Performance Evaluation of High Fluorescence Lymphocyte Count: Comparability to Atypical Lymphocyte Count and Clinical Significance

Hematological parameters: is there a difference between those released by the hematological analyzer and to the customer?

OBJECTIVE

This study aimed to compare the hematological parameters released by hematological analyzers with those released in customer reports.

METHODS

We conducted a descriptive study in the laboratories of a medium-sized municipality in the state of Minas Gerais registered in the National Register of Health Establishments. Interviews were conducted using a questionnaire to obtain information regarding the parameters released by the analyzers and those available in the customer's report.

RESULTS

Sixteen laboratories were evaluated, and none of them released all the parameters obtained from the hematological analyzers to customers. The red blood cell distribution width was released in 88% of the laboratories, atypical lymphocytes in 70%, mean platelet volume in 50%, platelet distribution width and platelet count in 20%. No laboratory released information on reticulocytes, fraction of immature reticulocytes and immature granulocytes, nucleated erythrocyte count, immature platelet fraction and reticulocyte hemoglobin, and large platelet rate.

CONCLUSION

All evaluated clinical analysis laboratories had at least one parameter that was not released in the customer's report despite being released by the hematological analyzers. The lack of knowledge on the part of professionals about the clinical importance of each parameter of the complete blood count results in a loss in patient assessment, and it is important to include these parameters in the complete blood count report.

A More Comprehensive Clinical and Laboratory Characterization of 61 Acute HIV Infection Patients in Southwest China

Acute HIV infection (AHI), i.e., the early stage of HIV infection, plays an important role in immune system failure and HIV transmission, but most AHI patients are missed due to their non-specific symptoms. To facilitate the identification of patients with high AHI risk and reduction of missed diagnosis, we characterized 61 AHI patients in a Southwest China hospital with 4300 beds; specifically, we characterized their general clinical characteristics, evolution in results of a novel HIV screening assay called Elecsys^® HIV Duo, and by programming, we analyzed the ability of all routine laboratory tests (e.g., routine blood analysis) to identify AHI patients. Among 61 AHI patients, 85.2% were male and the median age was 42 (interquartile range, 25-62) years. A total of 61.9% of patients visit the emergency department first during AHI. Clinical presentation of AHI patients included fever, fatigue, chills, rash, and various respiratory, digestive, and nervous system symptoms. Two of three results from Elecsys^® HIV Duo show clear evolution trends: HIV P24 antigen decreased while HIV antibody increased in consecutive samples of nearly all patients. High fluorescence lymphocytes have a very high positive likelihood ratio (LR+) of 10.33 and a relatively high "rate of out-of-range tests" of 56.8% (21 in 37 patients who received this test had a result outside the reference range). In addition, we identified more than ten tests with LR+ greater than two. In summary, the emergency department is important for AHI screening. The evolution of HIV P24 Ag and HIV Ab and those laboratory tests with a high "rate of out-of-range tests" or high LR+ may aid the AHI identification and missed diagnosis reduction.

The clinical value of high fluorescent lymphocytes and smudge cells in the diagnosis of infectious mononucleosis

BACKGROUND

The diagnostic value of high fluorescent lymphocytes (HFLC) and smudge cells in diseases like sepsis has been confirmed. In this study, we explore the diagnostic value of HFLC and smudge cells for infectious mononucleosis (IM).

METHODS

Sixty-two IM patients, 67 healthy controls, 84 patients with upper respiratory tract virus infection, and 35 patients with malignant lymphoid diseases were enrolled. The complete blood counts and leukocyte differential counts are tested, and the smudge cells were manually counted.

RESULTS

The value of HFLC% and smudge cells of the IM group were significantly higher than those of healthy controls and disease controls (p < 0.05), and the HFLC% value of IM patients was positively correlated with the number of reactive lymphocytes (r = 0.265). When the cutoff value of HFLC% was 0.4%, and the diagnostic value of IM was high (AUC = 0.995). When the smudge cells >2/100 nucleated cells, it can show better (AUC = 1.000). When the cutoff value of the HFLC% was 1.2%, it can effectively distinguish IM patients from upper respiratory tract virus infection patients (AUC = 0.934); when smudge cells >16/100 nucleated cells, it also has high differential diagnosis value (AUC = 0.913). In addition, the AUC of the combination HFLC% and smudge cells for the differential diagnosis can be increased to 0.968. The performance value of single HFLC% (AUC = 0.942) for distinguishing IM from malignant lymphoid diseases was better than smudge cells and combine index with the cutoff value of 0.4%.

CONCLUSION

HFLC% and smudge cells can be used as effective indicators in the early diagnosis and differential diagnosis of IM.

Mature and Immature/Activated Cells Fractionation: Time for a Paradigm Shift in Differential Leucocyte Count Reporting?

Leucocytes, especially neutrophils featuring pro- and anti-cancerous characteristics, are involved in nearly every stage of tumorigenesis. Phenotypic and functional differences among mature and immature neutrophil fractions are well reported, and their correlation with tumor progression and therapy has emerging implications in modern oncology practices. Technological advancements enabled modern hematology analyzers to generate extended information (research parameters) during complete blood cell count (CBC) analysis. We hypothesized that neutrophil and lymphocyte fractions-related extended differential leucocytes count (DLC) parameters hold superior diagnostic utility over routine modalities. The present study was carried out over a four-and-a-half-year period wherein extended neutrophil (immature granulocyte [IG] and mature neutrophil [NEUT#&]), and lymphocyte (activated/high fluorescence lymphocyte count [HFLC] and resting lymphocyte [LYMP#&]) parameters were challenged over routine neutrophil [NEUT#] and lymphocyte [LYMP#] items in a study population of 1067 hematological neoplasm patients. Extending the classical statistical approaches, machine-learning-backed data visualization was used to explore trends in the study parameters. As a whole, extended neutrophil and lymphocyte count outperformed and was diagnostically more relevant than routine neutrophil and lymphocyte parameters by showing the least difference from their respective (gold-standard) manual DLC counts. The mature neutrophil count was compared to IG, and resting lymphocyte count was compared to HFLC by calling the function ‘correlation’ as a ‘clustering function’ for heatmap based visualization. The aforementioned study parameters displayed close clustering (rearrangement) for their respective study items by presenting distinct trends of equally valuable weights (deviated values), advocating fractions-based extended DLC reporting. Importantly, using a Bland and Altman analysis analogously to a manual neutrophil count, the mature neutrophil count [NEUT#&] remained unbiased since a routine neutrophil count [NEUT#] was found to be a negatively biased. The extended DLC-parameter-driven fractions-based reporting has superior diagnostic utility over classical routine approaches; this finding can largely minimize labor-intensive manual DLC practices, especially in hematology–oncology departments.

Hemocytometric characteristics of COVID-19 patients with and without cytokine Storm syndrome on the Sysmex XN-10 hematology analyzer

OBJECTIVES

COVID-19 is an ongoing global pandemic. There is an urgent need for identification and understanding of clinical and laboratory parameters related to progression towards a severe and fatal form of this illness, often preceded by a so-called cytokine-storm syndrome (CSS). Therefore, we explored the hemocytometric characteristics of COVID-19 patients in relation to the deteriorating clinical condition CSS, using the Sysmex XN-10 hematology analyzer.

METHODS

From March 1st till May 16th, 2020, all patients admitted to our hospital with respiratory complaints and suspected for COVID-19 were included (n=1,140 of whom n=533 COVID-19 positive). The hemocytometric parameters of immunocompetent cells in peripheral blood (neutrophils [NE], lymphocytes [LY] and monocytes [MO]) obtained upon admission to the emergency department (ED) of COVID-19 positive patients were compared with those of the COVID-19 negative ones. Moreover, patients with CSS (n=169) were compared with COVID-19 positive patients without CSS, as well as with COVID-19 negative ones.

RESULTS

In addition to a significant reduction in leukocytes, thrombocytes and absolute neutrophils, it appeared that lymphocytes-forward scatter (LY-FSC), and reactive lymphocytes (RE-LYMPHO)/leukocytes were higher in COVID-19-positive than negative patients. At the moment of presentation, COVID-19 positive patients with CSS had different neutrophils-side fluorescence (NE-SFL), neutrophils-forward scatter (NE-FSC), LY-FSC, RE-LYMPHO/lymphocytes, antibody-synthesizing (AS)-LYMPHOs, high fluorescence lymphocytes (HFLC), MO-SSC, MO-SFL, and Reactive (RE)-MONOs. Finally, absolute eosinophils, basophils, lymphocytes, monocytes and MO-FSC were lower in patients with CSS.

CONCLUSIONS

Hemocytometric parameters indicative of changes in immunocompetent peripheral blood cells and measured at admission to the ED were associated with COVID-19 with and without CSS.

Combined hematologic parameters to optimize review criteria on XE-5000

INTRODUCTION

Forty-one consensus review rules are presented to a large number of hematology laboratories worldwide, as suggested by the International Consensus Group for Hematology Review. Research on the review criteria has mainly focused on adjusting the threshold of each parameter to establish optimized criteria with better efficiency based on the consensus group criteria. This study aimed to optimize the review criteria by combining hematologic parameters on a Sysmex XE-5000 hematology analyzer (XE-5000).

MATERIAL AND METHODS

A total of 662 nucleated red blood cell (NRBC) and 406 atypical lymphocyte cell (AL) flagged samples were used to establish hematologic parameters associated with NRBC and AL, respectively. Another set of 1423 optimization samples were used to validate the optimized criteria of NRBC and AL by combining associative hematologic parameters. The efficiency of each set of criteria was compared and optimized to obtain better efficiency, an acceptable slide review rate, and a low false-negative rate.

RESULTS

In the optimization NRBC set combining triple parameters, compared with the default setting (P < .001), the slide review rate declined from 30.26% to 14.42%, and the efficiency increased from 75.65% to 91.02%. In the optimization AL set combining triple parameters, compared with the default setting (P < .001), the slide review rate declined from 40.60% to 11.80%, and the efficiency increased from 64.02% to 93.00%.

CONCLUSIONS

Based on the adjustment of Q-flag values combining associative hematologic parameters, the optimal criteria with a low false-negative rate not only might have a higher efficiency but also may significantly reduce the slide review rate.