Is the Hemocytometer Obsolete for Body Fluid Cell Counting?

Assessing total erythrocyte count as a potential attribute for estimating hemoglobin in Cholistani cattle

The main objective of the study was to confirm whether a specific and constant interrelationship exists between total erythrocyte count (TEC) and hemoglobin (Hb) concentration in Cholistani cattle blood and to navigate the potential of TEC for estimating Hb level in Cholistani cattle (n = 264) grouped as per gender (males, n = 122; females, n = 142) and age (young, n = 140; adults, n = 124). The TEC and Hb (HbD) estimation was carried out through veterinary hematology analyzer. The Hb was also calculated as TEC × 3 and was termed as HbC. Linear regression was implied, and accordingly, scatterplots were drawn between TEC, HbD, HbC, and corrected Hb (CHB). The regression prediction equation hence attained was used to deduce corrected hemoglobin (CHb). A significant (P ≤ 0.05) difference was noticed between HbD and HbC. A non-significant (P ≥ 0.05) difference was noticed, however, between HbD and CHb. Tests of level of agreement indicated a higher Cronbach's alpha and intraclass correlation coefficient (0.682 for average measures) for HbD and CHb as compared to that for HbD and HbC (0.559 for average measures). A convention of Hb concentration as three times of TEC (× 3) is not valid for Cholistani cattle. A different pen-side hematological formula, i.e., Hb (g/dL) = 0.66(TEC) + 6.1, however, provides a better estimate of Hb from the TEC in cattle blood. Using hemocytometry for TEC in the field, all the stakeholders associated with veterinary research, academics, and practice may benefit from this formula in resource-poor countries.

Reducing sources of variance in experimental procedures in in vitro research

Background: Lack of reproducibility in preclinical research poses ethical and economic challenges for biomedical science. Various institutional activities by society stakeholders of leading industrialised nations are currently underway with the aim of improving the situation. Such initiatives are usually concerned with high-level organisational issues and typically do not focus on improving experimental approaches per se. Addressing these is necessary in order to increase consistency and success rates of lab-to-lab repetitions.

Methods: In this project, we statistically evaluated repetitive data of a very basic and widely applied lab procedure, namely quantifying the number of viable cells. The purpose of this was to assess the impact of different parameters and instrumentations which may constitute sources of variance in this procedure.

Conclusion: By comparing the variability of data acquired under two different procedures, featuring improved stringency of protocol adherence, our project attempts to identify the sources and propose guidelines on how to reduce such fluctuations. We believe our work can contribute to tackling the repeatability crisis in biomedical research.

Performance of Abbott Alinity hq hematology analyzer for automated cell counting of body fluids

INTRODUCTION

Body fluid cell counting and differentiation provide essential information for diagnosis and monitoring of diverse pathologies. We evaluated the performance of the newly launched Abbott Alinity hq hematology analyzer for automated cell counting in body fluids and compared red blood cell (RBC) and total nucleated cell (TNC) counts with the Cell-Dyn Sapphire automated hematology analyzer. Differential counts were compared with microscopic differentiation on cytocentrifuged preparations.

METHODS

Background concentration limits, limit of detection (LOD), linearity, imprecision, functional sensitivity and carryover were evaluated. For method comparison, we collected 172 body fluids (17 continuous ambulatory peritoneal dialysis fluids, 56 cerebrospinal fluids and 99 serous fluids).

RESULTS

Background concentration limits were ≤1000 cells/μL for RBC counts and ≤3 cells/μL for TNC counts. The LOD was 1000 RBC/µL and 5 TNC/µL. Results from linear regression analysis revealed excellent linearity. Functional sensitivity was 3000 cells/µL for RBC counts and 50 cells/µL for TNC counts. Carryover was 0.6% and 0.1% for TNC and RBC, respectively. The Alinity hq shows good clinical performance.

CONCLUSION

We demonstrated comparable performance for body fluid cell counting between the Alinity hq analyzer and the Cell-Dyn Sapphire. The Alinity hq can be very useful as a screening tool for body fluid cell counting.

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 cell count in body fluids: a review

Body fluid cell counting provides valuable information for the diagnosis and treatment of a variety of conditions. Chamber cell count and cellularity analysis by optical microscopy are considered the gold-standard method for cell counting. However, this method has a long turnaround time and limited reproducibility, and requires highly-trained personnel. In the recent decades, specific modes have been developed for the analysis of body fluids. These modes, which perform automated cell counting, are incorporated into hemocytometers and urine analyzers. These innovations have been rapidly incorporated into routine laboratory practice. At present, a variety of analyzers are available that enable automated cell counting for body fluids. Nevertheless, these analyzers have some limitations and can only be operated by highly-qualified laboratory professionals. In this review, we provide an overview of the most relevant automated cell counters currently available for body fluids, the interpretation of the parameters measured by these analyzers, their main analytical features, and the role of optical microscopy as automated cell counters gain ground.

Improvement of cell counting method for Neubauer counting chamber

Background

We compared the cell counting accuracy of the conventional method and the improved method by using Neubauer counting chamber.

Methods

In the improved method, all the border cells were counted and then divided by two; while, in the conventional method, only border cells on the two boundaries (top and left) were counted.

Results

About 55.814% of the samples showed more accurate results by improved counting method, about 38.372% had more accurate results by conventional counting method, and about 5.814% were counted with similar counting error by both methods. The improved method had significantly smaller counting error than conventional method (P < .05). The distribution ratio of the border cells was an independent factor for counting accuracy (P < .05).

Conclusion

Together, the improved counting method can reduce the counting error of the Neubauer counting chamber to some extent, assess the distributing uniformity of border cells, and help to eliminate the samples with large differences in distribution.

Automated cell counts on CSF samples: A multicenter performance evaluation of the GloCyte system

OBJECTIVES

Automated cell counters have replaced manual enumeration of cells in blood and most body fluids. However, due to the unreliability of automated methods at very low cell counts, most laboratories continue to perform labor-intensive manual counts on many or all cerebrospinal fluid (CSF) samples. This multicenter clinical trial investigated if the GloCyte System (Advanced Instruments, Norwood, MA), a recently FDA-approved automated cell counter, which concentrates and enumerates red blood cells (RBCs) and total nucleated cells (TNCs), is sufficiently accurate and precise at very low cell counts to replace all manual CSF counts.

METHODS

The GloCyte System concentrates CSF and stains RBCs with fluorochrome-labeled antibodies and TNCs with nucleic acid dyes. RBCs and TNCs are then counted by digital image analysis. Residual adult and pediatric CSF samples obtained for clinical analysis at five different medical centers were used for the study. Cell counts were performed by the manual hemocytometer method and with the GloCyte System following the same protocol at all sites. The limits of the blank, detection, and quantitation, as well as precision and accuracy of the GloCyte, were determined.

RESULTS

The GloCyte detected as few as 1 TNC/μL and 1 RBC/μL, and reliably counted as low as 3 TNCs/μL and 2 RBCs/μL. The total coefficient of variation was less than 20%. Comparison with cell counts obtained with a hemocytometer showed good correlation (>97%) between the GloCyte and the hemocytometer, including at very low cell counts.

CONCLUSIONS

The GloCyte instrument is a precise, accurate, and stable system to obtain red cell and nucleated cell counts in CSF samples. It allows for the automated enumeration of even very low cell numbers, which is crucial for CSF analysis. These results suggest that GloCyte is an acceptable alternative to the manual method for all CSF samples, including those with normal cell counts.

A New Automated Technology for Cerebrospinal Fluid Cell Counts: Comparison of Accuracy and Clinical Impact of GloCyte, Sysmex XN, and Manual Methods

OBJECTIVES

The purpose of the study was to compare the performance of GloCyte (Advanced Instruments, Norwood, MA), a new semiautomated instrument for cerebrospinal fluid cell counting, with the manual hemocytometer method and the automated Sysmex XN (Sysmex, Kobe, Japan) body fluid mode. The clinical impact of replacing the manual method with either automated method was determined.

METHODS

Fifty-seven samples from 38 patients were analyzed by all three methods. Pearson correlation and Passing-Bablok regression were used to compare methods. Cytospin smears were reviewed on all samples, and clinical histories were obtained.

RESULTS

There was a strong linear relationship between the manual and automated methods for WBC counts ( R  = 0.988 for GloCyte; R  = 0.980 for Sysmex XN). Positive bias was absent or negligible for WBC counts less than 30/μL. GloCyte and manual RBC counts were equivalent. There were no samples for which replacement of manual WBC counts by automated counts would have changed the diagnosis. Both automated methods showed improved precision for WBC counts compared with the manual method.

CONCLUSIONS

Replacing manual WBC counts by GloCyte or Sysmex XN WBC counts would improve consistency of results without compromising diagnostic accuracy.