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This is a prospective study realized at the level of the hematology department and blood transfusion center of the University Hospital Center (CHU) of Dr Ben Badis of Constantine and spread out over a period of one year (from January 1st to December 31st). The work focused on the analytical processes mastery of the NFS needs a compulsory step concerning technical and organizational laboratory skills respecting the ISO 15189 laws going through a mastery of support processes (humain resourses, informatics, materials, documents, management) indispensable for the good function of analytic proceedings, a performance evaluation of the hematology analyzer Advia (2120 I and II and 560) and quality control management (intern, extern). The analytic performance evaluation of Advia gives reliable results reproductible and stable for use of the routine automatisation good inter-machine correlation and laboratory performance in terms of the quality extern evaluation with military hospital laboratory.

Menometrorrhagia is a frequent bleeding symptom in young women, and may be related to an inherited bleeding disorder. If there is no gynecological etiology, hemostasis tests are required. The early medical management of these teenage girls is important, especially when a bleeding disorder is known. The bleeding risk of the first periods may then be anticipated. Afterwards, the objective of the treatment is to keep the bleeding symptoms under control: anti-fibrinolytic treatment, specific replacement therapy for bleeding disorder and hormonal treatment. This management requires a multidisciplinary medical team, mainly hematologist and gynecologist, all along the genital lifespan, from the first periods to the desire for pregnancy., Competing Interests: A. Harroche déclare des liens ponctuels -interventions et prises en charge lors de congrès- avec Novo Nordisk, Bayer, Pfizer, Shire, Octopharma, LFB, CSL Behring, Sobi et Roche. S. Meunier déclare des liens ponctuels interventions et/ou prise en charge lors de congrès- avec Novo Nordisk, Bayer, Shire, Baxalta/Shire, Octapharma, Pfizer, LFB, CSL-Behring, Sobi et Roche. S. Da Costa déclare n’avoir aucun lien d’intérêts. C. Falaise déclare des liens ponctuels -interventions et/ou prise en charge lors de congrès avec Bayer, Octopharma, Pfizer, Roche, SOBI, Takeda, LFB et Novo Nordisk. C. Oudot déclare des liens -prise en charge lors de congrès avec Shire, Bayer, SOBI, CSL Behring, Octopharma et Novo Nordisk.

Introduction: The choice of an automaton of haematology is a determining stage, which has to take into account at the same time the quality of the results and the economic imperatives: workload, structure and organization of the laboratory., Material and Methods: [corrected] It is in this spirit that we estimated during a period of 3 months the analyzer of haematology: the HmX™ Coulter with boatman of samples of the company Beckman. This automaton realizes the blood numeration, the formula leukocytic and the reticulocyte count. At first, we estimated the appropriate characteristics of device. Secondly, we estimated the relevance, the sensibility and the specificity of the alarms by comparing with the reference method, which is the optical microscopy. For that purpose, 125 blood smears resulting from service of haematology and from resuscitation were examined in optical microscopy. The technical tests were realized according to the recommendations of the International committee for evaluation of automatons of haematology., Results: The analytical performances were satisfactory in particular the big interval of linearity and the absence of contamination. As regards the evaluation of the alarms system: rate of rejection is 63%, the sensibility 86%, the specificity 70%, the positive predictive value 80%, the negative predictive value 78% and the efficiency 80%. The alarms myelaemia and atypical lymphocytes were never sources of false negatives. The alarms erythroblasts and platelet aggregates did not engendered positive forgery. The blast cell alarm was responsible for a single case of false negative., Conclusion: The faithfulness of automaton is satisfactory: the absence of contamination, the big interval of linearity for the leukocytes, the red blood cells and the platelets as well as a good relevance of the alarms with regard to the anomalies found on the peripheral blood smear. From the user-friendliness and practicability point of view, the HmX™ Coulter was deeply appreciated., (Copyright © 2013 Elsevier Masson SAS. All rights reserved.)

The schistocytes are fragmented red blood cells mainly observed in the setting of hemolytic anemias and particularly among the thrombotic microangiopathies. The presence of schistocytes is an important criterion for the diagnosis of mechanical anemias, though the identification of these cells remains problematic. As a high variability of the morphologic identification criteria of the schistocytes among morphologists has been observed, some guidelines have been proposed after workshops (French and Italian groups). The International council for standardization in hematology published a consensus in November, 2011. The French group of cellular hematology (GFHC) aimed to recover the opinion of French biologists directly confronted to schistocytes measurements. 169 out 500 (34%) answered 10 questions dealing with the identification and measurements of schistocytes as proposed by the ICSH guidelines. A consensus was reached for the urgent need of guidelines documents, moreover in the current background of the European accreditation NF EN ISO 15189 rules. A traduction in native (French) language as warmly wished in order to facilitate the diffusion of the information. New fragmented red cell parameter recently provided by 2 manufacturers of automated blood cell counters remained doubtfull for routine use for half of the biologists.

Using hematology analysers, white blood cell (WBC) counts and differentials (either three or five parameters) may be ascertained after Red Blood Cell (RBC) lysis and analysis using either impedance and/or optical (laser) technology. Cells or particles not destroyed by lytic agents are enumerated as WBC: abnormal particles may be observed on WBC differential scattergrams, if performed, appearing as a variable number of dots, which location may help to ascertain the nature of the abnormality. Spuriously low WBC counts are rare, mainly related to agglutination in the presence of ethylenediamine tetra-acetic acid. Cryoglobulins, lipids, insufficiently lysed RBC, erythroblasts and platelet aggregates are common situations increasing WBC counts. So far, many current high performance analysers clearly identify and enumerate erythroblasts now. In normal patients and in reactive disorders automated differential provides true and accurate results. However, failure to enumerate accurately basophilic granulocytes and monocytes is not uncommon. Using myeloperoxidase cytochemistry to ascertain differential may lead to slide review if the enzyme expression is low or absent. Low number of abnormal cells (blasts, lymphoma cells, dysplastic granulocytes) may be missed, more frequently if leukopenia is present. In many but not all instances flagging and/or an abnormal WBC differential scattergram will alert the operator. Although these flags are sensitive enough to allow the identification of several spurious counts, only the most sophisticated analysers have optimal flagging, whereas more simple ones, especially those without a WBC differential scattergram, do not demonstrate the same sensitivity for the detection of abnormal results.

Several situations lead to abnormal haemoglobin measurement or to abnormal red blood cells (RBC) counts, including hyperlipemias, agglutinins and cryoglobulins, haemolysis, or elevated white blood cells (WBC) counts. Mean (red) cell volume may be also subject to spurious determination, because of agglutinins (mainly cold), high blood glucose level, natremia, anticoagulants in excess and at times technological considerations. Abnormality related to one measured parameter eventually leads to abnormal calculated RBC indices: mean cell haemoglobin content is certainly the most important RBC parameter to consider, maybe as important as flags generated by the haematology analysers (HA) themselves. In many circumstances, several of the measured parameters from cell blood counts (CBC) may be altered, and the discovery of a spurious change on one parameter frequently means that the validity of other parameters should be considered. Sensitive flags allow now the identification of several spurious counts, but only the most sophisticated HA have optimal flagging, and simpler ones, especially those without any WBC differential scattergram, do not share the same capacity to detect abnormal results. Reticulocytes are integrated into the CBC in many HA, and several situations may lead to abnormal counts, including abnormal gating, interference with intraerythrocytic particles, erythroblastosis or high WBC counts.

Hematology analysers provide now quick, accurate, and reproducible cell blood counts. However, depending on detection methods, spurious counts may occur. If undetected, such spurious counts may lead to inappropriate medical care and to unneeded explorations. Focusing first on platelet counts, situations leading to spurious decrease include several preanalytical considerations, the major one corresponding to EDTA-induced platelet aggregation and to platelet satellitism around polymorphs. In other instances, related to the presence of small particles mimicking platelets, including fragmented red blood cells, lipids, cryoglobulins, fibrin strands, or cytoplasmic fragments of leukocytes, spurious elevation of platelet count may occur. According to the analyser and to the methods used for the determination of the cell blood count, flags or messages related to these spurious changes differ. For each spurious change, the authors describe the mechanism leading to the anomaly, the way the analysers generate flags, and what should be done to provide accurate results.

The French quality control is organized by the French Health Products Safety Agency. In 2005, the immuno-haematology testing control included the screening of an anti KEL 1 antibody. 17 out of 2639 laboratories (0,64%) answered 'negative screening'. All laboratories received a questionnaire in order to understand the failure. In this paper the authors present the detailed laboratories' responses and failure explanations.

In order to take into account the improvement of the knowledge, technologies, automation and computerization in immuno-haematology, the French national regulatory service have redefined the way to complete immunohaematology tests and their links to the blood component distribution. We describe these modalities for each test considering three questions "What?", "When?" and "How?".

The evolution of the methods used in immunohematology is a constant concern for all those involved in the process. Thus, during the last few years, new technologies have been introduced which aim at improving performance. This improvement is not limited to the search for an overall increase in specificity-sensibility; it also takes into account the capability to detect "the clinical significant" as well as the limitations of human reliability, which justifies the introduction of automation and computerization. The whole of these methodological evolutions associated with that of the performance of re-agents, legitimate to modify the law about the realization of erythrocyte typing and detection of irregular antibodies. In order to ensure the immunohematologic safety of transfusions, it was also necessary to place the entire transfusion process under computer control: patient identification, sample collection, test results and release of blood.

The quality tests made during the preparation of labile blood products permit to validate the product and to make sure the making procedures are applied properly. The labile blood products have to correspond to a number of standards set by a ministerial order. It is thus necessary to check the manufacturing unit of some products. On account of the original technology of Cell-Dyn 3500 which associates methods of impedance variation measure analysis and flow cytometric technique analysis on non-marked cells, and of its veterinary modulus permitting counting in extreme values, it seemed to be worth being evaluated in a blood bank quality control laboratory. Linearity was studied from a range of dilutions obtained from high value samples prepared by the centrifugation of blood bags and collection of the buffy coat by Optipress system. The study was performed on 22 samples. The linearity in the counting of red cells, white cells, platelets and haematocrit was measured. Intersample contamination was measured. It focused on the values of platelets and white cells. A sample of high cell concentration prepared in the condition mentioned above and a white cell-reduced blood concentrate were used. The study of repeatability was done by treating 20 times three samples covering a wide range of values of the different parameters of cell numeration. The linearity concerning parameters and the range of the values studied are good (example: from 10 to 3000 10(9)/l for platelets). Contamination is low for white cells and non appreciable for platelets. Repeatability shows excellent variation coefficients.