Automated determination of neutrophil VCS parameters in diagnosis and treatment efficacy of neonatal sepsis

Development and validation of a machine learning-based interpretable model for predicting sepsis by complete blood cell parameters

Background

Sepsis, a severe infectious disease, carries a high mortality rate. Early detection and prompt treatment are crucial for reducing mortality and improving prognosis. The aim of this research is to develop a clinical prediction model using machine learning algorithms, leveraging complete blood cell (CBC) parameters, to detect sepsis at an early stage.

Methods

The study involved 572 patients admitted to West China Hospital of Sichuan University between July 2020 and September 2021. Among them, 215 were diagnosed with sepsis, while 357 had local infections. Demographic information was collected, and 57 CBC parameters were analyzed to identify potential predictors using techniques such as the Least Absolute Shrinkage and Selection Operator (LASSO), Random Forest (RF), Support Vector Machine (SVM), and eXtreme Gradient Boosting (XGBoost). The prediction model was built using Logistic Regression and evaluated for diagnostic specificity, discrimination, and clinical applicability including metrics such as the area under the curve (AUC), calibration curve, clinical impact curve, and clinical decision curve. Additionally, the model's diagnostic performance was assessed on a separate validation cohort. Shapley's additive explanations (SHAP), and breakdown (BD) profiles were used to explain the contribution of each variable in predicting the outcome.

Results

Among all the machine learning methods' prediction models, the LASSO-based model (λ = min) demonstrated the highest diagnostic performance in both the discovery cohort (AUC = 0.9446, P < 0.001) and the validation cohort (AUC = 0.9001, P < 0.001). Furthermore, upon local analysis and interpretation of the model, we demonstrated that LY-Z, MO-Z, and PLT-I had the most significant impact on the outcome.

Conclusions

The predictive model based on CBC parameters can be utilized as an effective approach for the early detection of sepsis.

The diagnostic performance of mean neutrophil volume in neonatal sepsis: A systematic review and meta-analysis

BACKGROUND

There is a need for reliable diagnostic tests for early identification of sepsis to prevent neonatal mortality and antibiotic misuse. During sepsis, many immature neutrophils came into the bloodstream, altering the mean neutrophil volume (MNV) shown in the previous studies.

OBJECTIVES

To summarize the diagnostic performance of mean neutrophil volume (MNV) in neonatal sepsis from the published literature.

METHOD

Databases such as PubMed, Scopus, and Web of Science were searched from January 1990 to April 2023 for studies reporting MNV as a diagnostic test in neonatal sepsis. The pooled sensitivity, specificity, diagnostic odds ratio (DOR), and area under the curve (AUC) of the summary receiver operating characteristic (SROC) curve of MNV were estimated with reference blood culture-positive sepsis and clinical sepsis for meta-analysis.

RESULT

The diagnostic performance of MNV was analyzed in 1685 neonates, including 829 septic and 856 non-septic neonates, from six prospective studies. The pooled sensitivity and specificity of MNV were 0.87 and 0.75, respectively, for neonatal sepsis; the DOR was 20.01 (95% CI: 5.90-67.82); and the AUC of the SROC for MNV was 0.81 (95% CI: 0.69-0.88). Higgins I2 was 92.1% (95% CI: 85.5%-95.7%). The diagnostic performance of MNV was better during sub-group analysis of studies reporting culture-positive sepsis (DOR 85.61).

CONCLUSION

The diagnostic performance of MNV is moderate for neonatal sepsis. As the evidence originated from a small number of studies with marked heterogeneity, further large-scale diagnostic accuracy studies are recommended to resolve heterogeneity in the future.

Monocyte distribution width (MDW) kinetic for monitoring sepsis in intensive care unit

OBJECTIVES

Monocyte distribution width (MDW) is a measure of monocyte anisocytosis. In this study, we assessed the role of MDW, in comparison to C-reactive protein (CRP), procalcitonin (PCT), and lactate, as a screening and prognostic biomarker of sepsis in intensive care unit (ICU) by longitudinally measuring it in the first 5 days of hospital stay.

METHODS

We considered all consecutive patients admitted to the ICU. At admission, patients were classified as septic or not according to Sepsis-3 criteria. MDW, CRP, PCT, and lactate were measured daily in the first 5 days of hospitalization. ICU mortality was also recorded.

RESULTS

We included 193 patients, 62 with sepsis and 131 without sepsis (controls). 58% and 26 % of the patients, with and without sepsis respectively, died during ICU stay. MDW showed the highest accuracy for sepsis detection, superior to CRP, PCT, and lactate (AUC of 0.840, 0.755, 0.708, 0.622, respectively). At admission, no biomarker predicts ICU mortality in patients with sepsis. The kinetic of all biomarkers during the first 5 days of hospitalization was associated with ICU mortality. Noteworthy, above all, the kinetic of MDW showed the best accuracy. Specifically, an increase or decrease in MDW from day 1-4 and 5 was significantly associated with mortality or survival, respectively.

CONCLUSIONS

MDW is a reliable diagnostic and prognostic sepsis biomarker, better than traditional biomarkers.

Utility of VCS Parameters as a Cost-effective and Early Marker of Sepsis: A Hospital-based Study

Introduction

Sepsis is a life-threatening condition. Nowadays, hospitals rely on laboratory parameters like CRP and procalcitonin to detect sepsis. There is a need to evaluate and validate more accurate and early predictors of sepsis in critically ill patients. We analyzed volume, conductivity, and scatter (VCS) parameters of leukocytes in sepsis patients and compared them with the control group with no illness.

Materials and methods

It was a prospective case-control study. A total of 80 patients were studied with 40 sepsis cases and 40 controls. Peripheral smear examination was done in all the cases. Other parameters, such as WBC count, neutrophil%, absolute neutrophil count (ANC), High-sensitive C-reactive protein (hs-CRP), procalcitonin, and blood cultures were analyzed. We took the data of the patients from medical records and correlated it with other tests. Complete blood picture reports were generated by the Beckman Coulter LH series (LH 750 and 780). VCS parameters for neutrophils, lymphocytes and monocytes were compared between both groups. The results were analyzed using SPSS software (16.0 version).

Results

The age group was 20-85 years with male predominance. The mean neutrophil volume (MNV) and mean monocyte volume (MMV) were higher in the sepsis group when compared with the control group. The mean neutrophil conductivity and scatter was lower in the sepsis group and comparatively higher in the control group, but it was insignificant. The mean neutrophil volume values were higher in the sepsis group even with low total leukocyte count (TLC) when the patient had sepsis. There is no change in the mean lymphocyte VCS parameter and mean monocyte conductivity, scatter in both the groups.

Conclusion

The mean neutrophil volume and MMV are found to be good sensitive markers in the prediction of sepsis. Even when TLC is on the lower side in patients with sepsis, these parameters predict sepsis accurately. This helps clinicians to assess sepsis in patients at an early stage and has an important practical implication.

How to cite this article

Goyal H, Singhal A, Joseph M. Utility of VCS Parameters as a Cost-effective and Early Marker of Sepsis: A Hospital-based Study. Indian J Crit Care Med 2023;27(9):647-650.

Monocyte Distribution Width, a Novel Biomarker for Early Sepsis Screening and Comparison with Procalcitonin and C-Reactive Protein

Objectives Monocyte distribution width (MDW) can be used for the early recognition of sepsis. The study compared the diagnostic accuracy of the MDW with two well-known sepsis biomarkers, procalcitonin (PCT) and C-reactive protein (CRP).

Materials and Methods A study was conducted from July 2021 to October 2021, on 111 patients admitted to the Indus Hospital and Health Network. Patients from the ages of 1 to 90 years were enrolled if hospitalized for more than 24 hours for suspected sepsis to avoid inclusion of patients who had short-term stay in the emergency department. According to the Sequential Organ Failure Assessment score, the clinical team did the characterization of cases as with sepsis or without sepsis. SPSS version 24 was used, and the diagnostic accuracy of MDW was assessed and compared using the area under the curves (AUCs) acquired from receiver operating characteristic curves. Pearson's chi-square/Fisher's exact test (as per need) was applied to determine the association. A p-value of less than 0.05 was considered significant.

Results Among 111 patients, 81 (73%) patients were labeled with sepsis and 30 (27%) were without sepsis. We have reported significantly higher MDW, PCT, and CRP levels in septic patients (p < 0.001). The AUC of MDW was comparable with PCT (0.794). Significant cutoff value for the MDW was greater than 20.24 U with 86% sensitivity and 73% specificity.

Conclusion MDW may have a predictive ability similar to PCT and CRP in terms of sepsis and, thus, can be used as a standard parameter for the timely diagnosis of sepsis.

Monocyte distribution width (MDW) as a useful indicator for early screening of sepsis and discriminating false positive blood cultures

BACKGROUND

Severe sepsis and septic shock are the leading cause of in-hospital death. As sepsis progresses, expression and activity of endogenous mediators of inflammation change. Early detection of biomarkers can play a role in sepsis screening and in improvement of patient outcomes. Recent studies suggest that increase in monocyte volume may be helpful in early detection of sepsis. Therefore, we evaluated the utility of monocyte distribution width (MDW) for the early assessment of sepsis compared with the blood culture and other inflammatory biomarkers.

METHODS

Medical records of 1,404 patients (aged ≥19 years) who were admitted to the emergency department owing to clinically suspected infectious disease and requested blood cultures from Oct 2019 to Jan 2021 were reviewed. The patients were grouped based on Sepsis-3 criteria. They had undergone other laboratory tests to evaluate their clinical status. MDW was analyzed using DxH900 hematology analyzer (Beckman Coulter, Brea, California, USA). To determine the diagnostic performance of MDW, C-reactive protein (CRP), and procalcitonin (PCT) for sepsis, the area under the curve (AUC) of receiver operating characteristics curves and their sensitivity and specificity were measured.

RESULTS

Among 1,404 patients, 520 patients were designated the sepsis group based on Sepsis-3 criteria. In the sepsis group, MDW value was 24.1 (median, IQR 21.6-28.1); AUC values for MDW, CRP, and PCT were 0.67 (95% CI, 0.64-0.69), 0.66 (95% CI, 0.63-0.68), and 0.75 (95% CI, 0.72-0.77), respectively. For diagnosis of the sepsis, the cut-off value of MDW was 21.7 (sensitivity 74% and specificity 54%). Measured values of MDW were higher for the blood culture positive group than that of the blood culture contamination group (P<0.001, 95% CI, -5.9 to -3.0) or blood culture negative group (P<0.001, 95% CI = -5.8 to -4.2).

CONCLUSIONS

MDW is a new hematological parameter that is simultaneously calculated during complete blood cell counting by Beckman Coulter hematology analyzer. MDW is expected to serve as a useful indicator for early screening of sepsis in conjunction with CRP and PCT. MDW is especially useful for sepsis assessment in patients with a suspected infection. MDW can also assist in discriminating false positive blood cultures.

Investigating Morphological Changes of T-lymphocytes after Exposure with Bacterial Determinants for Early Detection of Septic Conditions

Sepsis is a leading cause of morbidity and mortality, annually affecting millions of people worldwide. Immediate treatment initiation is crucial to improve the outcome but despite great progress, early identification of septic patients remains a challenge. Recently, white blood cell morphology was proposed as a new biomarker for sepsis diagnosis. In this proof-of-concept study, we aimed to investigate the effect of different bacteria and their determinants on T-lymphocytes by digital holographic microscopy (DHM). We hypothesize that species- and strain-specific morphological changes occur, which may offer a new approach for early sepsis diagnosis and identification of the causative agent. Jurkat cells as a model system were exposed to different S. aureus or E. coli strains either using sterile determinants or living bacteria. Time-lapse DHM was applied to analyze cellular morphological changes. There were not only living bacteria but also membrane vesicles and sterile culture supernatant-induced changes of cell area, circularity, and mean phase contrast. Interestingly, different cellular responses occurred depending on both the species and strain of the causative bacteria. Our findings suggest that investigation of T-lymphocyte morphology might provide a promising tool for the early identification of bacterial infections and possibly discrimination between different causative agents. Distinguishing gram-positive from gram-negative infection would already offer a great benefit for the proper administration of antibiotics.

Comparison of the diagnostic accuracy of monocyte distribution width and procalcitonin in sepsis cases in the emergency department: a prospective cohort study

Background

Early diagnosis and treatment of patients with sepsis reduce mortality significantly. In terms of exploring new diagnostic tools of sepsis, monocyte distribution width (MDW), as part of the white blood cell (WBC) differential count, was first reported in 2017. MDW greater than 20 and abnormal WBC count together provided a satisfactory accuracy and was proposed as a novel diagnostic tool of sepsis. This study aimed to compare MDW and procalcitonin (PCT)’s diagnostic accuracy on sepsis in the emergency department.

Methods

This was a single-center prospective cohort study. Laboratory examinations including complete blood cell and differentiation count (CBC/DC), MDW, PCT were obtained while arriving at the ED. We divided patients into non-infection, infection without systemic inflammatory response syndrome (SIRS), infection with SIRS, and sepsis-3 groups. This study’s primary outcome is the sensitivity and specificity of MDW, PCT, and MDW + WBC in differentiating septic and non-septic patients. In addition, the cut-off value for MDW was established to maximize sensitivity at an optimal level of specificity.

Results

From May 2019 to September 2020, 402 patients were enrolled for data analysis. Patient number in each group was: non-infection 64 (15.9%), infection without SIRS 82 (20.4%), infection with SIRS 202 (50.2%), sepsis-3 15 (7.6%). The AUC of MDW, PCT, and MDW + WBC to predict infection with SIRS was 0.753, 0.704, and 0.784, respectively (p < 0.01). The sensitivity, specificity, PPV, and NPV of MDW using 20 as the cutoff were 86.4%, 54.2%, 76.4%, and 70%, compared to 32.9%, 88%, 82.5%, and 43.4% using 0.5 ng/mL as the PCT cutoff value. On combing MDW and WBC count, the sensitivity and NPV further increased to 93.4% and 80.3%, respectively. In terms of predicting sepsis-3, the AUC of MDW, PCT, and MDW + WBC was 0.72, 0.73, and 0.70, respectively. MDW, using 20 as cutoff, exhibited sensitivity, specificity, PPV, and NPV of 90.6%, 37.1%, 18.7%, and 96.1%, respectively, compared to 49.1%, 78.6%, 26.8%, and 90.6% when 0.5 ng/mL PCT was used as cutoff.

Conclusions

In conclusion, MDW is a more sensitive biomarker than PCT in predicting infection-related SIRS and sepsis-3 in the ED. MDW < 20 shows a higher NPV to exclude sepsis-3. Combining MDW and WBC count further improves the accuracy in predicting infection with SIRS but not sepsis-3.

Trial registration The study was retrospectively registered to the ClinicalTrial.gov (NCT04322942) on March 26th, 2020.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-06999-4.

Diagnosis of neonatal sepsis: the past, present and future

Sepsis remains a significant cause of neonatal mortality and morbidity, especially in low- and middle-income countries. Neonatal sepsis presents with nonspecific signs and symptoms that necessitate tests to confirm the diagnosis. Early and accurate diagnosis of infection will improve clinical outcomes and decrease the overuse of antibiotics. Current diagnostic methods rely on conventional culture methods, which is time-consuming, and may delay critical therapeutic decisions. Nonculture-based techniques including molecular methods and mass spectrometry may overcome some of the limitations seen with culture-based techniques. Biomarkers including hematological indices, cell adhesion molecules, interleukins, and acute-phase reactants have been used for the diagnosis of neonatal sepsis. In this review, we examine past and current microbiological techniques, hematological indices, and inflammatory biomarkers that may aid sepsis diagnosis. The search for an ideal biomarker that has adequate diagnostic accuracy early in sepsis is still ongoing. We discuss promising strategies for the future that are being developed and tested that may help us diagnose sepsis early and improve clinical outcomes. IMPACT: Reviews the clinical relevance of currently available diagnostic tests for sepsis. Summarizes the diagnostic accuracy of novel biomarkers for neonatal sepsis. Outlines future strategies including the use of omics technology, personalized medicine, and point of care tests.

Monocyte distribution width (MDW) as a screening tool for sepsis in the Emergency Department

Objectives The diagnosis of sepsis in the Emergency Department (ED) is challenging and a reliable biomarker is needed. The current study aimed to evaluate the diagnostic accuracy of monocyte distribution width (MDW) for the early identification of sepsis in the ED. Methods We performed a large observational study including consecutive adult patients (≥18 years of age) presenting to the ED between September and November 2019, with an order for complete blood count (CBC) evaluation. A total of 2,215 patients were enrolled and classified based on Sepsis-2 criteria as the control group (1,855), infection group (172), Systemic Inflammatory Response Syndrome (SIRS) group (100), and sepsis group (88). Results MDW levels were higher in patients with sepsis than in all other groups (p<0.001). ROC curve analysis showed an optimal diagnostic accuracy of MDW for sepsis prediction at a cut-off point of 23.5, with an AUC of 0.964, sensitivity and specificity of 0.920 and 0.929, respectively. Conclusions Our findings encourage further investigation to validate the use of MDW as a screening tool for the early identification of patients at risk of sepsis in the ED.

Clinical impact of monocyte distribution width and neutrophil-to-lymphocyte ratio for distinguishing COVID-19 and influenza from other upper respiratory tract infections: A pilot study

The coronavirus disease 2019 (COVID-19) has become a pandemic. Rapidly distinguishing COVID-19 from other respiratory infections is a challenge for first-line health care providers. This retrospective study was conducted at the Taipei Medical University Hospital, Taiwan. Patients who visited the outdoor epidemic prevention screening station for respiratory infection from February 19 to April 30, 2020, were evaluated for blood biomarkers to distinguish COVID-19 from other respiratory infections. Monocyte distribution width (MDW) ≥ 20 (odds ratio [OR]: 8.39, p = 0.0110, area under curve [AUC]: 0.703) and neutrophil-to-lymphocyte ratio (NLR) < 3.2 (OR: 4.23, p = 0.0494, AUC: 0.673) could independently distinguish COVID-19 from common upper respiratory tract infections (URIs). Combining MDW ≥ 20 and NLR < 3.2 was more efficient in identifying COVID-19 (AUC: 0.840). Moreover, MDW ≥ 20 and NLR > 5 effectively identified influenza infection (AUC: 0.7055). Thus, MDW and NLR can distinguish COVID-19 from influenza and URIs.

Automated leukocyte parameters are useful in the assessment of myelodysplastic syndromes

BACKGROUND

Study utility of seven automated VCS parameters (V-volume, C-conductivity and S-scatter) in leukocytes as an objective read-out of dysplasia in Myelodysplastic Syndromes (MDS).

METHODS

Peripheral blood was analyzed by Beckman-Coulter DxH800 hematology analyzer in 43 patients with low-grade, high-grade MDS and 21 control individuals. The differences in mean (MN) and standard deviation (SD) of each parameter were examined. The optimal sensitivity and specificity to predict MDS were determined by statistical analysis.

RESULTS

In neutrophils, all means of the light scatters were significantly lower in high-grade MDS than in the control group. Mean median angle light scatter (MN-MALS-NE) and mean upper median angle light scatter (MN-UMALS-NE) were significantly different between low-grade MDS and control patients. MN-MALS-NE as a MDS predictor revealed 63% sensitivity and 67% specificity with a cutoff value of ≤133. SDs of each parameter in neutrophils differed significantly among three groups. SD of neutrophil upper median angle light scatter (SD-UMALS-NE) had 77% sensitivity and 82% specificity (cutoff value of ≥11.16) to predict MDS.

CONCLUSIONS

MDS patients have a significant decrease with a linear trend in VCS parameters in neutrophils, indicating cell dysplasia. The degree of the heterogeneity measured by SD is the most predictive of MDS.

Reviewing the value of leukocytes cell population data (CPD) in the management of sepsis

Sepsis is a medical emergency that describes the body's systemic immune response to an infection and can lead to end-stage organic dysfunction and death. Despite the advances in understanding the pathophysiology of this syndrome and therapies, sepsis remains one of the leading causes of morbidity and mortality in critically ill patients. Early diagnosis and rapid intervention are essential to improve outcomes, which inspired the concept "golden hour," during which the correction of shock and organic dysfunction can improve the patients' outcomes. But the initial presentation of sepsis is often nonspecific and its severity is difficult to assess. Anomalies in temperature, heart and respiratory rates and leukocyte counts are manifestations of systemic inflammatory response syndrome (SIRS). Diagnosis, management and follow-up of patients with sepsis remains a challenge, and diverse biomarkers have been proposed for the timely diagnosis and prognosis of septic patients: lactic acid, procalcitonin (PCT), C-reactive protein, immature granulocytes. The host's initial response to infection is a humoral, cellular and neuroendocrine reaction to infection, and leukocytes interact with endothelial cells. The new generation of hematological analyzers incorporates technological innovations allowing to expand the information derived from the complete blood count: new leukocyte derived parameters are emerging as potentially useful markers in different clinical situations. Additional research parameters cell population data (CPD), characterizing different leukocyte populations have become available, and preliminary observations suggest their utility in the diagnosis of sepsis. This review emphasizes the value of CPD, reported by modern cellular counters for early recognition of sepsis, and therefore the potential improvement in patient outcomes.

Volume, conductivity, and scatter parameters of leukocytes as early markers of sepsis and treatment response

INTRODUCTION:

Morphologic changes in the size and granularity of leukocytes seen in sepsis could be measured using the volume, conductivity, and scatter (VCS parameters) from the automated hematology analyzers. The objective of this study is to find the clinical usefulness of VCS parameters as possible indicators of sepsis and to determine the effect of treatment on these parameters.

METHODS:

This observational study was conducted in a tertiary level hospital in India. Hemogram and VCS parameters obtained from LH 750 (Beckman coulter, Fullerton, CA) from 134 proven blood culture-positive cases of sepsis were reviewed on the day of culture positivity (day 0), day 3, and day 7 were analyzed and compared with those of samples from otherwise healthy 100 participants. Statistical analysis of data was done, and cutoff value was established using receiver-operator characteristic curve.

RESULTS:

Out of 134 culture-positive cases, 55.2% (n = 74) Gram-negative and 44.8% (n = 60) Gram-positive bacteria were isolated. The mean neutrophil volume (MNV) and mean monocyte volume (MMV) were higher in the sepsis group compared to that of the control group (165.43 ± 18.21 vs. 140.59 ± 7.6, P = 0.001 for MNV and 179.8 ± 14.16 vs. 164.54 ± 9.6, P = 0.001 for MMV). A significant decrease in MNV and MMV was observed with the initiation of the treatment. Significant changes in scatter and conductivity parameters were also noticed. A cutoff value of 150.2 for MNV gave a sensitivity and specificity of 79.1% and 95%, respectively, with an area under the curve (AUC) of 92.3%. With a cutoff of 168.3, MMV had a sensitivity of 80.6% and specificity of 77.5%, AUC of 83%.

CONCLUSION:

VCS parameters such as MNV and MMV can be easily obtained by an automated hematology analyzer and could be used for early detection and therapeutic response in sepsis.

Effects of Smoking on Volume, Conductivity and Scatter Parameters of Leukocytes

Aim: In this study, we aimed to determine changes in leukocytes volume, conductivity and scatter parameters in smokers compared to non-smokers. Methods: A total of 117 individuals (45 smokers and 72 non-smokers) were included in the study. While those who smoked at least 10 pack-years were included in the case group, those who never smoked at all were included in the control group. Results: While there was a statistically significant difference in mean neutrophil volume, mean neutrophil conductivity, mean lymphocyte conductivity, mean lymphocyte scatter, mean monocyte volume, mean monocyte conductivity, mean monocyte scatter, mean eosinophil conductivity values between the two groups, there was no statistically significant difference in mean neutrophil scatter, mean lymphocyte volume, mean eosinophil volume, mean eosinophil scatter values between the two groups. Conclusion: This study showed that smoking affected volume, conductivity and scatter parameters. Clinicians should consider whether the patient smokes if they want to diagnose any diseases using volume, conductivity and scatter parameters. Keywords: smoking, leukocytes, conductivity, scattering, neutrophils

Neutrophil Volume, conductivity and scatter (VCS) as a screening tool in neonatal sepsis

The initial evaluation of a suspected sepsis in a neonate is always challenging. There are many methods to screen a neonate with suspected sepsis. One of newer method is to assess the changes in neutrophil volume conductivity and scatter. The objective of this study was to establish changes in Neutrophil volume conductivity scatter (VCS) in neonatal sepsis and to determine appropriate cut off levels using receiver operating characteristic (ROC) curves. Neonates with suspected sepsis were evaluated with blood counts, culture and neutrophil VCS parameters. Based on these parameters neonates were classified into sepsis group (Blood culture positive), Probable sepsis group (clinical course consistent with sepsis and positive sepsis screen and negative blood culture), No sepsis group (Clinical course not suggestive of sepsis with negative sepsis screen and blood culture). A total of 304 neonates were included in the study of which 144 were in sepsis group and 160 in no sepsis group respectively. Among the neutrophil VCS parameters there was significant difference between the groups with respect to mean neutrophil volume (MNV) and volume distribution width (VDW) (180 vs 163 vs 150) (p < 0.01). MNV and VDW had good sensitivity (95%, 82%) and specificity (86%, 74%) for diagnosis of sepsis. In conclusion, Neutrophil VCS parameters, especially MNV, can be incorporated with other sepsis screen parameters in diagnosis of neonatal sepsis.

A Novel Implementation of Magnetic Levitation to Quantify Leukocyte Size, Morphology, and Magnetic Properties to Identify Patients With Sepsis

BACKGROUND

We have developed a novel, easily implementable methodology using magnetic levitation to quantify circulating leukocyte size, morphology, and magnetic properties, which may help in rapid, bedside screening for sepsis.

OBJECTIVE

Our objectives were to describe our methodological approach to leukocyte assessment, and to perform a pilot investigation to test the ability of magnetic levitation to identify and quantify changes in leukocyte size, shape, density, and/or paramagnetic properties in healthy controls and septic patients.

METHODS

This prospective, observational cohort study was performed in a 56,000/y visit emergency department (ED) and affiliated outpatient phlebotomy laboratory. Inclusion criteria were admittance to the hospital with suspected or confirmed infection for the septic group, and we enrolled the controls from ED/outpatient patients without infection or acute illness. The bench-top experiments were performed using magnetic levitation to visualize the leukocytes. We primary sought to compare septic patients with noninfected controls and secondary to assess the association with sepsis severity. Our covariates were area, length, width, roundness, and standard deviation (SD) of levitation height. We used unpaired t test and area under the curve (AUC) for the assessment of accuracy in distinguishing between septic and control patients.

RESULTS

We enrolled 39 noninfected controls and 22 septic patients. Our analyses of septic patients compared with controls showed: mean cell area in pixels (px) 562 ± 111 vs. 410 ± 45, P < 0.0001, AUC = 0.89 (0.80-0.98); length (px), 29 ± 2.5 vs. 25 ± 1.9, P < 0.0001, AUC = 0.90 (0.83-0.98); and width (px), 27 ± 2.4 vs. 23 ± 1.5, P < 0.0001, AUC = 0.92 (0.84-0.99). Cell roundness: 2.1 ± 1.0 vs. 2.2 ± 1.2, P = 0.8, AUC = 0.51. SD of the levitation height (px) was 72 ± 25 vs. 47 ± 16, P < 0.001, AUC = 0.80 (0.67-0.93).

CONCLUSIONS

Septic patients had circulating leukocytes with especially increased size parameters, which distinguished sepsis from noninfected patients with promising high accuracy. This portal-device compatible technology shows promise as a potential bedside diagnostic.

Comparison of Monocyte Distribution Width (MDW) and Procalcitonin for early recognition of sepsis

We carried out a prospective observational study to evaluate whether Monocyte Distribution Width (MDW) may play a role in identifying patients with sepsis in comparison with Procalcitonin (PCT). We prospectively enrolled all consecutive patients hospitalized at the Infectious Diseases Unit of Pescara General Hospital for bacterial infection or sepsis. MDW values were collected for all patients. Clinical characteristics, demographic data, past and present medical history, microbiological results, PCT, as well as neutrophil and monocytes indices at entry were compared in the 2 groups. Two-hundred-sixty patients were enrolled, 63.5% males, aged 59.1±19.5 years. Sepsis was diagnosed in 105 (40.4%); in 60 (57.1%) at least 1 microorganism was isolated from blood cultures. In multivariate models, MDW as a continuous variable (OR:1.57 for each unit increase; 95%CI: 1.31–1.87, p<0.001) and PCT˃1 ng/mL (OR: 48.5; 95%CI: 14.7–160.1, p<0.001) were independently associated with sepsis. Statistical best cut points associated with sepsis were 22.0 for MDW and 1.0 ng/mL for PCT whereas MDW values<20 were invariably associated with negative blood cultures. At ROC curve analysis, the AUC of MDW (0.87) was nearly overlapping that of PCT (0.88). Our data suggest that incorporating MDW within current routine WBC counts and indices may be of remarkable use for detection of sepsis. Further research is warranted.

The Leukocyte VCS Parameters Compared with Procalcitonin, Interleukin-6, and Soluble Hemoglobin Scavenger Receptor sCD163 for Prediction of Sepsis in Patients with Cirrhosis

Background

Patients with liver cirrhosis have a high risk of sepsis and a poor prognosis. Recently, a new standard for sepsis (Sepsis-3) has been proposed in the general population. The Coulter Lh 750 hematology analyzer can evaluate mean volume, conductivity, scatter, and distribution width of leukocyte. We tried to use Sepsis-3 criteria to study the diagnostic value of volume, conductivity, and scattering (VCS) parameters in sepsis and infection in patients with liver cirrhosis compared with traditional infection markers (PCT, IL-6, sCDl63).

Methods

A blinded, cohort study was conducted in three different ED populations within three affiliated hospitals. A total of 249 patients with liver cirrhosis were enrolled in the study. According to the “Sepsis-3” consensus criteria, clinical history, and laboratory examination, the subjects were divided into sepsis (n = 54), patients with infections (n = 95), and patients without systemic infections (n = 100). The blood samples of the patients were collected at the time of ED admission and were evaluated for the detection of sepsis.

Results

The differences of MNV, MNS, MMV, MMS, MLV, NDW, and MDW in the three groups were statistically significant. In the diagnosis of sepsis in patients with liver cirrhosis, the sensitivity of combined detection of MMV and MDW was 88.89%; the specificity was 74%. This sensitivity was significantly better than the 83.3% achieved using 0.97 mg/L as the cutoff for sCD163. In the diagnosis of infection in cirrhosis, the sensitivity of combination of MNV and MMS was increased to 86.32%; the specificity was 92%. The sensitivity was the same as that achieved by using 0.31 ng/mL as the cutoff value of PCT, but the specificity increased.

Conclusion

The leukocyte VCS parameter could be potential parameters for indicating sepsis and infection in patients with liver cirrhosis. The combined detection of MMV and MDW seemed to be helpful for the diagnosis of sepsis in these patients, and the combination of MNV and MMS could better indicate infection for them.

Point of care technologies for sepsis diagnosis and treatment

Sepsis is a rapidly progressing, life threatening immune response triggered by infection that affects millions worldwide each year. Current clinical diagnosis relies on broad physiological parameters and time consuming lab-based cell culture. If proper treatment is not provided, cases of sepsis can drastically increase in severity over the course of a few hours. Development of new point of care tools for sepsis has the potential to improve diagnostic speed and accuracy, leading to prompt administration of appropriate therapeutics, thereby reducing healthcare costs and improving patient outcomes. In this review we examine developing and commercially available technologies to assess the feasibility of rapid, accurate sepsis diagnosis, with emphasis on point of care.

Evaluation of haematological and volume, conductivity and scatter parameters of leucocytes for aetiological diagnosis of undifferentiated fevers

Background

In this follow-up study, we aimed to establish the cut-off values of the volume, conductivity and scatter (VCS) parameters of leucocytes that significantly differ in dengue fever, malaria, scrub typhus and enteric fever, as described in our pilot study.

Methods

A prospective observational case-control study was undertaken on patients with an established diagnosis of acute malaria (n=476), dengue fever (n=927), scrub typhus (n=425), bacterial sepsis (n=1598) or enteric fever (n=885) and the haematological and VCS data obtained by the Coulter LH 750 analyser were compared with controls.

Results

Malaria significantly altered the platelet count and plateletcrit. The cut-offs for the monocyte volume, lymphocyte volume, neutrophil volume, neutrophil volume distribution width, lymphocyte volume distribution width, monocyte volume distribution width and neutrophil conductivity distribution width had 90% negative predictive values (NPVs) for malaria. Except for the proportion of monocytes, lymphocyte scatter distribution width and platelet distribution width, a >70% positive (PPV) and negative predictive value (NPV) for dengue was noted in all the haematological and VCS parameters analysed. While the cut-offs determined in scrub typhus had a good (>80%) PPV and NPV, a significant difference was seen in neutrophil, monocyte and lymphocyte conductivities, but with low sensitivity, specificity, PPV and NPV in enteric fever.

Conclusions

Aetiology-specific changes occur both in numbers as well as in VCS properties in acute fevers. Formulae and/or algorithms need to be utilized to realize the full potential of the VCS technology.

Cytomorphometric Neutrophil and Monocyte Markers May Strengthen the Diagnosis of Sepsis

BACKGROUND:

The diagnosis of sepsis is challenging in the absence of a gold standard test. Recent studies have explored the role of neutrophil and monocyte volume, conductivity, and scatter (VCS), derived from automated hematology analyzers, in diagnosing sepsis. We assessed the diagnostic accuracy of VCS parameters in critically ill patients with sepsis.

METHODOLOGY:

In this prospective study, VCS parameters, procalcitonin, and C-reactive protein (CRP) were assessed in patients with proven sepsis (cases) and 2 control groups (intensive care unit [ICU] patients without sepsis and healthy blood donors). The diagnostic property of each test was explored by calculating sensitivity, specificity, negative and positive predictive values, and area under the curve (AUC).

RESULTS:

The study included 65 patients with sepsis, 58 nonseptic ICU controls, and 98 blood donors. Procalcitonin and CRP were not significantly different ( P > .06) between patients with sepsis and nonseptic patients. Mean (95% confidence interval [CI]) neutrophil volume (MNV) was significantly higher ( P < .001) in patients with sepsis (165.5; 95%CI 161.6-169.4) than in nonseptic (157.3; 95%CI 154.6-160.1) patients and donors (148.9; 95%CI 147.9-150). A similar pattern was seen with mean monocyte volume (MMoV). Neutrophil and monocyte conductivity and scatter parameters were variably associated. The AUC was highest for MMoV (0.74) and lowest for CRP (0.62). Among all parameters, MNV and MMoV had the highest specificity of 85% and 80%, respectively.

CONCLUSION:

In critically ill patients with suspected sepsis, VCS parameters may help strengthen the diagnostic probability of sepsis. Future studies may explore the role of serial monitoring of VCS to track response to antimicrobial therapy.

Utility of cell population data (VCS parameters) as a rapid screening tool for Acute Myeloid Leukemia (AML) in resource-constrained laboratories

INTRODUCTION

Despite advances in diagnostic techniques, many cases of acute myeloid leukemia (AML) remain underdiagnosed in remote centers unequipped with these technologies. We hypothesized that the automated cellular indices with scatter plots and flags may aid in rapid and cost-effective screening of AML.

METHODS

Cell population data (CPD) parameters from 100 de novo AML samples were analyzed by Coulter LH 780 automated analyzer and were compared with 100 age-matched controls. Similar parameters were also compared with 100 and 50 reactive cases of neutrophilia and monocytosis, respectively. System-generated flags and scatter plot patterns were also analyzed.

RESULTS

Results were compared between AML cases and normal controls; AML FAB M2, M3, M4 vs reactive neutrophilia; AML FAB M4, M5 vs reactive monocytosis. Significant parameters were selected from all comparison groups. Using appropriate statistical tools, we calculated the cutoff values of these parameters and were able to screen out AML cases with 94% sensitivity and 95% specificity. Three statistical equations were generated using two of the most significant parameters which improved the sensitivity to 98% and specificity to 99%. Five hypothetical scatter plot patterns were devised and were classified according to FAB categories of AML. Most common pattern was selected in AML which was seen in 56% of the cases. Output was analyzed combining these patterns and flags with CPD parameters.

CONCLUSION

CPD either alone or in the form of statistical equations along with scatter plots and flags can provide rapid and economic tool in preliminary diagnosis of AML in cost-constrained settings.

Detection of sepsis in patient blood samples using CD64 expression in a microfluidic cell separation device

A microfluidic affinity separation device was developed for the detection of sepsis in critical care patients.

Quantitative and volume, conductivity and scatter changes in leucocytes of patients with acute undifferentiated febrile illness: a pilot study

BACKGROUND

A single diagnostic test for acute undifferentiated febrile illnesses (AUFI) is elusive. This pilot study was undertaken on the premise that leucocytes, being the main cells of defence, undergo quantitative, structural and functional changes in AUFI. We evaluated the potential of volume, conductivity and scatter (VCS) parameters of leucocytes, generated with the haemogram report by the Coulter auto-analyzer, in differentiating the common etiologies of AUFI.

METHODS

The haematological and VCS data obtained from 800 controls and 200 cases of AUFI (50 cases each of acute malaria, dengue, scrub typhus and enteric fever) were retrieved for analysis.

RESULTS

The cases and controls differed significantly with respect to relative numbers and the VCS parameters of neutrophils, lymphocytes and monocytes (p<0.05). The neutrophil and lymphocyte were significantly voluminous in acute malaria and scrub typhus as compared to dengue and enteric fevers (p<0.05). Enteric fever significantly enhanced the conductivity of neutrophils as compared to other subgroups while lymphocyte conductivity significantly differed from dengue and scrub typhus. Lymphocyte and neutrophil scatter values in malaria and scrub typhus were comparable but differed significantly from that in enteric fever.

CONCLUSIONS

Etiology-specific changes occur in leucocytes, both in numbers and their VCS properties which can be identified without additional cost.

The Importance of Mean Neutrophil Volume (MNV) Values in Differential Diagnosis of Bacterial Sepsis

INTRODUCTION

Bloodstream infections are a significant cause of morbidity and mortality in hospitalized patients. Blood cultures and other laboratory tests are used for diagnosis. Among these tests, the mean neutrophil volume (MNV) value is reported as a potential indicator that supports the diagnosis of sepsis. Our study identified the MNV values of patients via microorganisms cultivated from blood cultures and examined the role of these MNV values in the early diagnosis of bloodstream infections.

METHODS

Our study surveyed retrospectively 148 adult patient blood culture samples that had been sent to our laboratory. BACTEC 9050 (Becton Dickinson, USA) and BACTEC FX 40 (Becton Dickinson, USA) devices were used in the blood culture isolation procedures.

RESULTS

The average MNV value was found to be 159.0 (+11.3) in patients whose sepsis originated from Gram-negative bacteria, and the average MNV value was measured as 152.4 (+14.5) among patients whose sepsis originated from Gram-positive bacteria. When comparing groups of patients having Gram-negative bacteria and patients having Gram-positive bacteria, a statistically significant difference (p = 0.041) in the MNV values was observed.

CONCLUSION

The MNV value was found to be statistically significant in discrimination of Gram-negative and Gram-positive sepsis. Considering these findings, measuring the MNV values can help initiate proper antibiotic treatment more quickly, and we think that this will help lower the mortality rate. However, these findings should be supported with further studies.

Improved Early Detection of Sepsis in the ED With a Novel Monocyte Distribution Width Biomarker

BACKGROUND

Sepsis most often presents to the ED, and delayed detection is harmful. WBC count is often used to detect sepsis, but changes in WBC count size also correspond to sepsis. We sought to determine if volume increases of circulating immune cells add value to the WBC count for early sepsis detection in the ED.

METHODS

A blinded, prospective cohort study was conducted in two different ED populations within a large academic hospital.

RESULTS

Neutrophil and monocyte volume parameters were measured in conjunction with routine CBC testing on a UniCel DxH 800 analyzer at the time of ED admission and were evaluated for the detection of sepsis. There were 1,320 subjects in the ED consecutively enrolled and categorized as control subjects (n = 879) and those with systemic inflammatory response syndrome (SIRS) (n = 203), infection (n = 140), or sepsis (n = 98). Compared with other parameters, monocyte distribution width (MDW) best discriminated sepsis from all other conditions (area under the curve [AUC], 0.79; 95% CI, 0.73-0.84; sensitivity, 0.77; specificity, 0.73; MDW threshold, 20.50), sepsis from SIRS (AUC, 0.74; 95% CI, 0.67-0.84), and severe sepsis from noninfected patients in the ED (AUC, 0.88; 95% CI, 0.75-0.99; negative predictive value, 99%). The added value of MDW to WBC count was statistically significant (AUC, 0.89 for MDW + WBC vs 0.81 for WBC alone; P < .01); a decision curve analysis also showed improved performance compared with WBC count alone.

CONCLUSIONS

The incorporation of MDW with WBC count is shown in this prospective cohort study to improve detection of sepsis compared with WBC count alone at the time of admission in the ED.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT02232750; URL: www.clinicaltrials.gov.

Utility of neutrophil volume conductivity scatter (VCS) parameter changes as sepsis screen in neonates

OBJECTIVE

The objective of this study was to determine changes in neutrophil volume conductivity scatter (VCS) parameters and their distribution widths (DW) in neonatal sepsis and to estimate their optimal cutoff levels using receiver operating characteristic (ROC) curves.

STUDY DESIGN

In a cohort of neonates evaluated for sepsis, blood counts and blood culture were performed initially, with repeat counts and C-reactive protein (CRP) done after 24 to 48 h. Neutrophil VCS parameters from both the initial and repeat blood counts were analyzed. Babies were classified as having blood culture-positive sepsis, probable sepsis (clinical course consistent with sepsis and CRP-positive, but culture-negative) and no sepsis (clinical course not compatible with sepsis, culture- and CRP-negative).

RESULTS

A total of 600 babies were included: 240 (40%) babies in the sepsis group and 360 (60%) babies in the control group. All the neutrophil VCS parameters and their DWs (except for low angle light scatter in the repeat counts) were significantly different between the two groups, with an area under curve in the ROC curve of >0.6 for most parameters. The five most significant VCS parameters (mean neutrophil volume (MNV), median angle light scatter (MALS), lower median angle light scatter (LMALS), MNV-DW and ALL-DW) had around 65 to 75% sensitivity and specificity. A combination of leukopenia, thrombocytopenia, MNV and LMALS had a likelihood ratio (LR)+ of 15.3 and LR- of 0.17. With a pre-test probability of 40%, post-test probability increased to 91% for a positive test and decreased to 10% for a negative test. A prospective validation study was performed recruiting an additional 60 babies, which showed similar results, assuring that the cutoffs were robust.

CONCLUSION

Neutrophil VCS parameters cannot be considered as stand-alone tests to diagnose or rule out neonatal sepsis, but can be used in combination with other hematological screening tests to improve the diagnostic accuracy of the neonatal sepsis screen.

Efficacy of new leukocyte parameters versus serum C-reactive protein, procalcitonin, and interleukin-6 in the diagnosis of neonatal sepsis

BACKGROUND

The aim of this study was to investigate and compare the efficacy of the new leukocyte parameters mean neutrophil and monocyte volume (MNV, MMV), conductivity (MNC, MMC), scattering (MNS, MMS) and volume distribution width (NDW, MDW) with serum C-reactive protein (CRP), procalcitonin (PC) and interleukin (IL)-6 in the diagnosis of neonatal sepsis.

METHODS

A total of 227 newborns (132 boys, 95 girls) were analyzed. There were 116 infants in the sepsis group (proven sepsis, n = 40; clinical sepsis, n = 76) and 111 in the control group. Venous blood samples were collected from infants at the time of diagnosis and complete blood count, peripheral blood smear, blood cultures, CRP, PC, IL-6 and MNV, MMV, MNC, MMC, MNS, MMS, NDW, and MDW were analyzed.

RESULTS

MNV, NDW, MMV and, MDW were higher in infants with sepsis than in controls (P < 0.05 for all). MNS was lower in the patients with sepsis (P = 0.002). There was no significant difference between the sepsis and control groups in terms of MNC, MMC and MMS.

CONCLUSION

Although the predictive value of leukocyte parameters including neutrophil and monocyte volume, conductivity, scattering and volume distribution width in the diagnosis of neonatal sepsis was lower than that of CRP, PC and IL-6, some of these new parameters may be useful in the differential diagnosis of newborn sepsis, along with the other screening tools. In particular, MNV seems to be the most useful parameter with the highest specificity; also, the importance of PC in the diagnosis of early onset sepsis was confirmed.

Volume Conductivity and Scatter Parameters as an Indicator of Acute Bacterial Infections by the Automated Haematology Analyser

INTRODUCTION

Complete blood picture is the first and foremost investigation ordered for evaluation of acute infectious processes which require early and prompt intervention. With the advent of automated Coulter (®) Haematology analysers, the Volume, Conductivity & Scatter parameters of the leucocytes could be analysed for the early detection of the infections.

AIM

To evaluate the clinical usefulness of Volume, Conductivity & Scatter parameters of neutrophils & monocytes in predicting the onset of acute bacterial infections.

MATERIALS AND METHODS

Peripheral blood samples from 94 patients with infections (systemic infections n=36 & localised infections n=58) and 46 control subjects were studied using the Volume, Conductivity & Scatter parameters by the Coulter Haematology analyser.

RESULTS

We observed a significant increase in the mean channel of neutrophil volume & mean channel of monocyte volume from patients with infections (both systemic & localised) as compared with control subjects (Mean Neutrophil Volume: 158.3 ± 13.7 vs 137.2 ± 4.3; p<0.001) & (Mean Monocyte Volume: 177.8± 16 vs 161.7 ± 6.04; p <0.001). However, there was no significant difference in the Mean Neutrophil Volume of patients with systemic infection & localised infections (160.5±17.5 vs 156.8±10.5, p>0.05).

CONCLUSION

The Volume, Conductivity & Scatter parameters like Mean Neutrophil Volume & Mean Monocyte Volume are more sensitive parameters and could prove to be a quick diagnostic indicator of acute bacterial infections.

Elevated mean neutrophil volume represents altered neutrophil composition and reflects damage after myocardial infarction

Myocardial infarction (MI) induces an inflammatory response in which neutrophils fulfill a prominent role. Mean neutrophil volume (MNV) represents the average size of the circulating neutrophil population. Our goal was to determine the effect of MI on MNV and investigate the mechanisms behind MNV elevation. MNV of 84 MI patients was compared with the MNV of 209 stable angina patients and correlated to simultaneously measured CK levels. Fourteen pigs were subjected to temporary coronary balloon occlusion and blood was sampled at multiple time points to measure MNV. Echocardiography was performed followed by ex vivo infarct size assessment after 72 h. MNV was higher in MI patients compared to stable angina patients (602 SD26 AU vs. 580 SD20 AU, p < 0.0001) and correlated with simultaneously measured CK levels (R = 0.357, p < 0.0001). In pigs, MNV was elevated post-MI (451 SD11 AU vs. 469 SD12 AU), p < 0.0001). MNV correlated with infarct size (R = 0.705, p = 0.007) and inversely correlated with left ventricular ejection fraction (R = −0.718, p = 0.009). Cell sorting revealed an increased presence of banded neutrophils after MI, which have a higher MNV compared to mature neutrophils post-MI (495 SD14 AU vs. 478 SD11 AU, p = 0.012). MNV from coronary sinus blood was higher than MNV of neutrophils from simultaneously sampled arterial blood (463 SD7.6 AU vs. 461 SD8.6 AU, p = 0.013) post-MI. The current study shows MNV is elevated and reflects cardiac damage post-MI. MNV increases due to altered neutrophil composition and systemic neutrophil activation. MNV may be an interesting parameter for prognostic assessment in MI and provide new insights into pathological innate immune responses evoked by ischemia–reperfusion.

Cell population data in neonates: differences by age group and associations with perinatal factors

INTRODUCTION

Cell population data (CPD) describe physical parameters of white blood cell subpopulations and are reported to be of some value in the diagnosis of sepsis in neonates. Before using the CPD for diagnosing sepsis, the baseline features of the CPD distribution in healthy neonates should be clarified. The aim of this study was to compare the CPD distributions of healthy neonates and other age groups and to identify perinatal factors that are associated with changes in the CPD distribution of healthy neonates.

METHODS

The CPD distribution of 69 samples from term neonates was compared with adolescents and adults. The CPD distribution of 163 samples from healthy neonates was analyzed in association with perinatal factors, including gestational age, chronologic age, birthweight, delivery mode, premature rupture of membranes, diabetes, and pregnancy-induced hypertension.

RESULTS

The CPD distribution for term neonates was significantly different from those in adolescents and adults. The mean lymphocyte volume showed a negative correlation with gestational age at birth (r = -0.305; P < 0.01). The mean neutrophil volume was smaller in the cesarean section group than in the normal delivery group. The small for gestational age (SGA) group had smaller mean neutrophil volume and mean monocyte volume than the appropriate for gestational age group.

CONCLUSION

The CPD distribution of healthy neonates differed from those of adolescents or adults, and the differences were associated with gestational age, delivery mode, and being SGA.

Automated screening for myelodysplastic syndromes through analysis of complete blood count and cell population data parameters

The diagnosis of myelodysplastic syndromes (MDS) requires a high clinical index of suspicion to prompt bone marrow studies as well as subjective assessment of dysplastic morphology. We sought to determine if data collected by automated hematology analyzers during complete blood count (CBC) analysis might help to identify MDS in a routine clinical setting. We collected CBC parameters (including those for research use only and cell population data) and demographic information in a large (>5,000), unselected sequential cohort of outpatients. The cohort was divided into independent training and test groups to develop and validate a random forest classifier that identifies MDS. The classifier effectively identified MDS and had a receiver operating characteristic area under the curve (AUC) of 0.942. Platelet distribution width and the standard deviation of red blood cell distribution width were the most discriminating variables within the classifier. Additionally, a similar classifier was validated with an additional, independent set of >200 patients from a second institution with an AUC of 0.93. This retrospective study demonstrates the feasibility of identifying MDS in an unselected outpatient population using data routinely collected during CBC analysis with a classifier that has been validated using two independent data sets from different institutions.

Delta mean neutrophil volume (ΔMNV) is comparable to procalcitonin for predicting postsurgical bacterial infection

BACKGROUND

The Coulter LH750 (Beckman Coulter, Brea, CA) analyzer can determine intrinsic biophysical properties of white blood cell (WBC), known as cell population data. Previous studies have shown that mean neutrophil volume (MNV) was significantly increased in postsurgical patients with bacterial infection. To further validate its potential clinical usefulness, we investigate the changes in MNV before and after surgery, called ΔMNV. We also compare the ΔMNV with procalcitonin (PCT) and C-reactive protein (CRP) in terms of diagnostic sensitivity and specificity for postsurgical bacterial infection.

METHODS

Blood samples from 300 healthy controls, 219 cardiac surgical patients without postsurgical infection, and 31 cardiac surgical patients complicated with postsurgical bacterial infection were studied.

RESULTS

There are no statistically significant differences for WBC count and neutrophil percentage prior to or after surgery between postsurgical noninfected and infected patients. However, the ΔMNV is significantly increased in postsurgical infected patients when compared with noninfected patients (P < 0.05). The receiver-operating characteristics analysis reveals the ΔMNV and PCT have largest areas under curves (0.92, 0.93 on the second day and 0.94, 0.99 on the third day postsurgery, respectively) compared to other parameters.

CONCLUSION

ΔMNV shows comparable sensitivity and specificity to PCT and superior sensitivity and specificity to WBC or CRP for predicting postsurgical bacterial infection. The potential clinical application of this parameter merits further exploration in a larger prospective study.