve analysis showed an area under the curve ranged between 0.9664 and 1.000.

CONCLUSIONS

UF-BF shows very good performance for the differential counts of cells in ascitic, pleural and synovial fluids and therefore it is useful to screen and count cells in this type of BF.

A sample-preparation-free, automated, sample-to-answer system for cell counting in human body fluids

While many clinical laboratory tests are now highly automated, body fluid cell counting, particularly in low-cellularity samples such as cerebral spinal fluid (CSF), is often performed manually. Here, we report a simple, cost-effective method to obtain white and red blood cell counts from human body fluids such as CSF. The method consists of a compact, automated, and low-cost fluorescence microscope system, coupled to a sample chamber containing all of the necessary reagents in dry form to stain and prepare the sample. Sample focus and scanning are handled automatically, and the acquired multimodal images are automatically analyzed to extract cell counts. Comparison with manual counting on over 200 clinical samples shows excellent agreement. As the system counts a substantially larger image region than a standard manual cell count, we find our sensitivity to extremely low cellularity samples to potentially be higher than the manual gold standard, evidenced by our system recording images of cells in samples whose cell count was registered as "0" by a trained user. Thus, our system holds promise for routine, automated, and sensitive analysis of body fluids whose cellularity extends across a wide dynamic range.

Automated Analysis of Cerebrospinal Fluid Cells Using Commercially Available Blood Cell Analysis Devices-A Critical Appraisal

The analysis of cells in the cerebrospinal fluid (CSF) is a routine procedure that is usually performed manually using the Fuchs–Rosenthal chamber and cell microscopy for cell counting and differentiation. In order to reduce the requirement for manual assessment, automated analyses by devices mainly used for blood cell analysis have been also used for CSF samples. Here, we summarize the current state of investigations using these automated devices and critically review their limitations. Despite technical improvements, the lower limit for reliable leukocyte counts in the CSF is still at approximately 20 cells/µL, to be validated depending on the device. Since the critical range for clinical decisions is in the range of 5–30 cells/µL this implies that cell numbers < 30/µL require a manual confirmation. Moreover, the lower limit of reliable erythrocyte detection by automated devices is at approximately 1000/µL. However, even low erythrocyte numbers may be of clinical importance. In contrast, heavily hemorrhagic samples from neurosurgery may be counted automatically at an acceptable precision more quickly. Finally, cell differentiation by automated devices provides only a rough orientation for lymphocytes, granulocytes and monocytes. Other diagnostically important cell types such as tumor cells, siderophages, blasts and others are not reliably detected. Thus, although the automation may give a gross estimate sufficient for the emergency room situation, each CSF requires a manual microscopy for cytological evaluation for the final report. In conclusion, although automated analysis of CSF cells may provide a first orientation of the cell profile in an individual sample, an additional manual cell count and a microscopic cytology are still required and represent the gold standard.

A comparison of the analysis of 3 types of body fluids using the XN-350 hematology analyzer versus light microscopy assessment

We evaluated the capacity of the XN-350 instrument to analyze 3 different types of body fluid samples under "body fluid mode."The performance of XN-350 was evaluated in terms of precision, carryover, limit of blank, limit of detection, limit of quantification, and linearity. Cell enumeration and differential data produced by the XN-350 were compared to manual chamber counting results in 63 cerebrospinal fluid (CSF), 51 ascitic fluid, and 51 pleural fluid (PF) samples. Comparisons between XN-350 versus Cytospin data were also performed in PF samples.The precision, carry-over, limit of blank, and linearity of the XN-350 were acceptable. The limits of detection for white blood cells (WBCs) and red blood cells were 1.0/μL, and 1,000.0/μL, respectively; the corresponding limits of quantitation (LOQs) were 5.0/μL and 2,000.0/μL, respectively. The XN-350's cell enumeration and differential counting correlated well with those of manual chamber counting for all 3 sample types (except for differential counting in CSF samples), particularly parameters involving monocytes (r = 0.33) and mononuclear cells (MO- body fluid [BF]; r = 0.26), as well as total cell (TC-BF) enumeration (r = 0.50) and WBC-BF (r = 0.50) in PF samples. The MO-BF in CSF samples differed significantly from manual chamber counting results, but neither TC-BF nor WBC-BF in PF samples did. The XN-350 also showed good correlations with Cytospin analyses for differential counting of neutrophils, lymphocytes, and monocytes in PF samples. The differential counting of eosinophils via the XN-350 and Cytospin were not significantly correlated, but the difference between them was not significant.The XN-350 is an acceptable alternative to manual fluid analysis. Samples with low cellularity around the LOQ should be checked manually. Moreover, manual differential counting should be performed on CSF samples, particularity those with low cell numbers.

Cytological examination of cerebrospinal fluid: Sysmex UF-1000i versus optical microscopy

We evaluated the body fluid module on Sysmex UF-1000i (UF-1000i-BF) for analysis of white blood cell (WBC) and red blood cell (RBC) in cerebrospinal fluid. We collected 93 cerebrospinal fluid samples and compared the results of the UF-1000i-BF mode with the Fast-Read 102 disposable counting cell. Results shows a good correlation between the UF-1000i and the microscopic examination. The concordance percentage is 99.06% for white blood cells and 85.18% for red blood cells. The UF-1000i-BF mode offers rapid and reliable total WBC and RBC counts for initial screening of cerebrospinal fluid, and can improve the workflow in a routine laboratory.

Multicenter performance evaluation of the Abbott Alinity hq hematology analyzer

Background

Alinity hq (Abbott) is a new high-throughput hematology analyzer that exclusively employs optical principles for detecting and enumerating blood cells. It reports 29 parameters, including a six-part white blood cell (WBC) differential. The aim of this multicenter study was to evaluate the analytical and clinical performance of the Alinity hq.

Methods

Complete blood count (CBC) results and morphological flagging were compared to that of CELL-DYN Sapphire (Abbott) and 2 × 200-cell manual differential results, on 1473 whole-blood samples from a well-defined patient population from three different clinical laboratories in the Netherlands. In addition, within-run and within-laboratory precision, linearity, limit of quantitation, carryover and sample stability were assessed. External quality assessment samples were also evaluated.

Results

Data analysis demonstrated strong concordance of Alinity hq results with those of CELL-DYN Sapphire for all CBC parameters, except for basophil granulocytes. Alinity hq WBC differential showed high level of agreement with manual differential results and exhibited a better agreement with manual basophil results than CELL-DYN Sapphire. The sensitivity of the Alinity hq Blast flag was 57.6%, equal to the 57.6% sensitivity of the CELL-DYN Sapphire’s Blast Alert. When considering samples with ≥5% blasts, the sensitivity of the Alinity hq Blast flag was 70.0%. Analytical performance of Alinity hq was shown to be consistent with state-of-the-art (SOTA) performance characteristics.

Conclusions

Alinity hq CBC measurands demonstrated good overall agreement with results obtained with CELL-DYN Sapphire, as well as manual WBC differential. The analytical and clinical performance characteristics of Alinity hq make it well suited for clinical laboratories.

Effect of sample processing and time delay on cell count and chemistry tests in cerebrospinal fluid collected from drainage systems

Introduction

Cerebrospinal fluid (CSF) from extra-ventricular drainage (EVD) systems is routinely analysed to diagnose EVD–related bacterial meningitis. We investigated the effect of time delay and sample processing on cell count and basic biochemistry results in EVD CSF to define optimal turnaround time and whether manual and automated cell counting are comparable in such samples.

Materials and methods

In total, 32 EVD CSF samples were analysed. Baseline testing included cell counting (Fuchs-Rosenthal chamber and Sysmex XE5000) and biochemistry analyses (glucose, lactate, proteins). Manual cell counting was also performed at intervals of 61-90 and 91-150 minutes from baseline in the residual sample. Biochemistry analyses were performed in samples before and after centrifugation at baseline and at 91-150 minutes interval.

Results

At 91-150 minutes total cell count (P < 0.001), large lymphocytes (P = 0.007), neutrophils (P < 0.001) and phagocytes (P = 0.006) obtained by manual counting decreased and the number of disintegrated cells count increased (P = 0.016) compared to the baseline values. Considering method comparison, proportional difference between methods for all cell (sub)groups was obtained, whereas polymorphonuclears also showed the constant difference (y = 11.21 + 1.22x). Compared to centrifuged CSF, lower concentration of glucose and lactates were obtained in uncentrifuged samples (P < 0.001) at baseline.

Conclusions

Manual cell counting should be performed within 60 minutes as any delay can alter results. The same counting technique should be used to obtain longitudinally assessable results. Biochemistry tests are stable in uncentrifuged CSF up to 2.5 hours.

Use of the Sysmex XT-4000i hematology analyzer in the differentiation of cerebrospinal fluid cells in children

BACKGROUND

Routine analysis of pleocytosis and cellular composition of cerebrospinal fluid (CSF) is carried out with a phase-contrast microscope. The use of hematological analyzers seems to be an alternative to the manual method. The aim of the study was to assess the usefulness of the automated technique for counting and differentiating CSF cells in children.

METHODS

The study group consisted of 59 children (28 girls and 31 boys) aged from 4 to 17 years suffering from viral and bacterial meningitis. Children were divided into three subgroups according to CSF cell count: 1st group had a pleocytosis of 6-50 cells/µL, 2nd group-51-100 cells/µL, and 3rd group->100 cells/µL. A reference group involved 32 children (17 girls and 15 boys) aged from 2 to 18 years with a normal range of 0-5 cells/µL. Examination of CSF was performed in parallel by two different method, manual and automated.

RESULTS

The analysis of pleocytosis revealed that the values obtained by the manual method were statistically significantly lower in relation to the values obtained by automated technique in subgroups I and II. The number of mononuclear and polymorphonuclear cells in subgroups I, II, and III determined by both manual and automated methods was comparable.

CONCLUSION

We conclude that automated method cannot fully replace the previously used manual method and some of the dubious cases, such as samples with low pleocytosis rates or abnormal cells indicated by the analyzer, will still require microscopic examination.

Automated analysis for differentiating leukocytes in body fluids using the software "biological liquid application" on ADVIA2120/2120i hematology analyzer

INTRODUCTION

We evaluated the "Biological liquid application ADVIA2120" software for differentiating the percentage of polymorphonucleated (%PMN) and mononucleated cells (%MN) in ascitic, pleural, and peritoneal dialysis (PD) fluid.

METHODS

Biological fluid test results of 193 specimens obtained by automated methods (87 with and 106 without dedicated software) were compared with May-Grünwald-Giemsa (MGG) stained blood smears. Limit of detection (LoD) and quantitation (LoQ), repeatability, and inaccuracy were assessed.

RESULTS

Good agreement between the automated methods with dedicated software and the manual method for %PMN and %MN was obtained for leukocyte differentiation in ascitic and pleural fluids, while correlation with the manual method for PD fluid was poor, both with and without the dedicated software.

CONCLUSIONS

We demonstrated that the automated differentiation of leukocytes with dedicated software on the ADVIA2120 analyzer for body fluids is a good alternative to the microscopic reference method for peritoneal and pleural specimens, but not for PD fluids.

Evaluation of cell count and classification capabilities in body fluids using a fully automated Sysmex XN equipped with high-sensitive Analysis (hsA) mode and DI-60 hematology analyzer system

The XN series automated hematology analyzer has been equipped with a body fluid (BF) mode to count and differentiate leukocytes in BF samples including cerebrospinal fluid (CSF). However, its diagnostic accuracy is not reliable for CSF samples with low cell concentration at the border between normal and pathologic level. To overcome this limitation, a new flow cytometry-based technology, termed “high sensitive analysis (hsA) mode,” has been developed. In addition, the XN series analyzer has been equipped with the automated digital cell imaging analyzer DI-60 to classify cell morphology including normal leukocytes differential and abnormal malignant cells detection. Using various BF samples, we evaluated the performance of the XN-hsA mode and DI-60 compared to manual microscopic examination. The reproducibility of the XN-hsA mode showed good results in samples with low cell densities (coefficient of variation; % CV: 7.8% for 6 cells/μL). The linearity of the XN-hsA mode was established up to 938 cells/μL. The cell number obtained using the XN-hsA mode correlated highly with the corresponding microscopic examination. Good correlation was also observed between the DI-60 analyses and manual microscopic classification for all leukocyte types, except monocytes. In conclusion, the combined use of cell counting with the XN-hsA mode and automated morphological analyses using the DI-60 mode is potentially useful for the automated analysis of BF cells.

Evaluation of biological fluid analysis using the sysmex XN automatic hematology analyzer

BACKGROUND

Hematological cytometers with a biological fluid module could potentially correct the limitations of the manual chamber method. This study evaluates the agreement between the manual technique and the Sysmex XN-1000 analyzer for white blood cell (WBC) and red blood cell (RBC) counts, as well as for leukocyte differentiation in different types of fluids. This study also evaluates the advantages of incorporating the technique in routine laboratory work.

METHODS

One hundred and three fluid samples examined were 45 ascite (AF), 21 synovial (SF), 33 pleural (PF), and 31 cerebrospinal (CSF) fluid samples. All cell counting was performed with a Sysmex XN-1000 and a Fuchs-Rosenthal counting chamber. May Gründwald-Giemsa stain was used for manual WBC differentiation. The manual analysis data were obtained in duplicate by the same two observers. Passing-Bablok regression and the Kappa index were used to evaluate the interchangeability and concordance.

RESULTS

Good agreement was observed for WBC differentiation in all fluids and for WBC counts in SF and PF. An optimal Kappa index was obtained, which indicated agreement and clinical significance for WBC and RBC counts in CSF and for RBC counts in PF. There was disagreement for WBC and RBC analysis in AF, with significantly higher results from the Sysmex XN-1000 than from the manual method. A reduction in laboratory response time was observed when using the automatic method.

CONCLUSIONS

Except for AF, the Sysmex XN-1000 results agree with those of the manual method, although to different degrees depending on the fluid type. © 2017 International Clinical Cytometry Society.

Evaluation of Sysmex XN-1000 High-Sensitive Analysis (hsA) Research Mode for Counting and Differentiating Cells in Cerebrospinal Fluid

OBJECTIVES

Counting cells in cerebrospinal fluid (CSF) using automated analyzers is generally problematic due to low precision at low cell numbers. To overcome this limitation, Sysmex (Kobe, Japan) developed the high-sensitive analysis (hsA) research mode specifically for counting cells in fluids that contain low cell counts. We evaluated this mode by counting RBCs, WBCs, and differentiated WBCs in CSF samples.

METHODS

We analyzed 248 CSF samples using the hsA mode and compared these results with those obtained using the manual counting method. We also evaluated the linearity, detection limits, carryover, and precision of the hsA mode.

RESULTS

Using the hsA mode, the lower limit of quantification for RBCs and WBCs was 10 and 2 cells/μL, respectively. Comparing the two methods revealed good agreement with respect to WBCs (y = 1.08x + 0.52), RBCs (y = 1.07x + 0.00), lymphocytes (y = 1.00x + 0.00), neutrophils (y = 1.05x + 0.00), and monocytes (y = 0.88x + 0.07). Regression analysis for samples containing low WBCs (<10 cells/μL) and low RBCs (<50 cells/μL) also had good agreement, although a slight positive bias was found for RBCs. Linearity was good (r(2) ≥ 0.99) for all parameters evaluated. Carryover was negligible and never exceeded 0.04%.

CONCLUSIONS

The XN hsA research mode provides reliable cell counts in CSF samples, even in samples containing low numbers of WBCs and RBCs.

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.

Automated Cerebrospinal Fluid Cell Counts Using the New Body Fluid Mode of Sysmex UF-1000i

BACKGROUND

We evaluated the new body fluid module on Sysmex UF1000-i (UF1000i-BF) for analysis of white blood cell (WBC) and red blood cell (RBC) in cerebrospinal fluid (CSF).

METHODS

WBC and RBC counting were compared between UF1000i-BF and Fuchs-Rosenthal counting chamber in 67 CSF samples. This study also included the evaluation of between-day precision, limit of blank (LoB), limit of detection (LoD), functional sensitivity (limit of quantitation, LoQ), carryover and linearity. Diagnostic agreement for differentiation between normal and increased WBC counts (≥5.0 × 10(6) /L) was also assessed.

RESULTS

The agreement between UF1000i-BF and manual WBC counts was otpiaml in all CSF samples (r = 0.99; y = 1.05x + 0.09). A modest overestimation was noticed in samples with WBC < 30 × 10(6) /L (r = 0.95; y = 1.21x - 0.15). A good agreement was observed for RBC counts (r = 0.98; y = 1.15x + 0.55), particularly in samples with RBC ≥ 18 × 10(6) /L (r = 0.98; y = 1.01x + 8.90). Between-day precision was good, with coefficient of variations (CVs) lower than 7.2% for both WBC and RBC. The LoBs were 0.1 × 10(6) WBC/L and 1.2 × 10(6) RBC/L, the LoDs were 0.7 × 10(6) WBC/L and 5.5 × 10(6) RBC/L, the LoQs were 2.4 × 10(6) WBC/L and 18.0 × 10(6) RBC/L, respectively. Linearity was excellent (r = 1.00 for both WBC and RBC). Carryover was negligible. Excellent diagnostic agreement was obtained at 4.5 × 10(6) WBC/L cut-off (sensitivity, 100%; specificity, 97.4%).

CONCLUSION

The UF1000i-BF provides rapid and accurate WBC and RBC counts in clinically relevant values of CSF cells. The use of UF1000i-BF may hence allow to replace routine optical counting, except for samples displaying abnormal WBC counts or abnormal scattergram distribution, for which differential cell counts may still be required.

Flow cytometry for the microscopy of body fluids in patients with suspected infection

Automating the microscopy of body fluids is challenging, due to the wider range and lower concentrations of cells in these fluids, as opposed to blood, while the viscous nature of some of these fluids can also be problematic. This review shows that there have been major improvements and that newer flow cytometers can have remarkably low limits of quantitation for WBCs. Accurate counting of RBCs is still problematic with many flow cytometers, but this is of no clinical significance. Many flow cytometers can give reasonably accurate WBC differential counts, but detection of eosinophils and neoplastic or other nucleated cells which are not blood cells can still be problematic, hence fail-safe measures are recommended. Cerebrospinal fluid is the most challenging body fluid as it requires the ability to count and differentiate WBCs down to a 'normal range', which is much lower than the diagnostic cut-off values used for serous fluids; precision at or around the cerebrospinal fluid WBC normal range is reduced even with the best flow cytometers, but manual microscopy is even less precise.

Detection of malignant cells in serous body fluids by counting high-fluorescent cells on the Sysmex XN-2000 hematology analyzer

INTRODUCTION

The body fluid mode of the Sysmex XN-2000 hematology analyzer differentiates cells into mononuclear and polymorphonuclear white blood cells (WBC) and high-fluorescent cells (HFC). The aim of this study was to evaluate the performance of the HFC count for detecting malignant cells in serous body fluids.

METHODS

Two-hundred and thirty serous fluids were analyzed on the Sysmex XN body fluid mode. HFC were measured as relative count (HFC/100 WBC) and absolute count (HFC/μL). All samples were microscopically screened on cytospin slides for the presence of malignant cells.

RESULTS

Malignant cells were found by microscopic examination in 49 of 230 samples (21.3%). Malignant samples contained significantly higher percentages (10.2 vs. 2.6/100 WBC) and absolute numbers (65 vs. 10/μL) of HFC than nonmalignant samples (P < 0.001). Areas under the ROC curve for relative and absolute HFC count were 0.69 and 0.77, respectively. A cutoff level of ≥17 HFC/μL showed the best performance to predict malignancy, with 88% sensitivity and 61% specificity.

CONCLUSION

As serous body fluids will be more analyzed on automated analyzers in the future, HFC count can be a useful tool to select samples for microscopic review. Microscopic evaluation should be performed if HFC values are above a certain threshold (e.g. ≥17 HFC/μL) or in case of clinical suspicion of malignancy.

Body fluid cellular analysis using the Sysmex XN-2000 automatic hematology analyzer: focusing on malignant samples

INTRODUCTION

The majority of previous studies on body fluid (BF) mode of automatic hematology analyzer used nonmalignant BF samples. Here, we evaluated the BF mode on the recently launched Sysmex XN for counting blood cells, especially for malignant samples.

METHODS

A total of 405 BF specimens including 125 malignant samples were analyzed using both the automated method and manual microscopy.

RESULTS

In non-cerebrospinal fluids (CSF) samples, there was an agreement between two methods for WBC, RBC, polymorphonuclear, and mononuclear cell counts (R(2)  = 0.96, 0.94, 0.88, and 0.88, respectively). CSF samples showed slightly poorer correlations than other fluids. Exclusion of malignant samples significantly improved correlations in non-CSF samples, but not in CSF samples. High fluorescence-BF (HF-BF) cells were identified significantly more frequently in malignant samples compared to benign samples (17.8 and 4.15/100 WBC, respectively; P < 0.001). Receiver operating characteristic curve analysis demonstrated an HF-BF cell AUC of 0.791 using a cutoff value of 6.9/100 WBC for detecting malignant samples.

CONCLUSION

The BF mode on the Sysmex XN could be an alternative method for the manual counts in the BF analysis with a few drawbacks. However, if a concentration of HF-BF cells is greater than the given threshold, microscopic examination should be subsequently performed.

Automated white blood cell counts in cerebrospinal fluid using the body fluid mode on the platform Sysmex XE-5000

BACKGROUND

The Sysmex XE-5000 offers automated quantification of red blood cells and white blood cells (WBCs) in body fluids, with differentiation of polymorphonuclear cells (PMNs) and mononuclear cells (MNCs).

METHODS

We evaluated automated WBC counting in cerebrospinal fluid (CSF) using the body fluid mode on the Sysmex XE-5000, comparing it with flow cytometry as the reference method, and also with manual counting by microscopy. Experimental analysis for linearity and limit of detection was performed by diluting isolated WBCs in cell-free CSF. To study the ability to discriminate between PMNs and MNCs, samples were spiked using MNCs separated from peripheral blood. Comparison of WBC counts between a counting chamber and the XE-5000 was performed for 198 CSF samples.

RESULTS

In the experimental set-up, within-run (CV 19%) and between-day imprecision (CV 15.3%) in quantitating total number of WBC on XE-5000 was acceptable for WBC counts ≥ 25 × 10(6)/L. Compared with expected cell counts, mean bias was + 2.6% for flow cytometry, + 5.5% for XE-5000 and - 73.2% for manual counting. Differentiation between PMNs and MNCs was in concordance with flow cytometry. In comparisons of clinical CSF samples, overall agreement between the XE-5000 and manual counting was observed in 81% of the samples, but mean difference in WBC differentiation was higher for PMN (51.1 × 10(6)/L) than for MNC (7.95 × 10(6)/L).

CONCLUSION

Despite limited precision at low WBC counts, XE-5000 could be a favourable alternative to the labour-intensive, time-consuming and less reliable manual counting and cuts turnaround times in routine CSF-based diagnosis.

Comparison of donkey hemogram using the LaserCyte hematology analyzer, an impedance system, and a manual method

BACKGROUND

Donkeys are becoming increasingly important worldwide; therefore a reliable and accurate method of diagnosing disease is necessary. Flow cytometry-based hematologic analyzers are present in veterinary laboratories, but performance of LaserCyte has not been evaluated in donkeys.

OBJECTIVES

The objective of the study was to compare the results of donkey blood obtained from the LaserCyte with impedance and manual methods.

METHODS

Blood samples were collected from 84 healthy donkeys (1-20 years old) and measured with LaserCyte, Sysmex F-820 and manually. Agreement between methods was studied using Passing-Bablok test and Bland-Altman plots. Influence of blood abnormalities found on blood smears on LaserCyte counts was examined using Mann-Whitney or Kruskal-Wallis test. Intraassay precision was calculated.

RESULTS

Hematologic variables obtained from the LaserCyte were significantly different from those obtained with impedance or manual methods; numerous values were flagged. Agreement between LaserCyte and manual method was poor for the majority of variables, but agreement between LaserCyte and impedance was only poor for HCT, MCH, and MCHC. LaserCyte had an intraassay precision < 10% for RBC and platelet variables, and > 10% for WBC variables.

CONCLUSIONS

LaserCyte results were not interchangeable with results from other methods due to poor agreement. LaserCyte provided no additional hematologic variables or clinically relevant indices for donkey blood analysis. A large number of results were flagged, requiring the evaluation of blood smears. No benefits were found for the use of LaserCyte analyzer over the use of impedance or manual methods in this study. Specific software for LaserCyte for donkey blood would be beneficial.

Performance evaluation of the new hematology analyzer Sysmex XN-series

INTRODUCTION

The Sysmex XN-series is a new automated hematology analyzer designed to improve the accuracy of cell counts and the specificity of the flagging events.

METHODS

The basic characteristics and the performance of new measurement channels of the XN were evaluated and compared with the Sysmex XE-2100 and the manual method. Fluorescent platelet count (PLT-F) was compared with the flow cytometric method. The low WBC mode and body fluid mode were also evaluated. For workflow analysis, 1005 samples were analyzed on both the XN and the XE-2100, and manual review rates were compared.

RESULTS

All parameters measured by the XN correlated well with the XE-2100. PLT-F showed better correlation with the flow cytometric method (r(2)  = 0.80) compared with optical platelet count (r(2)  = 0.73) for platelet counts <70 × 10(9) /L. The low WBC mode reported accurate leukocyte differentials for samples with a WBC count <0.5 × 10(9) /L. Relatively good correlation was found for WBC counts between the manual method and the body fluid mode (r = 0.88). The XN made less flags than the XE-2100, while the sensitivities of both instruments were comparable.

CONCLUSION

The XN provided reliable results on low cell counts, as well as reduced manual blood film reviews, while maintaining a proper level of diagnostic sensitivity.

Technology and new fluorescence flow cytometry parameters in hematological analyzers

BACKGROUND

Modern hematological analyzers offer a series of new tests in addition to the differential blood cell count. Here, we provide a short overview of the technique and the new tests included in the hematological analyzers manufactured by the company Sysmex (Kobe, Japan). As introduced here, the resulting new extended blood cell count allows for the quantification of DNA- and RNA-rich, activated and/or precursor leukocyte subpopulations.

METHODS

To compare the different methods of blood cell counting, repetitive cell counting is carried out by hematological experts using microscopy and using the XE-5000 hematological analyzer.

RESULTS

The hematological analyzer delivers more-accurate results with respect to normal cells but microscopy is suited better to recognize and count pathological cells.

CONCLUSION

With the new hematological analyzers, several new hematological tests are made available as screening tools that were not possible previously using standard cell-counting procedures.

Cellular origin and diagnostic significance of high-fluorescent cells in cerebrospinal fluid detected by the XE-5000 hematology analyzer

INTRODUCTION

The Sysmex XE-5000 is a blood and body fluid analyzer able to differentiate cells into polymorphonuclear, mononuclear, and high-fluorescent cells (HFC). The identity of HFC in cerebrospinal fluid (CSF) has been uncertain; however, compatible with their high nucleic acid content, HFC could represent intrathecal tumor cells. Here, we studied the cellular origin and the diagnostic significance of HFC in CSF.

METHODS

Results of CSF examinations with the XE-5000 were analyzed in 65 CSF samples with and 126 CSF samples without tumor cells, as defined by manual microscopy of CSF cytospin preparations.

RESULTS

The XE-5000 detected HFC in 51 of 65 tumor cell-positive and in 33 of 126 tumor cell-negative CSF samples (sensitivity: 78.5%, specificity: 73.8%, positive likelihood ratio: 3.0, negative likelihood ratio: 0.29). The percentages of HFC and tumor cells in CSF samples correlated (r² = 0.41, P < 0.0001). Tumor cells escaped detection by the XE-5000 especially in CSF samples with a low percentage of tumor cells.

CONCLUSION

While this study identifies tumor cells as the predominant correlate of HFC in CSF, it suggests that measuring HFC is not an appropriate diagnostic test for intrathecal tumor cells. However, if HFC are incidentally detected in CSF, further evaluation by CSF microscopy seems mandatory.

Laboratory hematology in the history of Clinical Chemistry and Laboratory Medicine

Background: For the occasion of the 50th anniversary of the journal Clinical Chemistry and Laboratory Medicine (CCLM), an historic overview of papers that the journal has published in the field of laboratory hematology (LH) is presented.

Methods: All past volumes of CCLM were screened for papers on LH and these were categorized. Bibliographic data of these papers were also analyzed.

Results: CCLM published in total 387 LH papers. The absolute number of LH papers published annually showed a significant increase over the years since 1985. Also the share of LH papers demonstrated a steady increase (overall mean 5%, but mean 8% over the past 4 years). The most frequent category was coagulation and fibrinolysis (23.5%). Authors from Germany contributed the most LH papers to the journal (22.7%), followed by the Netherlands and Italy (16.3 and 13.2%, respectively). Recent citation data indicated that other publications cited LH review papers much more frequently than other types of papers.

Conclusions: The history of the journal reflects the emergence and development of laboratory hematology as a separate discipline of laboratory medicine.

Performance Evaluation of the Sysmex XE-5000 Hematology Analyzer for White Blood Cell Analysis in Cerebrospinal Fluid

Context.—The newest generation hematology analyzer, Sysmex XE-5000 (Sysmex Corporation, Kobe, Japan) is equipped with an improved body fluid analysis mode.

Objective.—To evaluate the applicability of the XE-5000 analyzer to white blood cell (WBC) analysis in cerebrospinal fluid (CSF).

Design.—A total of 425 routinely collected, consecutive CSF samples were included in the study. For a comparison of total WBC counts, the results of routine chamber counts were grouped into categories of 0 to 5 (n  =  330), &gt;5 to 10 (n  =  36), &gt;10 to 50 (n  =  39), &gt;50 to 200 (n  =  15), and &gt;200 (n  =  5) WBC/µL. Microscopic differential counts were performed using cytospins from 276 samples. Results were grouped according to the percent content of polymorphonuclear (PMN) cells, 0% to 25% (n  =  263), &gt;25% to 50% (n  =  7), &gt;50% to 75% (n  =  3), and &gt;75% to 100% (n  =  3) of WBC. Corresponding results of XE-5000 analysis were matched to these particular count categories.

Results.—For total WBC counts, the proportions of samples correctly classified by the XE-5000 from the percentage groups described above were 88%, 47%, 72%, 93%, and 100%, respectively. After the two lowest count categories were combined into one range of 0 to 10 WBC/µL, matches increased to 95%. For PMN counts in the 0% to 25% group, 37% of samples were misclassified by the XE-5000. Conversely, for samples with microscopic PMN counts of more than 25%, there was a trend toward underestimation by the XE-5000. Mismatches were most pronounced in samples with fewer than 10 WBC/µL.

Conclusions.—The Sysmex XE-5000 hematology analyzer yields valid total CSF cell counts and may be considered an acceptable alternative to the traditional chamber method, even for samples with low WBC counts. However, it cannot be recommended as a suitable alternative for manual differential cytologic workup.

Cell analysis in cerebrospinal fluid (CSF) using Sysmex® hematology analyzers XT-4000i and XE-5000: evaluation with CSF controls of the Joint German Society for Clinical Chemistry and Laboratory Medicine (DGKL)

In cerebrospinal fluid (CSF) analysis, hematology analyzers (HAs) Sysmex® XT-4000i and XE-5000, equipped with flow cytometry (FCM), were used to count cells and differentiate leukocytes into mononuclear and polymorphonuclear cells (MNCs, PMCs) applying body fluid mode. FCM was evaluated with 20 DGKL CSF controls containing viable human leukocytes and erythrocytes. HA values were compared with reference values by Passing/Bablok regression analysis to reveal conformity. Conformity of white blood cells (WBCs) was obtained with native leukocytes, counted in calibrated Fuchs-Rosenthal chamber as reference; red blood cell counts proved inaccurate. CV <40% with WBC counts <20 per μL impairs accuracy. Reference WBC differentiation was assayed using FACS Canto II™ and FC-500 SN with anti-CD45, anti-CD14, anti-CD16, anti-CD16/56 [Becton Dickinson (BD); Beckman Coulter (BC)]. BD FACS lysing solution®-no-wash-procedure was applied. BC pretreatment with Versalyse lysing solution was not recommended. MNCs (lymphocytes + monocytes) were significantly lower (∼14%) on both HAs; PMCs (granulocytes or sum of neutrophils + eosinophils + basophils: range 1-86 M/L) were significantly higher (∼2.2-fold). WBC HA differentiation is not reliable because MNC/PMC differentiation yielded lower and higher values than FACS-FCM references, respectively. This is attributed to incorrect discrimination of leukocytes with rounded/nonrounded nuclei; adding leukocytes with nonrounded nuclei to too low HA MNCs (about 40% not-activated) yielded P/B conformity; subtraction of leukocytes with nonrounded nuclei from elevated HA PMCs showed conformity (about 85% activated). Nucleus/activation state of leukocytes was assessed using microhistology. Sysmex XT-4000i and XE-5000 HAs systems are inappropriate for complete CSF cell analysis.

Automated vs. manual cerebrospinal fluid cell counts: a work and cost analysis comparing the Sysmex XE-5000 and the Fuchs-Rosenthal manual counting chamber

INTRODUCTION

Cerebrospinal fluid (CSF) cell counts are traditionally performed by manual microscopy using the Fuchs-Rosenthal counting chamber. This procedure is time-, labour- and cost-intensive and requires experienced laboratory staff.

METHODS

The Sysmex XE-5000 haematology analyzer offers a channel to quantify the total cell count of body fluids. We compared technical sensitivity and specificity, intra-assay variability, turn-around time (TAT) and costs for the determination of CSF cell counts between both methods.

RESULTS

The mean coefficients of variation (CV) for total cell counts in CSF of the Fuchs-Rosenthal chamber and the XE-5000 were 15.2% (range: 2.8-47.5%) and 12.5% (range: 1.9-50.6%). Setting the Fuchs-Rosenthal chamber as 'gold standard', our results revealed a sensitivity of 100% and a specificity of 75% for the XE-5000 to detect a pathological cell count (≥ 6 cells/μL), whereas the sensitivity and specificity to detect a severely pathological cell count (≥ 20 cells/μL) were 100% for both. Bland and Altman analysis revealed slightly higher cell counts with the XE-5000. The approximate duration of a single CSF cell count analysis was 635 s for the manual vs. 85 s for the automated method. Total analytical performance costs for the counting chamber were 6.74 EUR per mean analysis and 1.22 EUR for the XE-5000.

CONCLUSION

Our study revealed a lower mean CV for the total cell count for the XE-5000 method. The fully automated CSF cell count results in a 7.5-fold reduction in TAT and leads to a significant decrease in total analytical performance costs.

Performance of the Iris iQ®200 Elite analyser in the cell counting of serous effusion fluids and cerebrospinal drainage fluids

Aims

Evaluation of the Iris iQ®200 Elite analyser, initially designed for urinary cell counting, for the analysis of biological fluids (serous effusion fluids and cerebrospinal drainage fluids) and comparison of its performance with that of the manual microscopic method.

Methods

Routine samples (ascite fluids, pleural fluids and cerebrospinal fluids) were evaluated in terms of red blood cells and nucleated elements using the iQ®200 analyser and the manual method. The authors compared the reliability, repeatability and speed of the two techniques. In addition, the authors assessed the contribution of two different sample dilution processes to the improvement of iQ®200 analyser cytological results.

Results

Very good agreements were found between the two methods and between the two sample dilution processes. Regarding the repeatability, the coefficients of variation obtained with the iQ200 were slightly higher than those obtained by the manual method. Besides, the difference in the speed of the two methods was not significantly different for series with <10 samples.

Conclusions

The Iris iQ®200 Elite analyser has allowed us to obtain reliable results, equivalent to that of the manual method, for cell enumeration in biological fluids. Although the speed of this instrument needs to be improved for larger series of samples, it enables standardised and objective cytological results to be obtained and represents an alternative to the usual manual microscopic method. Moreover, automation of such analyses permits saving of technician time.