Prognostic value of platelet-to-lymphocyte ratio in neoadjuvant chemotherapy for solid tumors: A PRISMA-compliant meta-analysis.

INTRODUCTION: Previous research indicates that the platelet-to-lymphocyte ratio (PLR) may be an indicator of poor prognosis in many tumor types. However, the PLR is rarely described in patients undergoing neoadjuvant chemotherapy (NAC) for solid tumors. Thus, we performed a meta-analysis to investigate the prognostic value of this ratio for patients with solid tumors treated by NAC. METHODS: A comprehensive search of the literature was conducted using the PubMed, EMBASE, Cochrane Library, and Web of Science databases, followed by a manual search of references from the retrieved articles. Pooled hazard ratios (HRs) with 95% confidence interval (CIs) were used to evaluate the association between PLR and 3 outcomes, namely, overall survival, disease-free survival, and pathological complete response rate after NAC. RESULTS: Eighteen studies published no earlier than 2014 were included in our study. A lower PLR was associated with better overall survival (HR = 1.46, 95% CI, 1.11-1.92) and favorable disease-free survival (HR = 1.81, 95% CI, 1.27-2.59). A PLR that was higher than a certain cutoff was associated with a lower pathological complete response rate in patients with cancer who received NAC (Odds ratio = 1.93, 95% CI, 1.40-2.87). CONCLUSION: Elevated PLR is associated with poor prognosis in various solid tumors. PLR may be a useful biomarker in delineating those patients with poorer prognoses who may benefit from neoadjuvant therapies.

Alinity hq platelet results are equivalent with the international reference method in thrombocytopenic samples.

INTRODUCTION: Accurate and precise platelet (PLT) count is critical for the appropriate management of patients with thrombocytopenia. This study evaluated the performance of PLT counting with the Abbott Alinity hq hematology analyzer, which utilizes multi-dimensional optical technology. METHODS: Imprecision, linearity, and accuracy were assessed per CLSI guidelines. Alinity hq PLT results were compared to the international flow cytometry reference method (IRM) in the concentration range of 6.3 to 103.0 × 109 /L. Additional comparisons were made with Sysmex XN-3000 PLT counts: impedance (PLT-I), optical (PLT-O), and optical fluorescent (PLT-F) methods. RESULTS: The average within-run %CV was 4.7% on patient samples with PLT concentrations ranging from 13.1 to 41.7 × 109 /L, and the within-laboratory %CV was 3.6% at the level of 68.2 × 109 /L. Linearity evaluation indicated a maximum deviation of 3.1% from the linear fit in the range of 0.1 to 316.8 × 109 /L. Comparison between Alinity hq and the IRM PLT counts yielded a correlation coefficient of 0.99 and predicted bias of 0.0 and -0.5 × 109 /L at 10.0 and 20.0 × 109 /L transfusion thresholds, respectively. Alinity hq PLT counts also correlated well with Sysmex PLT counts, with strongest correlation obtained with PLT-F and PLT-O (r = .99) methods. CONCLUSION: This study demonstrated excellent analytical performance of Alinity hq PLT counting in thrombocytopenic samples, equivalency with the IRM and strong agreement with Sysmex PLT-F and PLT-O methods. The Alinity hq multi-dimensional optical PLT count is available with every CBC without additional reagents and may help promote efficiency in clinical laboratories.

Establishing local reference intervals for full blood count and white blood cell differential counts in Cape Town, South Africa.

BACKGROUND: Accurate laboratory reference intervals (RIs) are essential to differentiate between health and disease. There are variations in haematological indices within populations relating to gender, age, ethnicity and environment. Iron deficiency is common, has a wide range of clinical morbidities and affects red cell indices. Locally derived RIs for full blood count (FBC) parameters are needed for the Western Cape region of South Africa, after the exclusion of iron deficiency. In addition, information regarding the prevalence of iron deficiency in first-time blood donors would inform blood transfusion services regarding policies to screen for and treat iron deficiency. OBJECTIVES: To establish locally derived RIs for FBC and white blood cell (WBC) differential count parameters in healthy adults in the Cape Town area, by including first-time blood donors and excluding those with iron deficiency and thalassaemic indices. These new locally established RIs could update those in use by the local National Health Laboratory Service. A secondary objective was to establish the prevalence of iron deficiency in first-time blood donors. This would inform blood donation policies regarding screening and appropriate iron supplementation in high-risk groups prior to blood donation. METHODS: This was a prospective, descriptive study with direct convenience sampling. Participants were prospective voluntary blood donors aged between 18 and 60 years, presenting for first-time blood donation. Ethnicity was self-identified. Participants who tested positive for HIV or hepatitis B and/or C viruses were excluded. Prospective participants with iron deficiency, defined by serum ferritin levels below the RI, and those with red cell indices suggestive of an underlying thalassaemia trait were excluded. FBC samples were analysed using a Sysmex XN-1000 cell counter. Statistical non-parametric methods were used to calculate the RIs, according to international guidelines. RESULTS: Of the 774 participants screened, 82 (11%) had iron deficiency and were excluded. Six hundred and sixty-two patients were included for analysis, 409 (62%) female and 253 (38%) male. The majority of the participants, 348 (53%), were between 20 and 29 years of age, with a mean age of 29 years for females and 28 years for males. Participants comprised a mix of the various ethnic groups residing in Western Cape Province. The mean haemoglobin concentration for females was lower than that for males (p<0.0001). There were significant gender differences for total WBC count, absolute neutrophil count and platelet count, with females having higher counts than males. CONCLUSIONS: Locally established, population-specific RIs are essential for the accurate interpretation of haematological indices. This study established locally derived gender-specific RIs for the Cape Town region, after exclusion of iron deficiency. These new RIs have implications for the accurate diagnoses of cytopenias, cytoses and other blood count abnormalities. Iron deficiency is common in first-time blood donors, and screening for iron deficiency using point-of-care testing should be considered.

Clinical and Prognostic Features of Essential Thrombocythemia: Comparison of 2001 WHO Versus 2008/2016 WHO Criteria in a Large Single-center Cohort.

BACKGROUND: According to 2008/2016 classification of the World Health Organization (WHO), a platelet (PLT) count ≥ 450 × 109/L, reduced from the previously published WHO 2001 indicated level ≥ 600 × 109/L, was considered the new PLT threshold for the diagnosis of essential thrombocythemia (ET). PATIENTS AND METHODS: To validate this important diagnostic change in a setting of current clinical practice, we retrospectively analyzed clinical and hematologic features at diagnosis and during follow-up of 162 patients with ET, diagnosed in our center from January 2008 to December 2017. We subdivided patients according to PLT value at baseline into Group A (PLT ≥ 600 × 109/L) (124 patients; 76.5%) and Group B (PLT ≥ 450 × 109/L < 600 × 109/L) (38 patients; 23.5%). RESULTS: Among clinical features, only the median value of leukocytes (P < .001) was significantly higher in Group A. Cytostatic treatment was administered in 103 patients, with a significantly higher rate in patients of group A (P < .001). After a median follow-up of 42.4 months (interquartile range, 22.1-70.6 months), 8 thrombotic events were recorded in the entire cohort, without differences between the 2 groups (P = .336). The 5-year overall survival (OS) of the entire cohort was 96.9% (95% confidence interval, 92.6%-100%), without differences between the 2 groups (P = .255). CONCLUSIONS: Our data indicate a substantial homogeneity among patients with ET regardless of the PLT count at diagnosis, thus confirming the usefulness of the 2008/2016 WHO diagnostic criteria.

Non-invasive fibrosis algorithms are clinically useful for excluding cirrhosis in prisoners living with hepatitis C.

BACKGROUND AND AIMS: Prison-based HCV treatment rates remain low due to multiple barriers, including accessing transient elastography for cirrhosis determination. The AST-to-platelet ratio index (APRI) and FIB-4 scores have excellent negative predictive value (NPV) in hospital cohorts to exclude cirrhosis. We investigated their performance in a large cohort of prisoners with HCV infection. METHODS: This was a retrospective cohort study of participants assessed by a prison-based hepatitis program. The sensitivity, specificity, NPV and positive predictive value (PPV) of APRI and FIB-4 for cirrhosis were then analysed, with transient elastography as the reference standard. The utility of age thresholds as a trigger for transient elastography was also explored. RESULTS: Data from 1007 prisoners were included. The median age was 41, 89% were male, and 12% had cirrhosis. An APRI cut-off of 1.0 and FIB-4 cut-off of 1.45 had NPVs for cirrhosis of 96.1% and 96.6%, respectively, and if used to triage prisoners for transient elastography, could reduce the need for this investigation by 71%. The PPVs of APRI and FIB-4 for cirrhosis at these cut-offs were low. Age ≤35 years alone had a NPV for cirrhosis of 96.5%. In those >35 years, the APRI cut-off of 1.0 alone had a high NPV >95%. CONCLUSION: APRI and FIB-4 scores can reliably exclude cirrhosis in prisoners and reduce requirement for transient elastography. This finding will simplify the cascade of care for prisoners living with hepatitis C.

[Usefulness of immature platelet fraction measurement for diagnosis and monitoring of iron deficiency associated thrombocytopenia: about two cases]. / Apport de la mesure de la fraction de plaquettes immatures dans le diagnostic et le suivi des thrombopénies ferriprives : à propos de deux cas.

Iron deficiency anemia is frequently associated with thrombocytosis. However, in some rare cases of very severe iron deficiency, a thrombocytopenia may occur. This condition may lead to a misdiagnosis of immune thrombocytopenic purpura and thus to unnecessary tests in this context. Here we report two patients who presented with iron deficiency associated thrombocytopenia rapidly corrected after martial supplementation. We then discuss the value of measuring immature platelet fraction (IPF), which represents the population of newly formed platelets containing a greater amount of residual RNA. For both cases, low IPF values at admission indicated a central origin of thrombocytopenia with decreased platelet production, which is the pathophysiological mechanism of iron deficiency associated thrombocytopenia.

Multicenter evaluation of analytical performances of platelet counts and platelet parameters: Carryover, precision, and stability.

INTRODUCTION: The correctness of the results of automated platelet analysis is still highly debated. The aim of this multicenter study, conducted according to international guidelines, was to verify the analytical performance of nine different types of hematology analyzers (HAs) in the automated platelet analysis. METHODS: Four hundred eighty-six peripheral blood samples (PB), collected in K3 EDTA tubes, were analyzed by ABX Pentra, ADVIA2120i, BC-6800, BC-6800 Plus, Cell-DYN Sapphire, DxH800, XE-2100, XE-5000, XN-20 with PLT-F App. Within-run imprecision and between-run imprecision were carried out using PB and material control, respectively. The carryover, low limit of quantification (LoQ), and the PB stability were evaluated. RESULTS: The carryover was absent for all HAs. The LoQ of PLT ranged between 2.0 (Cell-Dyn Sapphire) and 25.0 × 109 /L (ADVIA 2120i), while immature platelet fraction (IPF) ranged between 1.0 (XN-20) and 12.0 × 109 /L (XE-5000). The imprecision (%CV) increases as the platelet count decreases. No HAs showed desirable CVAPS for PLT counts less than 50.0 × 109 /L, with the exception of Cell-DYN Sapphire (CV 3.0% with PLT-O mean value of 26.7 × 109 /L), XN-20 (CV 2.4% with PLT-F mean value of 21.5 × 109 /L), and BC-6800 Plus (CV 1.9% with PLT-O mean value of 26.5 × 109 /L). The sample stability ranged between under two hours for MPV by ADVIA2120i and 8 hours for other PLT parameters and HAs. CONCLUSION: The findings of this study may provide useful information regarding carryover, precision, and stability of platelet counts and parameters, especially in thrombocytopenic samples. Moreover, the stability of sample for platelet analysis is conditioned by the HA and by temperature and storage time.

Quality of blood samples collected at home does not affect clinical decision making for the administration of systemic cancer treatment.

The aim of this exploratory clinical study was to evaluate whether the preanalytical quality of blood samples subjected to delayed centrifugation and transport - as a result of home-sampling - is affected in a way it alters the clinical decision-making for patients under systemic cancer therapy. This evaluation is part of a comprehensive investigation of the opportunities for oncological home-hospitalization. Forty-nine patients with cancer donated two additional blood samples during their ambulatory hospital visit. Fifteen blood analytes were compared between routine blood samples and samples that were subjected to transport and delayed centrifugation in order to mimic a locally implemented model for oncological home-hospitalisation. Deviations were analysed by means of Deming regression. For those analytes showing statistically significant intercepts and/or slopes, the mean deviations were compared to the desirable analytical bias; and the intra-individual differences were compared with the limits for clinical decision-making. Statistically significant intercepts and/or slopes were observed for haematocrit (HCT), mean cellular volume (MCV), platelets count (PLT) and C-reactive protein (CRP). Differences exceeding the allowable margins of desirable analytical bias were observed for HCT and MCV. Risk of different clinical decision-making couldn't be observed for any of the analytes showing statistically significant differences. These results demonstrate that home-collection of blood samples, transported at room temperature and centrifuged within a mean time of five hours after sampling, has no effect on clinical decision-making with regards to systemic cancer therapy. However, attention should be paid to the potential occurrence of haemolysis during the preanalytical phase, which can negatively influence haemolysis-dependent variables.

[Clinical laboratory criteria and its utility as predictive of diagnosis of the cardiopulmonary syndrome by hantavirus]. / Criterios de laboratorio clínico y su utilidad como predictores del diagnóstico de síndrome cardiopulmonar por hantavirus.

BACKGROUND: The hantavirus infection is an emerging zoonotic disease, endemic in Chile, generating the hantavirus cardiopulmonary syndrome (HCPS), characterized by cardiopulmonary dysfunction with rapidly progressive respiratory failure and high lethality. For an early clinical orientation of HCPS, due to its non-specificity in symptoms and to help the differential diagnosis, some laboratory parameter that may be useful have been studied. AIM: To identify laboratory criteria as predictive factors of HCPS in patients with suspected hantavirus infection. METHODOLOGY: Retrospective cohort study of 71 patients admitted to the Hospital Guillermo Grant Benavente Emergency. We determined discriminative capacity of laboratory's parameters at the time of admission: platelets recount, hematocrit, inmunoblasts, activated partial thromboplastin time (aPTT) and aspartate aminotransferase (AST/GOT). RESULTS: Were found significant differences in all parameters studied between confirmed patients (22) with respect to unconfirmed (49). Hematocrit, inmunoblasts, AST/GOT and aPTT had a OR > 1 and platelets count had a OR < 1. The best combination for predict HCPS was hematocrit, platelets count and AST/GOT with 90,01% sensibility and 81,63% specificity. CONCLUSION: The five parameters studied are good predictors of HCS in suspicious patients and they would may be useful in low complexity hospitals for quick transfer a center with critical care units.

Full blood count and white cell differential count reference ranges obtained from a healthy urban South African population residing in the Western Cape of South Africa.

BACKGROUND: Research has suggested that individuals of African descent have lower white cell and neutrophil counts than Caucasians. These differences could lead to incorrect clinical decisions, and therefore, ethnic-specific reference ranges are required. The Western Cape region of South Africa is uniquely diverse, comprising Caucasian, Mixed Ancestry and those of African descent. The aim of this study was to compare the full blood count and differential counts across the three major ethnic groups residing in this area and to propose appropriate RIs. METHODS: The study formed part of the international project led by the Committee on Reference Intervals and Decision Limits (C-RIDL), and therefore, the strict guidelines laid out by the committee were followed. Full blood count and differential counts were performed on a Beckman Coulter ACT 5 diff AL analyser within 2-4 hours of collection and were reported as mean (standard deviation), 2.5th and 97.5th percentiles. Comparisons were analysed using Spss v25 and Statistica v13, and a P value of < 0.05 was considered significant. RESULTS: Reference ranges for Caucasian and Mixed Ancestry individuals were similar while white cell (P = 0.016), monocyte (P < 0.001), neutrophil (P = 0.034) and red cell indices were significantly different amongst the three population groups. There were however no statistical and clinical significant differences between the eosinophil, lymphocyte, red cell and platelet counts across the three groups. CONCLUSION: In conclusion, subjects of Mixed Ancestry, in this region, have similar reference intervals to those of European descent, while lower white cell and neutrophil counts in Africans have been confirmed.

Criterios de laboratorio clínico y su utilidad como predictores del diagnóstico de síndrome cardiopulmonar por hantavirus / Clinical laboratory criteria and its utility as predictive of diagnosis of the cardiopulmonary syndrome by hantavirus

Resumen Introducción: La infección por hantavirus es una zoonosis emergente, endémica en Chile, generando el síndrome cardiopulmonar por hantavirus (SCPH), caracterizado por disfunción cardiopulmonar con falla respiratoria rápidamente progresiva y altamente letal. Para una orientación clínica precoz del SCPH, debido a su poca especificidad en síntomas y ayudar al diagnóstico diferencial, se han estudiado algunos parámetros de laboratorio que puedan ser de utilidad. Objetivo: Identificar criterios del laboratorio como factores predictores del diagnóstico de SCPH en pacientes con sospecha de enfermedad por hantavirus. Metodología. Estudio de cohorte retrospectiva de 71 pacientes que ingresaron a Urgencia del Hospital Guillermo Grant Benavente. Se determinó la capacidad discriminativa de parámetros de laboratorio al momento de ingreso: recuento de plaquetas, hematocrito, inmunoblastos, TTPa y GOT. Resultados: Se encontraron diferencias significativas en los parámetros estudiados entre pacientes confirmados (n: 22) con respecto a los no confirmados (n: 49). Hematocrito, inmunoblastos, GOT y TTPa tuvieron un OR > 1 y las plaquetas un OR < 1. La mejor combinación para predecir SCPH fue hematocrito, plaquetas y GOT con sensibilidad 90,9% y especificidad 81,6%. Conclusión: Los cinco parámetros estudiados son buenos predictores de SCPH en pacientes con sospecha del mismo y podrían ser útiles en hospitales de baja complejidad para rápido traslado a centro que cuente con unidad de pacientes crítico.

Background. The hantavirus infection is an emerging zoonotic disease, endemic in Chile, generating the hantavirus cardiopulmonary syndrome (HCPS), characterized by cardiopulmonary dysfunction with rapidly progressive respiratory failure and high lethality. For an early clinical orientation of HCPS, due to its non-specificity in symptoms and to help the differential diagnosis, some laboratory parameter that may be useful have been studied. Aim: To identify laboratory criteria as predictive factors of HCPS in patients with suspected hantavirus infection. Methodology: Retrospective cohort study of 71 patients admitted to the Hospital Guillermo Grant Benavente Emergency. We determined discriminative capacity of laboratory's parameters at the time of admission: platelets recount, hematocrit, inmunoblasts, activated partial thromboplastin time (aPTT) and aspartate aminotransferase (AST/GOT). Results: Were found significant differences in all parameters studied between confirmed patients (22) with respect to unconfirmed (49). Hematocrit, inmunoblasts, AST/GOT and aPTT had a OR > 1 and platelets count had a OR < 1. The best combination for predict HCPS was hematocrit, platelets count and AST/GOT with 90,01% sensibility and 81,63% specificity. Conclusion: The five parameters studied are good predictors of HCS in suspicious patients and they would may be useful in low complexity hospitals for quick transfer a center with critical care units.

Compare the accuracy and precision of Coulter LH780, Mindray BC-6000 Plus, and Sysmex XN-9000 with the international reference flow cytometric method in platelet counting.

OBJECTIVE: The aim of this study is to evaluate the performance of different platelet counting methods (optical, impedance, fluorescence and hand counting) applied in different analysers by comparing with the international flow cytometric reference method (IRM). METHODS: A total of 333 blood samples from different subgroups (168 cases with thrombocytopenia, 136 cases with normal platelet counts and 29 cases with thrombocytosis) were tested. Regarding IRM as the gold standard, we compared the accuracy and precision of different platelet count methods; i.e. LH780 (impedance), BC-6000 Plus (optical (O) and impedance (I)), Sysmex XN-9000 (optical (O), impedance (I), fluorescence (F)), and hand counting. RESULTS: Sysmex XN-9000-F (r = 0.988) had the best correlation with IRM for thrombocytopenic samples; BC-6000 Plus-I (r = 0.966) was more relevant to IRM than any other method for samples with normal platelet counts. Correlation between Sysmex XN-9000-I (r = 0.960) and IRM was the highest among these methods for samples with thrombocytosis. For bias evaluation, the average bias of Sysmex XN-9000-F was -1.5 × 109/L (95% LA = -9.4 to +6.4) for samples with thrombocytopenia, compared with IRM. BC-6000 Plus-I had a small mean difference with IRM for samples with normal platelet counts or thrombocytosis. Moreover, all evaluated methods had acceptable sensitivity, specificity, and concordance rates as compared with IRM in the diagnosis of thrombocytopenia and thrombocytosis. CONCLUSIONS: Platelet counting by Sysmex XN-9000-F is more accurate than other methods for thrombocytopenic samples. BC-6000 Plus-I has superior association and consistency for normal platelet counts. As for thrombocytosis patients, Sysmex XN-9000-I has the highest correlation with IRM while Sysmex XN-9000-O has the highest diagnosis efficacy.

Establishing a reference range for thromboelastograph parameters in the neonatal period.

INTRODUCTION: Acquired coagulation disorders are a common cause of neonatal bleeding. The thromboelastograph (TEG) comprehensively assesses haemostatic processes in the body. Unfortunately, the reference range of TEG parameters in the neonatal period has not yet been evaluated, which limits the use of the TEG in neonates. In this study, we aimed to establish the reference range of TEG parameters for the neonatal period. METHODS: This study included 371 full-term infants (≥37 weeks of gestation), and we divided these infants into three groups according to age as follows: 1, 2-7 and 8-28 days. We measured their peripheral blood using TEG, coagulation routine and platelet count tests. We analysed differences among the groups. RESULTS: The reference ranges for TEG parameters are presented as medians and reference ranges (2.5th and 97.5th percentiles) as follows: R (clot reaction time, seconds) 4.80 (2.80-7.17), Angle (fibrin production rate) 69.90 (44.91-78.89), K (clot kinetics, min) 1.40 (0.80-4.50), MA (maximum amplitude, mm) 63.50(44.34-74.66) and LY30 (lysis at 30 minutes, %) 0.10 (0.10-6.95). There were significant differences in Angle, K, MA and LY30 values between the different neonatal day age groups. CONCLUSION: This study preliminarily establishes a reference range for TEG parameters during the neonatal period. The age of a newborn had a large influence on TEG parameters. Additionally, we demonstrated a correlation between laboratory tests and TEG parameters for this age period. The reference values provided herein are meaningful for future studies.

Paediatric reference intervals are heterogeneous and differ considerably in the classification of healthy paediatric blood samples.

The aim was to elude differences in published paediatric reference intervals (RIs) and the implementations hereof in terms of classification of samples. Predicaments associated with transferring RIs published elsewhere are addressed. A local paediatric (aged 0 days to < 18 years) population of platelet count, haemoglobin level and white blood cell count, based on first draw samples from general practitioners was established. PubMed was used to identify studies with transferable RIs. The classification of local samples by the individual RIs was evaluated. Transference was done in accordance with the Clinical and Laboratory Standards Institute EP28-A3C guideline. Validation of transference was done using a quality demand based on biological variance. Twelve studies with a combined 28 RIs were transferred onto the local population, which was derived from 20,597 children. Studies varied considerably in methodology and results. In terms of classification, up to 63% of the samples would change classification from normal to diseased, depending on which RI was applied. When validating the transferred RIs, one RI was implementable in the local population. Conclusion: Published paediatric RIs are heterogeneous, making assessment of transferability problematic and resulting in marked differences in classification of paediatric samples, thereby potentially affecting diagnosis and treatment of children. What is Known: • Reference intervals (RIs) are fundamental for the interpretation of paediatric samples and thus correct diagnosis and treatment of the individual child. • Guidelines for the establishment of adult RIs exist, but there are no specific recommendations for establishing paediatric RIs, which is problematic, and laboratories often implement RIs published elsewhere as a consequence. What is New: • Paediatric RIs published in peer-reviewed scientific journals differ considerably in methodology applied for the establishment of the RI. • The RIs show marked divergence in the classification of local samples from healthy children.

Clinical Utility of Platelet Count as a Prognostic Marker for Melioidosis.

Thromobocytopenia predicts mortality in patients with melioidosis in Thailand. We analyzed platelet counts in two large cohorts of melioidosis patients in tropical northern Australia to assess utility in a different clinical setting. Admission platelet counts were compared between subgroups of patients with different clinical outcomes. Patients with more severe disease (indicated by bacteremia, septic shock, and death) had significantly lower platelet counts than those with less severe disease. Logistic regression analysis was carried out for potential predictors of mortality among various clinical parameters, and platelet count was shown to be an independent predictor of mortality. Furthermore, in patients critically ill with melioidosis, an increasing platelet count after admission was associated with a significantly greater chance of survival. However, given that most patients with severe disease still had platelet counts within the normal range, platelet count is not a useful biomarker for predicting the severity of melioidosis in a clinical context.

Hematologic and serum biochemical reference intervals for wild eastern quolls (Dasyurus viverrinus): Variation by age, sex, and season.

BACKGROUND: The eastern quoll (Dasyurus viverrinus) is an endangered carnivorous marsupial that has recently suffered significant population declines. Several small captive breeding populations have been established, with plans to translocate wild and captive individuals to areas of their former distribution. Accordingly, hematologic and serum biochemical reference intervals (RIs) established from wild eastern quoll populations are essential for monitoring the health and disease status of both captive and wild populations, and to evaluate the health of individuals before, during, and after translocation. OBJECTIVES: We aimed to establish hematologic and serum biochemical RIs for wild eastern quolls, and examine the effects of age, sex, and season. METHODS: We collected a total of 202 hematologic samples, 309 packed cell volume samples, and 335 serum biochemical samples from 168 individual quolls between May 2011 and November 2013. Species-level RIs were established, as well as RIs of groups separated by age (juvenile, adult) and sex (adult male, adult female) using nonparametric, robust, and parametric methods. Seasonal variation in age- and sex-specific reference values was also assessed. RESULTS: Strong age and seasonal variation were evident in many hematologic and serum biochemical analytes, with significant variation observed in serum biochemical analytes between the sexes. CONCLUSIONS: The observed age, sex, and seasonal variation reflect differences in the timing of growth and reproductive stressors, which interact with seasonal energetic demands. Our findings highlight the importance of using age-, sex-, and season-specific RIs for clinical evaluation of eastern quolls, as species-level RIs will inadvertently smooth and mask important seasonal fluctuations that reflect reproductive status at different times.

Comparative evaluation of platelet counts in two hematology analyzers and potential effects on prophylactic platelet transfusion decisions.

BACKGROUND: Decisions on prophylactic platelet (PLT) transfusions are generally based on the recipient's PLT count, but few clinicians are aware of precision and accuracy of the PLT counting methods used by the clinical laboratory. Each PLT counting technology has its specific inaccuracy, especially in thrombocytopenic samples and therefore may impact decisions on PLT transfusions. STUDY DESIGN AND METHODS: Five routine PLT counting methods available in two hematology analyzers (Sysmex XN-2000 and Abbott CELL-DYN Sapphire) were investigated (impedance and optical on both analyzers and fluorescent on XN-2000), using the CD61 immunologic PLT method as a reference. The impact of counting inaccuracy on imaginary transfusion decisions was examined at various common PLT thresholds. RESULTS: In total 341 samples were analyzed, 178 of which had PLT counts of less than 35 × 109 /L. Despite excellent overall correlation with the reference method (r > 0.99), thrombocytopenic samples showed only modest correlation for impedance and XN-2000 optical methods. Sapphire optical and XN-2000 fluorescent methods correlated very well with the reference, albeit with bias in the very low range. We noticed potential risk of undertransfusion (ranging from 2% to 90%), depending on the threshold used. The risk of overtransfusion was small (<10%). CONCLUSIONS: The XN-2000 fluorescent PLT counting method showed excellent correlation with the CD61 reference count, closely followed by the CELL-DYN Sapphire optical method. XN-2000 impedance and optical and Sapphire impedance methods are not accurate enough for basing transfusion decisions on. Only XN-2000 fluorescent, Sapphire optical, and CD61 methods are sufficiently accurate for making appropriate clinical decisions in patients with severe thrombocytopenia.

Complete blood count reference intervals from a healthy adult urban population in Kenya.

BACKGROUND: There are racial, ethnic and geographical differences in complete blood count (CBC) reference intervals (RIs) and therefore it is necessary to establish RIs that are population specific. Several studies have been carried out in Africa to derive CBC RIs but many were not conducted with the rigor recommended for RI studies hence limiting the adoption and generalizability of the results. METHOD: By use of a Beckman Coulter ACT 5 DIFF CP analyser, we measured CBC parameters in samples collected from 528 healthy black African volunteers in a largely urban population. The latent abnormal values exclusion (LAVE) method was used for secondary exclusion of individuals who may have had sub-clinical diseases. The RIs were derived by both parametric and non-parametric methods with and without LAVE for comparative purposes. RESULTS: Haemoglobin (Hb) levels were lower while platelet counts were higher in females across the 4 age stratifications. The lower limits for Hb and red blood cell parameters significantly increased after applying the LAVE method which eliminated individuals with latent anemia and inflammation. We adopted RIs by parametric method because 90% confidence intervals of the RI limits were invariably narrower than those by the non-parametric method. The male and female RIs for Hb after applying the LAVE method were 14.5-18.7 g/dL and 12.0-16.5 g/dL respectively while the platelet count RIs were 133-356 and 152-443 x10(3) per µL respectively. CONCLUSION: Consistent with other studies from Sub-Saharan Africa, Hb and neutrophil counts were lower than Caucasian values. Our finding of higher Hb and lower eosinophil counts compared to other studies conducted in rural Kenya most likely reflects the strict recruitment criteria and healthier reference population after secondary exclusion of individuals with possible sub-clinical diseases.