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Daria Pašalić
Editor-in-Chief
Department of Medical Chemistry, Biochemistry and Clinical Chemistry
Zagreb University School of Medicine
Šalata ul 2.
10 000 Zagreb, Croatia
Phone +385 (1) 4590 205; +385 (1) 4566 940
E-mail: dariapasalic [at] gmail [dot] com

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S04-1

Jakšić B. S04-1: Clinical relevance of new blood cells parameters. Biochemia Medica 2009;19(Suppl 1):S38-S39.
Department of Internal Medicine, Merkur University Hospital, Zagreb, Croatia
Corresponding author: bjaksic [at] mef [dot] hr
 
Abstract
 
Automated blood cell counters are widely available and allow high volume and cost effective testing in clinical laboratories. Their continuous improvement in performance with high precision, accuracy and reproducibility of quantitative analyses has set up new standards in clinical practice. Over years, the need for complimentary analyses (usually manual analysis of blood morphology) is decreasing due to the fact that more and more aspects of “qualitative” morphological assessments are replaced by reproducible and precise quantitative measures. Moreover, advances in technology have provided a number of new parameters in automated evaluation of blood cells. For clinical hematology, traditionally rooted in blood cell morphology, this is emerging as a new challenge. The morphology is an important (probably still the most important) contributor to the evaluation of hematological disorders and their classification. This is due to the imminent comprehensive evaluation of blood cells taking into account various qualitative and quantitative aspects. However, the traditional morphology is also in continuous evolution, corroborating computer assisted image analysis, various staining procedures, immunological and molecular techniques etc., so that the discipline of hematological cytology is becoming more and more complex. In fact, both automated blood cell analyses and cytological morphology have converging evolution. The cytology is trying to describe and explore elements for morphological decision making process that could be quantifiable and therefore suitable for precise and reliable automated testing. By the same token, automated analyses are using more and more sophisticated multivariate approaches to define necessary clusters, thus mimicking decision process in multidimensional system.
Clinical relevance of novel parameters of blood cells must be assessed in methodologically sound clinical research process. Analysis of simple correlation with other tests is suboptimal. For automated white blood cells differential, the correlation with independent morphological assessment and ROC analysis may be adequate to show that automated analysis can substitute manual analysis at the desired level (this itself is clinically relevant if the morphology is used for diagnosis). However, failure to correlate with morphology may not be the failure to correlate with important clinical characteristic of a disorder under study. In other words, the new parameter may be more important for classification and consequent treatment than traditional morphology and therefore clinically more relevant. The example of changing paradigm in this direction is the new WHO classification of hematologic malignancies, based (in part) on molecular grounds. Clinical relevance and potential methodological pitfalls will be discussed on examples of published evaluation of red blood cell parameters (RDW, CHr, CHm, %HYPO, %HYPOm, %lowCHm; NRBC; IRF, LRF, MFR, HFR), platelets (MPV, “reticulated platelets“), and white blood cells. Relative low number of reports of evaluating the new parameters derived from automated hematological analyzers points to the lack of interest in the research community for cooperation in this field among clinicians, cytologists and laboratory experts. The awareness of new potential should be more readily disseminated among clinicians.
S04-2
Perović E. S04-2: Overview of some clinically relevant parameters of hematological analyzer ADVIA 2120. Biochemia Medica 2009;19(Suppl 1):S40-S41.
Zadar General Hospital, Zadar, Croatia
Corresponding author:edi_perovic [at] inet [dot] hr
 
Abstract
 
Hematological analyzer ADVIA 2120 uses laser light scatter technology for determination of blood count and differential. Using the Mie theory of light scattering for homogenous spheres, the low angle (2-3) and the high angle (5-15) scatters for each cell are transformed into volume and inner structure values (for erythrocytes - hemoglobin, for leukocytes – nucleus lobularity and for platelets – granules).
Conventional analytical systems for platelet counting usually are based on 1-dimensional cell size analysis and therefore methodological problem appears – ability to dicriminate platelets from nonplatelet particles of comparable size. Those are usually fragmented RBCs, microcytes, debris and there is overlaping of microcytes and giant platelets.
2D-platelet analysis reveals the new parameters – platelet indices: MPV is a measure of size, MPC is mean platelet component concentration, MPM is mean platelet mass, PCDW is platelet component distribution width and PMDW is platelet mass distribution width. The use of platelet indices found its place in the assessment of in vitro platelet activation because during this process platelets undergo shape change, swelling and degranulation occurs.
Among platelet indices, MPC is the marker of platelet activation, which negatively correlates with the increase in the expression of CD 62P. This decreasing of MPC could be inhibited by Ridogrel, a specific inhibitor of thromboxane synthesis. Application of other platelet indices showed to be useful in the assessment of platelet storage lesion, and thus the quality of platelet concentrate. Determination of platelet indices can be used for defining high risk patients and to monitor platelet response to anti-platelet therapies in patients undergoing angioplasty. Platelet activation indices are changed and in patients with acute heart failure, in severe hypertensive disease, and showed the prognostic information for survival of patients who had DIC.
Analysis of WBC takes place on two different measurement channels, one to measure myeloperoxidase activity and size of cells, and another to measure nucleus granularity and size of cells. The fact that blast cells could be analyzed in both measuring channels indicates increased sensitivity and specificity of this parameter, which is still in hematological analyzer expressed as flag parameter. The large unstained (peroxidase-negative) cells are used for diagnosing and monitoring of acute leukemia and myelodysplastic syndrome, considered to be a prognostic factor in B-CLL and in viral infectious diseases. LUC population increases during neutropenic phase and during recovery phase after standard doses of chemotherapy. LUC absolute number positive correlate to the absolute number of blast, CD 34+ and CD3+/CD4+ cells before nadir phase during chemotherapy cycle. After this phase LUC cells show a positive correlation with CD2+ / CD56+ cells (NK-cells).
LUC cells showed a negative correlation with the number of neutrophil granulocytes and with the MPXI (myeloperoxidase index). MPXI was found to be a potential biomarker for monitoring the clinical activitiy of G-CSF, it grows in patients with neutropenia treated with G-CSF, and shows a rapid decrease in prenadir phase of chemotherapy. Percentage of LUC cells and value of MPXI are markers of the nadir phase and may be helpful in predicting the duration of neutropenia. Prognostic significance of LUC cells and MPXI was shown in patients who are recovering from significant neutropenia taking G-CSF. The fast recovering patients show prenadir phase hematological profile: low MPXI, increased number of blasts and CD34+/CD45+ cells, and a high increase of LUC cells.
S04-3
Tornow T.S04-3: Canalising the data flood: The Case Manager combines laboratory data with clinical knowledge. Biochemia Medica 2009;19(Suppl 1):S41-S42.
Sysmex Europe GmbH, Marketing Diagnostic Concepts, Norderstedt, Germany
Corresponding author:Tornow [dot] Tanja [at] sysmex-europe [dot] com
 
Abstract
 
With the ever growing number of available parameters and methods in the modern laboratory it is becoming more and more difficult for the clinician to keep track and also to be able to decide: What is necessary and - more importantly - what is possible?
Sysmex’ new top end analyzer the XE-5000 Case Manager for example now offers a total of 79 parameters for whole blood and body fluid analysis. Some of the newer extended parameters like the immature platelets (IPF) have proven their clinical utility in recent years. But their potential is not known to all users in the lab or to clinicians on the ward just yet. Moreover, often a specific combination of parameters and results is essential for certain diagnoses.
With a new diagnostic concept the XE-5000 Case Manager is introducing a solution to this problem. It is the first haematology analyzer with integrated diagnostic algorithms for easier patient results interpretation and therapy monitoring. It combines new product performance specifications, advanced analytical parameters with proven clinical utilities like immature granulocytes (IG) or the haemoglobinisation of reticulocytes (RET-He) and available patient information, and notifies the user of specific patient cases and conditions. It reports an example case, supplies information about the underlying disease, the relevant parameters and the diagnostic process. As such the Case Manager assists the lab physician not only to report but also to interpret the relevant and important clinical information, supporting the clinician on the ward most efficiently in quick diagnosis and therapy monitoring.
S04-4
Tandara L.S04-4:Possibilities and limitations of haematology analyzers in the severe thrombocytopenic range. Biochemia Medica 2009;19(Suppl 1):S42-S43.
Department of Laboratory Diagnostics, Split University Hospital Centre, Split, Croatia
Corresponding author:leida [dot] tandara [at] gmail [dot] com
 
Abstract
 
Routine haematology analyzers (HA) employ several technologies to count platelets: impendance principle, optical light scattering, optical fluorescence and automated immunoplatelet CD61 count. Although considerable improvement has been made (fitted curve of PLT histogram, changing treshold between PLT and RBC, multi angle scatter) some problems considering the PLT counting persist. The major problem is discrimination of PLT from similar sized particles such as RBC microcytes, RBC fragments, WBC cytoplasmic fragments or immune complexes that may be errorneously included in platelet count. In some pathological situations PLT demonstrate high volume and for that reason may be excluded from PLT count. Some HA combine two principles and simultaneously determine PLT count by both principles, so discrepancies between the two counts generate an alert flag suggesting the presence of sample interference. International Reference Method (IRF) for PLT counting is immunological method using flow cytometry, two monoclonal antibodies to surface PLT antigens (CD61 and CD41) conjugated to fluorphore. PLT count is derived from PLT/RBC ratio.
The use of prophylactic platelet transfusion for patients without bleeding is based on a threshold principle. The optimal treshold for prophylactic platelet transfusions in haematology patients is still not clear. For a long time a treshold of 20 x 109/L has been used. At present a trigger of 10 x 109/L is generally recommended for thrombocytopenic patients without additional risk factors such as sepsis, concurent use of antibiotics or other abnormalities of haemostasis. Accurate platelet count is critical in clinical practice to facilitate decisions at prophylactic platelet transfusion tresholds. The impact of interferences at these low level becomes higher because number of interffering particles in sample may even exceed the true number of platelets.
Several studies compared PLT counts obtained by available routine counting technologies and IRF method at very low platelet counts (PLT < 20 x 109/L). Studies highlight the inaccuracies of HA at this low level. Majority of methods tended to overestimate the platelet count. In different studies automated CD61 Immunoplatelet count, routinely available on only one type of HA (Cell Dyne Sapphire, Abbott), gave the best agreement with IRF which is not unexpected because both immunological methods are measuring the same pharametar although with some methodological differences. There were also significant differences in PLT count between the same type of analyzer at different centeres, which were attributed to calibration differences. It is concluded that haematology laboratories should establish the accuracy of different HA used in laboratory at the recommended transfusion tresholds in clinical practice.
New IRF, replaced the old manual phase microscopy method, should provide a suitable reference material to improve the calibration of HA in thrombocytopenic range as well as adequate QC material and potentially have an impact on platelet transfusion decision making. If there is a confidence in the platelet count at low levels, then it would be possible to lower safely the prophylactic transfusion trigger and reduce platelets transfusions to only those that are necessary, reduce patient exposure to blood component and conserve transfusion resources.
S04-5
Simon R.S04-5: The new tecnologies and innovations in Laboratory Hematology. Biochemia Medica 2009;19(Suppl 1):S44.
Cellular Analysis Beckman Coulter Eurocenter, Nyon, Switzerland
 
Abstract
 
The author did not provide an abstract.