Automated Blood Count Research Articles

Variable levels of carry over on platelet counts ≤20 × 109/l with the Bayer Advia 120

Accurate platelet counts are essential for the safe management of severe thrombocytopenia (platelet counts < or = 20 x 10(9)/l). The effect of carry over on platelet counting in severe thrombocytopenia was investigated by performing counts before and after saline rinses on three Bayer Advia 120 automated blood counters. Counts were performed in both primary and manual closed tube system modes on two instruments and in manual open tube mode on a third. A total of 194 samples with platelet counts < or = 20 x 10(9)/l were studied. First counts were significantly higher in all groups. The magnitude of the difference varied both by analyser and counting mode. Carry over was minimal with one analyser in primary mode and second counts were on average only 5.5% lower; on a second analyser in manual closed tube system mode second counts were on average 37.7% lower. A first count of > or = 10 x 10(9)/l fell to <10 x 10(9)/l on the second count in 35 of 145 samples (24.1%). In five such samples, all tested on one analyser, the second count was <50% of the value of the first count. Two of 49 (4.1%) first counts of <10 x 10(9)/l increased to > or = 10 x 10(9)/l on repeat. These results show a variable and often potentially clinically important carry-over effect on severely thrombocytopenic samples using the Advia 120.

Analytical Features of the New Red Blood Cell and White Blood Cell LH750 Research Population Data.

Recently, a new set of parameters produced by the Beckman-Coulter's GEN'S, LH500, LH750 and the latest LH780 automated blood counters, derived from leukocyte and red cell's morphological data by means of the VCS technology are available and can be printed as research data together with the leukocyte differential and reticulocyte analysis. With the use of these Research Population Data (RPD) parameters several recent publications have shown their usefulness for the diagnosis of malaria (Fourcade et al), sepsis (Chaves ), apoptosis detection (Lab hem 2005) and the diagnosis and differentiation of lymphoptoliferative disorders (Silva M et al)In order to evaluate the analytical behaviour of these newly described red blood cell and leukocyte morphological parameters in routine bood samples and in the Beckman-Coulter's calibration and control 5C, we conducted a study to evaluate the paramters' precision and performance during short and long term sample's storage:Precision: 10 samples from normal individuals were analyzed 10 times and the CV for each parameter was calculatedShort term stability stability at 4C and 22C: 5 normal samples were evaluated from the time of blood drawing until 5 hours later, both at room temperature (22C) and at 4 CLong term stability at 4C: 15 normal samples were evaluated at various times after blood drawing, from 4 hours (which was found to be the best time for sample analysis in the short term stability study, above) up to 77 hours after blood withdrawal.Control and Calibration with 5C: We evaluated the performance of the research parameters in the 5C by running the same batch of 5C control in 5 different counters from 4 different centers, comparing the results with those from 5 normal individualsStability in a period of time: We have evaluated every week during two months 15 normal samples, recording the temperature and the avergae of all RPD values.RESULTSPrecission: The CV% for the Mean Volume, Conductivity and Scatter of the different leukocyte types was always less than 1%, with an average of 0,6%. The CV% for the Standard Deviation of Volume, Conductivity and Scatter varied between 2.45% and 7.7%, wit an average of 4.9%. The CV% of any SD always being higher than the primary parameter.Short term stability: We observed no significant differences between samples kept at 4C and 22C during the first 5 hours after blood drawing. During the first two hours, however, minor fluctuations in results occurred, always <5%, being preferable to test the samples after blood stabilization, between 2 and 5 hours after withdrawal.Long term stability: The stability of the research parameters after 9 hours is best when the samples are kept at 4C, but the differences are not clinically significant up to 17 hours and, for some parameters, up to 24 hours after blood drawing.The comparison of the RPD research parameters from normal samples and from the Beckman's 5C control showed good correlation in the different counters and the different centers. When the results from the 5C were higher or lower, the results from the normal samples were concordantly higher or lower respectively, The correlation coefficient was 0.98 for the Mean Volume and 0.92 for the Mean ConductivityThe Stability of RPD values was acceptable during the period evaluated (2 m.)with changes lower than 3%.CONCLUSIONS: The results of the present study show that from the analytical stand point, precission, stability and possibility of calibration, these Research Population data are equivalent to those of other laboratory tests performed by modern instruments.

High frequency of maternal vitamin B12 deficiency as an important cause of infantile vitamin B12 deficiency in Sanliurfa province of Turkey

Vitamin B12 deficiency in infancy may cause failure to thrive, severe neurological disorders and megaloblastic pancytopenia. It is well known that infants born with deficient vitamin B12 storage have increased the risk of vitamin B12 deficiency. Vitamin B12 deficiency is more prevalent in infancy in Sanliurfa province (at the southeast region of Turkey). The aim of this study was to determine the frequencies of vitamin B12, folic acid and iron deficiencies in pregnants and their babies at birth and to what extend the mothers' deficiency becomes effective on babies' deficiencies. The study groups were constituted by 180 pregnant women and their single and term babies. Venous blood samples of pregnants were obtained 1-3 h before delivery and babies' cord bloods were collected at birth. Vitamin B12 and folic acid levels were measured with electro chemiluminiscence method; serum iron and iron binding capacities were measured by colorimetric method and complete blood counts were performed by automatic blood counter. Mean vitamin B12 levels in maternal and cord blood serum were 130 +/- 61.7 pg/ml and 207 +/- 141 pg/ml; mean folic acid levels were 8.91 +/- 6.46 ng/ml and 17.8 +/- 11.8 ng/ml; mean serum iron levels were 56.9 +/- 37.5 microg/dl and 147 +/- 43.2 microg/dl; and mean transferrin saturations were 11.8 +/- 8% and 65.6 +/- 24%, respectively. There were vitamin B12 deficiency (<160 pg/ml) in 72% of the mothers and 41% of the babies, and severe deficiency (<120 pg/ml) in 48% of the mothers and 23% of the babies. Folic acid deficiency was found in 12% of the mothers, but was not found in the babies. There were iron deficiency in 62% of the mothers and 1% of the babies. There were statistically significant correlation between maternal and cord blood serum vitamin B12 levels (r = 0.395, P < 0.001) and folic acid levels (r = 0.227, P = 0.017), while there were no correlation between maternal and cord blood iron levels and transferrin saturations. The study results showed that vitamin B12 deficiency is prevalent in pregnants in this region and that 41% of infants have born with deficient vitamin B12 storages. Therefore, prophylactic use of vitamin B12 by pregnant women in Sanliurfa and other poor communities could have considerable benefits to prevent vitamin B12 deficiency and its complications in infants.

The effect of pre-eclampsia on complete blood count, platelet count and mean platelet volume

Pre-eclampsia is a condition observed during pregnancy and threatens the life of both mother and foetus. There are studies, which suggest platelets play a major role in the pathogenesis of pre-eclampsia. The aim of this study is to compare the complete blood count (CBC) parameters, especially platelet count and mean platelet volume (MPV), in pre-eclamptic and normal pregnant women and to evaluate whether these parameters have a prognostic significance in determining the severity of eclampsia. The study and control groups consist of 56 pre-eclamptic and 43 normal pregnant women, respectively. There was no statistically significant difference according to CBC, platelet count and MPV when pre-eclamptic and severely pre-eclamptic patients were compared with controls. As a result, we observed no prognostic significance of CBC, platelet count and MPV on the presence and/or severity of pre-eclamptic condition. There are conflicting results especially on the significance of MPV in the literature, and possibly this confliction is due to the difference between methods and/or equipments used for automated blood count.

Hematopoietic progenitor cells (HPC) and immature reticulocytes evaluations in mobilization process: new parameters measured by conventional blood cell counter

Monitoring the timing of leukapheresis in peripheral blood stem cells (PBSC) mobilization is an important clinical decision that requires an accurate analytical tool. The present study assessed hematopoietic progenitor cells (HPC) and immature reticulocyte fraction (IRF) counts provided by a routine automated blood counter as potential parameters for predicting the appropriate time for harvesting. The HPC and IRF values were compared with white blood cell (WBC) and CD34+ cell counts obtained by flow cytometry in 30 adult patients with hematological malignancies undergoing PBSC mobilization. It was observed that there was a significant correlation between HPC counts and CD34(+) cells in peripheral blood counts (r=0.61, P=0.0003) and between the number of HPC and CD34+cells collected by leukapheresis (r=0.5733, P=0.0009). Comparing HPC, IRF, WBC, and CD34+ cells parameters as a sign of hematological recovery showed that the raise in immature reticulocytes counts preceded the increase of WBC (P=0.0002), HPC (P=0.0001), and CD34(+) (P=0.0001) cells in peripheral blood counts. According to our results, HPC and IRF parameters may be integrated into clinical protocols to evaluate the timing of leukapheresis. IRF, as previously demonstrated in bone marrow transplantation, is the earliest sign of hematopoietic recovery in mobilization process.

Newborn screening for severe combined immunodeficiency (SCID): a review

Because prompt intervention may prevent complications, early diagnosis is important in many inherited metabolic diseases. Early diagnosis of Severe Combined Immunodeficiency (SCID) is critical - because chances for successful treatment are highest for infants who have not yet experienced severe opportunistic infections. SCID is a rare disease that can be detected in newborn infants (i.e., those more or equal 1 month of age) by automated blood count and manual differential. Early diagnosis of SCID is rare since, because estimates of the incidence rate range from one in 50,000 to 100,000 births, most pediatricians do not routinely count white blood cells in newborns. Tests for T-cell lymphopenia (TCLP) using dried blood spots (DBS) could be used to identify children with SCID - as well as for other immunodeficiencies that would not be apparent until after the child developed an infection. Screening newborns for SCID would allow early diagnosis and treatment -- as well as genetic counseling for the family.

Mean platelet volume in Type 2 diabetic patients

Background: Altered platelet morphology and function have been reported in patients with diabetes mellitus. They are likely to be associated with the pathological processes and increased risk of vascular disease seen in these patients. We aimed to determine the mean platelet volume (MPV) in diabetics compared to nondiabetics, to see if there is a difference in MPV between diabetics with and without macro- and microvascular complications, and to determine the correlation between MPV and fasting blood glucose, glycosylated hemoglobin (HbA1c), patient age, and duration of diabetes, respectively. Methods: We measured MPV in 145 consecutive Type 2 diabetic patients and 100 nondiabetic control subjects without known coronary artery disease who had complete blood count on venous blood sample taken into tripotassium EDTA, using a Roche Minos cell counter and automatic blood counter (CELL-DYN 3500). The blood glucose level was measured by glucose oxidase method and HbA1c by calorimetrical method in the autoanalyser. Statistical evaluation was performed by SPSS for Windows statistics programme using multivariate logistical regression analysis, Student's t, and Pearson correlation tests. Results: MPV was significantly higher and the mean platelet counts were significantly lower in diabetics compared to age- and sex-matched nondiabetic healthy controls [10.62±1.71 fl vs. 9.15±0.86 fl (P=.00), 260.38±68.65×109/l vs. 292.33±79.19×109/l (P=.001)], respectively. Conclusions: Our results show significantly higher MPV in diabetic patients than in the nondiabetic controls. This suggests that platelets may play a role in the micro- and macrovascular complications of diabetic patients.

Overestimation of Hemoglobin in a Patient With an IgA-κ Monoclonal Gammopathy

Abstract A patient with multiple myeloma had an automated blood count performed on a Coulter STK-S counter that repeatedly failed internal limits for both mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration. The calculated hematocrit agreed with a spun hematocrit, suggesting that the hemoglobin concentration was being overestimated by the automated counter. Measurement of the plasma hemoglobin concentration of the sample, which showed no visible hemolysis, gave a hemoglobin concentration of 32 g/L on the STK-S analyzer. Correction of the whole blood hemoglobin using the plasma hemoglobin gave a value consistent with the hematocrit. The corrected mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration values were within standard limits. This patient's paraprotein was characterized as IgA-κ and was present at a concentration of 61 g/L. The hemoglobin concentration measured on whole blood by Sysmex NE 8000 and Technicon H*1E autoanalyzers agreed reasonably well with the corrected result from the STK-S.

Mean cell haemoglobin concentration in subjects with haemoglobin C, D, E and S traits

The Bayer H1 automated blood counter was used to assess the MCHC values of 40 nonanaemic patients with HbC trait, 21 with HbD trait, 23 with HbE trait and 69 with HbS trait. These were compared with values from controls with a normal Hb phenotype. Values were significantly higher in those with HbC, D and S traits and approached significance in those with HbE trait. In 45%, of subjects with HbC trait the MCHC value was > or = 35 g/dl. Such values may prove a useful marker for this abnormality. In a further 12 patients with HbC, D, E or S traits and coexisting iron deficiency anaemia, MCHC values were usually higher and the percentage of hypochromic cells (red cells with CHC <28 g/dl, directly measured by the H1) usually lower than values derived from controls with a normal Hb phenotype and iron deficiency anaemia of similar degree. In individuals with HbC, D, E or S traits, the MCHC and proportion of hypochromic cells are less sensitive indicators of iron lack than in subjects with a normal Hb phenotype.

Screening criteria for beta thalassaemia trait in pregnant women.

To establish suitable screening criteria for beta thalassaemia trait during pregnancy using an automated blood counter incorporating light scattering technology. Pregnant women (n = 857) at a London antenatal clinic were investigated for beta thalassaemia trait if the Technicon H.2 full blood count showed either a mean corpuscular volume (MCV) < 85 fl or a mean corpuscular haemoglobin (MCH) < 27 pg. Results were then analysed to establish which of these variables was more suitable for screening and to determine suitable cut off points for calculating the haemoglobin A2 percentage. The MCH was superior to the MCV for thalassaemia screening as it was a more stable measurement and fewer unnecessary tests were performed. A MCH less than 27 pg is a suitable cut off point for screening. This screening criterion was equally applicable to a Coulter impedance counter. Pregnant women presenting at an antenatal clinic with a MCH < 27 pg should be investigated further to confirm or exclude a diagnosis of beta thalassaemia trait.

Inaccurate haemoglobin estimation in Waldenstrom's macroglobulinaemia: unusual reaction with monomeric IgM paraprotein.

Automated blood counts from a patient with Waldenström's macroglobulinaemia repeatedly failed critical limit standards set for mean cell haemoglobin concentration and mean cell haemoglobin. Haemoglobin estimation was higher than that suggested by clinical examination, symptoms, and the spun haematocrit. This was found to be due to an interaction between the Coulter lysing agent and monomeric IgM paraprotein in the patient's plasma, creating a precipitate which was optically dense at 525 nm.

Alterations in the immune system in cats fed diets with excess cystine

As part of an ongoing biochemical study in nutrition we examined blood profiles, serum chemistry, lymphocyte transformation and lymphoid pathology in cats fed a diet containing 5% cystine with and without taurine. Automated blood counts of whole blood samples showed a decrease in red blood cell counts accompanied by a significant decrease in hemoglobin and hematocrit in cats fed 5% cystine in the absence of taurine compared to cats fed 0.05% taurine (control). A significant increase was noted in serum cholesterol in cats fed cystine and cystine/taurine compared to cats fed control diets. There were no significant differences in lymphocyte transformation using leukocytes isolated from the spleen and blood with the mitogens, phytohemagglutinin and pokeweed. However, lymphocyte transformation of both spleen and blood without mitogen from the excess cystine group were significantly higher than leukocytes from the 0.05% taurine group (control). Pathological examination of regional lymph nodes, livers, and spleens showed histological abnormalities in cats fed the excess cystine diet. These results indicate that there are alterations in the immune system of cats fed a diet containing 5% cystine with and without dietary taurine.

Automated blood count analysis by trimodal size distribution of leukocytes with the SYSMEX E-5000.

The automated haematology analyser, SYSMEX E-5000, measures and computes quantitative haematological parameters, and determines the size distribution of blood cells and platelets. After partial lysis, the analyser classifies the leukocytes into 3 populations: small cells (lymphocytes), intermediate sized cells (basophils, eosinophils, monocytes) and large cells (neutrophils, including band cells). One thousand blood samples from inpatients and outpatients were analysed automatically in the SYSMEX as well as being submitted to microscopic blood smear differentiation, and the results were compared. The trimodal size distribution of the automated analysis revealed 1.8% false normal results. Ten cases of eosinophilia of between 6.6 and 12.5% remained undetected by the automated method, which also failed to detect 7 cases of left shift with normal leukocyte count, as well as a single sample containing 2% of myelocytes. Both diagnostic sensitivity and diagnostic specificity were high, i.e. 97.1% and 81.8%, respectively. The predictive values were also high for both pathological and normal results. Since certain changes in blood cell morphology are not detected by the SYSMEX, certain clinical indications still call for a microscopic blood smear examination. With due regard to these limitations, the apparatus yields reliable results and economizes considerably the routine laboratory work load. In the present study, 31% of the microscopic blood cell differential counts were saved by using the SYSMEX E-5000.

Book Reviews

Journal Article Book Reviews Get access Automated Blood Counts and Differentials: A Practical Guide.Bessman J. David, MD. Baltimore, The Johns Hopkins University Press, 1986, 150 pages with index, $35.00. Joanne Cornbleet, MD Joanne Cornbleet, MD Stanford University Medical Center, Stanford, Calif. Search for other works by this author on: Oxford Academic PubMed Google Scholar Laboratory Medicine, Volume 19, Issue 10, 1 October 1988, Page 682, https://doi.org/10.1093/labmed/19.10.682 Published: 01 October 1988

Red Blood Cell Fragmentation: Improved Detection and Identification of Causes

The peripheral blood film and the red blood cell size distribution histogram were examined for evidence of red blood cell fragments in 2,350 subjects. To distinguish subjects with greater than or equal to 10 fragments/1,000 red blood cells (abnormal) from normal, examination of the blood film was 0.83 sensitive and 0.30 specific, whereas examination of the histogram was 0.97 sensitive and 0.87 specific. The most common causes of abnormal fragmentation were malignancy with cytotoxic chemotherapy and severe iron deficiency. In two subjects, an abnormal red blood cell fragmentation pattern was the clue to a spectrin mutant in subjects with an automated blood count previously evaluated as normal. The data suggest two conclusions: the red blood cell volume histogram appears more accurate than the peripheral blood film for routine identification of red blood cell fragments; and asymptomatic spectrin abnormality identifiable by abnormal histogram may be a relatively common disorder.

The "diff-if". Use of microcomputer analysis to triage blood specimens for microscopic examination.

Increasingly, all automated blood counts are not accompanied by a microscopic white blood cell differential. A popular strategy is to obtain a manual differential if any part of the automated blood count and differential is outside specified limits (the "diff-if" strategy). The authors compared two sets of criteria to triage blood counts for manual differentials: previously recommended numeric values, and the analysis of a microcomputer program. In a population of subjects with a high percentage of hematologic disorders, the microcomputer program and the numeric criteria were equally specific (excluding normal blood smears); the program was more sensitive for bands, immature granulocytes, monocytes, nucleated red blood cells, reticulocytosis, teardrops, red blood cell fragments, and hypersegmented neutrophils. The numeric criteria were more sensitive for eosinophilia (less than 1.0 X 10(9)/L) and mandated fewer manual differentials. In a population of predominantly normal subjects, the program was more sensitive for increased bands and equally sensitive for eosinophilia, the only abnormalities observed on the smear. In a population of subjects with predominantly abnormal blood counts, but excluding most primary hematologic disorders, there were few blood smears with abnormalities beyond eosinophilia or increased bands. In both of these groups, the computer program mandated more manual differentials than did the numeric criteria. The authors conclude that microcomputer analysis by the program tested was more sensitive than numeric criteria to identify specimens with abnormal blood smears. Specificity depended on the patient population. The choice of a triage strategy should be based on the individual laboratory's patient population.

Interactions of Liposomes and Platelets

Rats were injected intravenously with liposomes of various compositions and sizes and blood platelet count measured. It was found that negatively-charged liposomal systems produced a transient reduction in platelet count in the first 5 minutes after injection which recovered by 60 minutes post-injection. This effect was most striking for multilamellar vesicles (MLV's) containing phosphatidylglycerol (PG). Dose levels of 25 mg/kg of MLV's containing 10 mole% PG caused the platelet count to drop from a control value of 1,086 +/- 21 X 10(9)/l to 193 +/- 14 X 10(9)/l by 2 minutes post-injection, an 82% decline. This thrombocytopenic effect was observed to diminish as vesicle size or vesicle dose was decreased. Positively-charged liposomes produced a less pronounced transient reduction in platelet count while neutral liposomes caused only a mild, transient platelet decline. This transient thrombocytopenic effect was not blocked by common anticoagulants and fibrinolytic agents but was prevented by liposomal pretreatment. Radiolabeled platelet studies revealed that transient sequestration of platelets occurs in the liver and spleen 2 minutes after PG:EPC:CHOL MLV injection with a normalization of platelet distribution by 60 minutes post-injection. In vitro studies, using an automated blood counter, suggest a transient association of liposomes and platelets occurring following injection. Liposomally-induced transient thrombocytopenia suggests a role for platelets in the biodistribution of liposomes.

Information for decision makers at hospital laboratory level: An example of a graphical method of representing costs and effects for a replacement automated technology in a haematology laboratory

The costs and effects on patient management following the introduction of a fully automated blood count analyser have been evaluated for a hospital haematology laboratory in England, during 1985. In the case of the relatively high throughput observed in the laboratory studied, the automated technology was judged to be cheaper if considering laboratory-centred costs alone. But this was no longer necessarily the case once wider costs, including extra medical workload generated for hospital and community physicians, were included. Effects on patient management were measured for all types of patient, including hospital in-patients, out-patients and general practice patients. A graphical method allowing comparison of the costs and effects of the replacement automated system, termed a Technology MAP (Management Awareness Profile) is presented in the paper. MAPs provide a flexible information display which can be tailored to an individual laboratory's situation producing an overall picture of expected costs and effects on patient management following the introduction of a new technology—a full value-in-use assessment. The authors argue that there is a need for a central source of such value-in-use assessments, especially for new medium-priced diagnostic technologies which are likely to become widely spread in Britain.

Evaluation of BCDE, a microcomputer program to analyze automated blood counts and differentials.

A microcomputer program (BCDE) has been developed to analyze automated blood cell counts and differentials' similarity to normal values or to 36 disease categories. In 50 normal subjects, the analytic program listed the correct diagnosis as the first diagnosis in 49 cases (the only diagnosis in 44) and second of two diagnoses in one case. In 182 subjects with known hematologic disorders, the correct diagnosis was listed first in 134 and second or third in an additional 40. Subjects with iron deficiency, heterozygous thalassemia, immune thrombocytopenia, anemia of chronic disease, reactive thrombocytosis, acute infection, and chronic leukemia had the disorder identified as the most likely one by the analytic program with both sensitivity greater than 80% and specificity greater than 98%. Subjects with acute leukemia, folate deficiency, sickle cell anemia, cytotoxic chemotherapy, and chronic liver disease had the disorder identified as most likely by the program with a sensitivity less than 80%. In a different 11 cases with known hematologic status, a panel of 37 physicians identified the disorder(s) or normality only 72% of the time, whereas the analytic program listed the correct diagnosis first in 10 of 11 (91%). The analytic program appears useful for both triage of normal from abnormal data and for the initial differential analysis of abnormal data.

Automated Blood Counts and Differentials. A Practical Guide

Automated Blood Counts and Differentials. A Practical Guide