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Despite the generalization of immunoprophylaxis by anti-RH immunoglobulins over 40 years, fetomaternal incompatibility due to RH1 antigen (RhD) is not completely eradicated, although perinatal consequences might be extremely serious. Additionally, allo-immunizations against other antigens, especially anti-RH4 (anti-c) and anti-KEL1 (anti-Kell), may cause severe haemolytic disease. Follow-up of allo-immunization during pregnancy and its prevention are therefore still a concern for all pregnant women. Immunohaematological tests used in antenatal patients are under practice for a long time. However, despite significant progress, it is clear that these tests provide only an indirect indication and will only help the obstetrician, in conjunction with over fetal parameters, to assess the severity of the haemolytic disease. Since almost two decades, fetal RHD genotyping became a reality, first using amniocytes, but more recently by analyzing fetal DNA present in the maternal plasma. RH prophylaxis concerns RH:-1 women, who are non-sensitized against RH1 antigen during and at the end of their pregnancy with a RH1 child. RH prophylaxis includes targeted prophylaxis after foetomaternal haemorrhage and now routine antenatal RH prophylaxis at 28 gestation weeks. Indications for RH prophylaxis and immunohaematological testing to assure an efficient therapeutic prevention have been summarized in France through specific recommendations of the National College of Gynecologists and Obstetricians.

According to requirements of the French Committee for Accreditation (Cofrac), it is essential to use validated and standardised methods in Immunohematology. This imposes first the knowledge of metrological tolerances for all the technics. Two multicenter studies were carried out to define the maximal acceptable deviations concerning incubation temperature and time, volumes of patient plasma and tests cells for antibody screening using indirect antiglobulin test on one hand and for reverse grouping on another hand. All equipment used (temperature test chamber, chronometer, pipettes) were calibrated according to Cofrac standards. The antibody screenings were performed manually using 3 different filtration systems: ID Diamed, Biovue Ortho and Scangel Biorad, the same tests cells, a standard 20 ng/mL anti RH1, a positive control anti KEL1 and a negative control; the reverse blood grouping was performed manually using the above mentionned filtration systems and microplate technic with the same A1 and B test cells. These two studies showed that all the tests from the multiples combinations of the above parameters gave the same results and allowed us to define a range of tolerance for 4 critical physical parameters involved in the antibody screening and blood typing.

Resume Lors de l'operation de 2005 du Controle national de qualite portant sur les RAI, 17 laboratoires sur les 2639 participants ont rendu un depistage faussement negatif. Un questionnaire a ete adresse aux laboratoires concernes afin de determiner la cause de leur erreur. L'analyse de ce questionnaire a fait apparaitre, outre la forte implication des biologistes dans la demarche de qualite, la preponderance d'erreurs non analytiques telles que des erreurs d'echantillon, de transcription et de saisie informatique. Le questionnaire a permis par ailleurs de recueillir des informations sur la pratique des laboratoires et sur les mesures correctives entreprises.

Resume Les tests immunohematologiques utilises pour le depistage des incompatibilites fœto-maternelles ont beaucoup evolue. Toutefois, malgre les progres accomplis, ces tests ne font qu'aider l'obstetricien a evaluer, avec l'aide d'autres parametres fœtaux, la severite de la maladie hemolytique du nouveau-ne ou du fœtus. La meilleure methode pour evaluer cette gravite reste la determination directe de l'hemoglobine fœtale apres prelevement de sang fœtal mais cet examen n'est pas sans risque. Depuis 10 ans, il est possible de determiner par biologie moleculaire le genotype RHD fœtal a partir du DNA extrait des cellules amniotiques, et aujourd'hui directement a partir du plasma maternel. Toute femme enceinte doit faire l'objet d'une double determination du groupe sanguin ABO-RH1 et du phenotype RH-KEL1 et de recherches d'anticorps anti-erythrocytaires (RAI). En cas de presence d'allo-anticorps, l'evolution du taux doit etre realisee par titrage en test indirect a l'antiglobuline associe au dosae ponderal (pour les anti-RH, qui restent les plus frequents). Ce dernier test, mesurant par methode semi-quantitative et automatisee la concentration en anticorps, est plus performant et reproductible que le test indirect a l'antiglobuline manuel.

Resume L’evolution des methodes utilisees en immunohematologie est un souci constant des differents intervenants. Au cours des dernieres annees de nouvelles technologies ont fait leur apparition en vue d’ameliorer les performances. Cette amelioration ne se limite pas a la recherche d’un accroissement global de la specificite–sensibilite ; elle tient compte egalement de la capacite de detection du « cliniquement significatif » et des limites de la fiabilite humaine, justifiant l’automatisation et l'informatisation. Ces evolutions methodologiques ainsi que celles des performances des reactifs justifient une modification de la loi relative a la realisation des typages erythrocytaires et des detections d’anticorps anti-erythrocytaires. Pour garantir la securite immunohematologique des transfusions, il est necessaire de placer la totalite du processus sous controle informatique : identification du patient, distribution de l'echantillon, lecture et transfert des resultats et delivrance des produits sanguins labiles.

Detection and identification of irregular red-cell antibody in the serum or plasma of a patient is of prime importance for the prevention of hemolytic transfusion reactions and the biological supervision of the hemolytic disease of the foetus or the newborn. Practice in these tests is replete with complex biological problems. Using problem solving strategies, we discuss the recognition and resolution of the most frequent difficulties encountered in red cell antibody identification.

Summary In a transfusional or fœto-maternal context, hemolysis by incompatibility due to anti-erythrocyte antibodies (regular or irregular) remains the most frequent and most serious immunological risk in the receiver. In order to prevent this risk, a number of actions must be taken, such as the realization of the immunohematologic analyses for which the methodological practices have been legislated because of their serious clinical consequences. Several elements play a role in the reliability of the analyses and their results: the selection of the reagents and their validation in the routine technique used; the validation of reception; the controls involved in secondary preparations (e.g., blood cells reagent); and the daily internal controls. All this requires the choice of adapted controls and the management of possible anomalies.

The immunogenic nature of erythrocyte polymorphism is in variance with the incompatible transfusion. Indeed, the fixing of an antibody on the corresponding antigen generally condemns the cell concerned with its destruction. Therefore, in order to ensure the immunohemolytic safety of the transfusions, it is necessary to avoid an in vivo encounter between antigens and antibodies, whose feasibility study in vitro is a determining element. Because of the requirement standards of such analyses and the preoccupation with the continuous improvement of transfusion safety, 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 and sometimes implementing alternatives to agglutination. This improvement is not limited to the search for an overall increase in specificity-sensitivity; it also takes into account the capability to detect "the clinically 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 reagents, legitimate the need to reconsider the realization of erythrocyte typing and the search for anti-erythrocyte antibodies.

Practice in immunohematology is replete with complex problems that require practitioners' problem-solving performance. In immunohematology, the acquisition of the reasoning process and necessary skills for making clinical decisions is based on teaching problem-solving strategies which potentially reduce errors and improve patient outcome. We discuss the recognition and resolution of the common causes of discrepancies in ABO typing results using problem-solving strategies.

The detection of irregular antibodies is usually performed with serum by the indirect antiglobulin test (IAT) with a polyspecific antiglobulin reagent. In a first study in 1996, we compared the results obtained with 3,264 blood samples of patients drawn with or without anticoagulant: no significant difference was observed among the 240 allo-antibodies detected and identified. In this paper we report the comparison of the results obtained by IAT on column of filtration with two kinds of reagents: polyspecific and anti-IgG antibodies. Respectively 2,927 (76 contained an antibody), and 643 (161 contained an antibody) sera of patients were tested with methods ID-Diamed and Ortho-Biovue. Titrations of 153 other antibodies were also performed with the two reagents. Results showed no significant difference using either polyspecific reagent or the anti-IgG antibodies. This study proves that it is possible to perform screening of irregular antibodies on uncoagulated blood samples. This possibility allows automation as blood typing and screening of irregular antibodies can be carried out with the same sample.

Resume Deux controles de qualite 96-01 et 97-02 ont ete organises par l'etablissement de transfusion sanguine du Nord-Pas-de-Calais (site de Lille) dans le cadre de l'activite du groupe Immunohematologie de la Societe francaise de transfusion sanguine et proposes aux etablissements de transfusion sanguine francais (ETS). Leur but etait d'evaluer les performances d'identification d'allo-anticorps masques par un auto-anticorps dirige contre un antigene de frequence elevee. Concernant le controle 96-01, 110 ETS ont participe a ce controle de qualite, 83 (soit 75 %) ont adresse une reponse ecrite, 78 (soit 94 %) ont donne un resultat correct quant au depistage des allo-anticorps et 61 (soit 78 %) un resultat correct d'identification (anti-RHl + FY1). Concernant le controle 97-02, 87 ETS ont participe a ce controle de qualite, 82 (soit 94 %) ont adresse une reponse ecrite, 69 (soit 88 %) ont donne un resultat correct quant au depistage des allo-anticorps et 53 (soit 77 %) un resultat correct d'identification (anti-RH3 + FY1). L'etude des reponses a permis de preciser les techniques d'elimination des auto-anticorps. Les resultats de ces controles de qualite ont confirme leur interet pour l'appreciation, d'une part, de la qualite de la realisation de ces examens et, d'autre part, des moyens a mettre en œuvre pour en ameliorer les performances.

Resume La transfusion sanguine presente essentiellement des risques immunologiques et infectieux. Le risque immunologique est lie a une incompatibilite entre le sang du donneur et celui du receveur ; ce risque demeure mal evalue. Une etude multicentrique a ete realisee par la Societe Francaise de Transfusion Sanguine et l'Institut National de la Transfusion Sanguine qui a permis de recenser 61 accidents lies a une incompatibilite erythrocytaire : 26 cas concernaient une incompatibilite ABO, 35 cas une incompatibilite par alloanticorps de systemes autres que ceux du systeme ABO. Pour la premiere categorie d'accidents, l'anomalie la plus frequente est le non respect du controle ultime au lit du malade. Pour les accidents associes aux alloanticorps des systemes immunogenes, le probleme majeur est celui de la realisation et surtout de l'interpretation de la recherche d'agglutinines irregulieres. Le suivi a long terme montre qu'il n'y a pas de sequelle chronique des accidents immunologiques. Pour l'ensemble des accidents, les modes de defaillances ont ete identifies et analyses, faisant apparaitre que le fait generateur d'accidents se situe actuellement au niveau des etablissements de soins.

The Societe Francaise de Transfusion Sanguine and the Centre National de Reference pour les Groupes Sanguins performed a quality control to evaluate the performances of two serological tests: the Direct Antiglobulin Test (DAT) and the Elution test. Among the 110 Blood Transfusion Centers participating in this control, 80 (73%) returned a result. Of these, 68 results were correct for the DAT (85%; positive for type IgG) and 31 results were correct for the elution (39%; anti-FY1). This control gave the opportunity to confirm the main procedures used in routine testing on a national scale. The analysis of the results underlines the importance of the choice of a standardized technique for these tests. Such controls are useful to appreciate the quality of the routine tests and to find the means to improve them.

Alloimmunization to red cell antigens and haemolytic transfusion reactions may occur after red blood cell transfusion. We describe a case of life threatening postransfusion hyperhaemolysis in a beta thalassaemia patient. For many years, transfusion therapy was stopped but the patient developed a profound anaemia which required splenectomy. At that time, the serum contained a red cell alloantibody with anti-KN3 specificity. In vivo red cell survival studies were performed trying to determine the capacity of this antibody to cause red cell destruction. Unfortunately, these studies triggered again an intense haemolytic process explained by the appearance of red cell auto- and alloantibodies. This case underlines a possible link between the development of alloimmunization and the induction of potentially serious autoimmune haemolytic anaemia.

Vascular endothelial cells are suspected of being the target of autoimmune processes seen in many connective tissue diseases and in systemic vasculitis as evidenced by the detection of circulating autoantibodies against endothelial cell antigens. In order to select B cells recognizing endothelial cells antigens, Epstein-Barr virus (EBV)-infected B cells, obtained from one patient presenting a systemic vasculitis, were cocultured with human endothelial cells concurrently with a human endothelial cell line (EC-pSV1 cells). This coculture consisted of a first step of expansion of B cells specifically selected by adherence onto human umbilical vein endothelial cells (HUVEC). The adherence of selected B cells was specific to endothelial cells because no rosette formation around control cells (HeLa cells or COS cells) was observed. Adherent B cells were cloned by limiting dilution by coculture onto EC-pSV1 cells and screened for anti-HUVEC antibody production by endothelial cell ELISA. An increase in anti-HUVEC antibody production of IgM isotype was detected by endothelial cell ELISA, peaking at Day 9 and remaining constantly elevated, relative to B cell expansion. Among 21 B cell lines producing IgM, 6 presented high levels of anti-HUVEC antibodies, whereas 1 of 52 B cells cloned without EC-pSV1 cells showed such antibody production. Anti-HUVEC antibody production and B cell proliferation were dependent on the presence of endothelial cells. Two of these 6 B cell lines produced antibodies directed against an endothelial cell antigen with an apparent molecular weight of 192 kDa as determined by immunoblotting analysis. Our results demonstrate that adherence of EBV-infected B cells to endothelial cells and further cloning by adherence can efficiently select anti-HUVEC antibody-producing human B cells and might help to define antigens potentially involved in autoimmune diseases.

Cross-matching between the serum of a patient and the red blood cells to be transfused is most important for the prevention of hemolytic transfusion reactions in allo-immunized or new-born patients found positive with direct antiglobulin test. Cross-matching is a time-consuming and complex laboratory test. In order to obtain valid results, it is necessary to abide by some technical rules detailed in this article. The choice of the blood units to be cross-matched depends on the patient's clinical story and on the specificity of anti-erythrocyte antibodies present in the serum. The identification and the management of most frequent difficulties met by using the cross-match technique are discussed hereby.

This study reports the results of ABO-Rh (D) typing in microplate according to a suggested protocol. 35,532 blood typings were performed by 13 laboratories, compared to usual technics. This work has proved the feasibility in routine of this protocol in order to identify the A, B, D and weak antigens. However the difficulties in detecting some weak variants reveal the interest of standards for immuno-haematology reagents, to apply in the microplate technology.

Despite the generalization of immunoprophylaxis by anti-RH immunoglobulins over 40 years, fetomaternal incompatibility due to RH1 antigen (RhD) is not completely eradicated, although perinatal consequences might be extremely serious. Additionally, allo-immunizations against other antigens, especially anti-RH4 (anti-c) and anti-KEL1 (anti-Kell), may cause severe haemolytic disease. Follow-up of allo-immunization during pregnancy and its prevention are therefore still a concern for all pregnant women. Immunohaematological tests used in antenatal patients are under practice for a long time. However, despite significant progress, it is clear that these tests provide only an indirect indication and will only help the obstetrician, in conjunction with over fetal parameters, to assess the severity of the haemolytic disease. Since almost two decades, fetal RHD genotyping became a reality, first using amniocytes, but more recently by analyzing fetal DNA present in the maternal plasma. RH prophylaxis concerns RH:-1 women, who are non-sensitized against RH1 antigen during and at the end of their pregnancy with a RH1 child. RH prophylaxis includes targeted prophylaxis after foetomaternal haemorrhage and now routine antenatal RH prophylaxis at 28 gestation weeks. Indications for RH prophylaxis and immunohaematological testing to assure an efficient therapeutic prevention have been summarized in France through specific recommendations of the National College of Gynecologists and Obstetricians.

Resume Des lymphocytes circulants provenant d'une femme multipare immunisee aux antigenes C et Ce ont ete recoltes 14 jours apres son dernier accouchement. Apres heterohybridation, une lignee a produit un anticorps monoclonal humain de nature IgM. La caracterisation serologique de l'anticorps a ete realisee en saline et par techniques enzymatiques vis-a-vis d'un panel incluant des hematies de phenotype rare. Elle a montre qu'il s'agissait d'un anticorps puissant reagissant directement en milieu salin avec toutes les hematies C positif provenant de sujets Ce positif et Ce negatif. La validation a ete effectuee manuellement (tube) et de facon semi-automatisee (en microplaque) sur 2 500 prelevements de receveurs. Aucune discordance n'a ete constatee. Au vu de ces resultats : specificite, activite et caracteristiques serologiques, cet anticorps monoclonal a ete utilise a des fins diagnostiques. Depuis 1 an, plus de 30 000 phenotypages ont ete realises sur le sang des receveurs et des femmes enceintes dans d'excellentes conditions.

Further to a survey set up in 2006 over 2600 laboratories by the French agency for health product safety (AFSSAPS), seven ABO grouping errors and 53 negative answers to red blood cell antibody screening with a serum containing anti-RH1 antibody, have been found. A questionnaire sent to the involved laboratories revealed non-analytical errors already met in previous cases. Besides, the analytical stage has also induced red blood cell antibody screening errors due to a wrong serum collection by the automat. Here are displayed the analysis of the questionnaire results and proposed corrections.

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.

Background and objectives: Many drugs are associated with thrombocytopenic purpura through immune-mediated platelet destruction. The case of a woman who suffered lifethreatening thrombocytopenia during vancomycin treatment for Staphylococcus aureus septicemia is reported. Materials and methods: Conventional clinical and laboratory methods, including flow cytometry. Results: After treatment of septicemia with vancomycin, severe thrombocytopenia and bleeding occurred, without detection of drug-dependent platelet antibodies (DDPA). This was followed by vegetative endocarditis, whereupon antibiotics were withdrawn so as to isolate the organism. The thrombocytopenia was corrected. On day 34, antibiotics including vancomycin were reinstituted, and three days later thrombocytopenia recurred. With a change in antibiotics, the platelet count corrected itself within four days. Conclusions: Vancomycin may induce potentially severe immunological thrombocytopenia.

According to requirements of the French Committee for Accreditation (Cofrac), it is essential to use validated and standardised methods in Immunohematology. This imposes first the knowledge of metrological tolerances for all the technics. Two multicenter studies were carried out to define the maximal acceptable deviations concerning incubation temperature and time, volumes of patient plasma and tests cells for antibody screening using indirect antiglobulin test on one hand and for reverse grouping on another hand. All equipment used (temperature test chamber, chronometer, pipettes) were calibrated according to Cofrac standards. The antibody screenings were performed manually using 3 different filtration systems: ID Diamed, Biovue Ortho and Scangel Biorad, the same tests cells, a standard 20 ng/mL anti RH1, a positive control anti KEL1 and a negative control; the reverse blood grouping was performed manually using the above mentionned filtration systems and microplate technic with the same A1 and B test cells. These two studies showed that all the tests from the multiples combinations of the above parameters gave the same results and allowed us to define a range of tolerance for 4 critical physical parameters involved in the antibody screening and blood typing.

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.

Immunohaematological tests used in antenatal patients have come a long way. However, despite a great deal of progress, we should not loose sight of the fact that these tests give only an indirect measurement and will only help the obstetrician, in conjunction with other fetal parameters, to assess the severity of the haemolytic disease (HD) of the fetus and newborn. The best method to assess the severity is the direct determination of foetal blood group hemoglobin after foetal blood sampling but this procedure is not without risk. Since 10 years ago, it is possible to determine the RHD genotype of the fetus using amniocytes and, today, maternal plasma directly. All pregnant women should be grouped for ABO-RH-KEL1 and the sera tested for clinically irregular antibodies (anti-RH are still the most frequent). The trend in anti-RH levels is more important than the level itself. The perfect technique for anti-RH quantitation has not been developed. Manual titration is simple but only provides rough, semiquantitatives estimates of anti-RH concentration. Quantitative haemagglutination methods, using auto-analyzers and appropriate anti-RH1 standards, measure in microg/ml, are sensitive, rapid and have acceptable intra-laboratory reproductibility.

Cross-matching between the serum of a patient and the red blood cells to be transfused is most important for the prevention of hemolytic transfusion reactions in allo-immunized or new-born patients found positive with direct antiglobulin test. Cross-matching is a time-consuming and complex laboratory test. In order to obtain valid results, it is necessary to abide by some technical rules detailed in this article. The choice of the blood units to be cross-matched depends on the patient's clinical story and on the specificity of anti-erythrocyte antibodies present in the serum. The identification and the management of most frequent difficulties met by using the cross-match technique are discussed hereby.

In spite of the progress made since 1970 in specific prevention by anti-rhesus immunoglobulins, and improved management of at-risk pregnancies, allo-immunization due to the erythrocytic Rh 1 antigen (formerly known as Rhesus D or Rh D) remains widespread. In fact, anti-Rh 1 antibodies currently constitute over one-third of the immune antibodies detected after pregnancy. The prevention of allo-immunization against the Rh 1 antigen is therefore still problematical, and concerns approximately one pregnant woman in seven. The etiology and pathology of fetal hemolytic disease have been recalled, and the treatment approach during pregnancy and delivery has been carefully examined. Tests for quantifying the risk of fetomaternal hemorrhage have also been described. This approach aims at improving the methods of preventing allo-immunization (e.g., during pregnancy and delivery) and the efficacy of treatment. It is also stated that if the necessary preventive action is not taken in cases of allo-immunization due to to the Rh 1 antigen, this should be considered a grave medical fault.

Detection and identification of irregular red-cell antibody in the serum or plasma of a patient is of prime importance for the prevention of hemolytic transfusion reactions and the biological supervision of the hemolytic disease of the foetus or the newborn. Practice in these tests is replete with complex biological problems. Using problem solving strategies, we discuss the recognition and resolution of the most frequent difficulties encountered in red cell antibody identification.

In a transfusional or foeto-maternal context, hemolysis by incompatibility due to anti-erythrocyte antibodies (regular or irregular) remains the most frequent and most serious immunological risk in the receiver. In order to prevent this risk, a number of actions must be taken, such as the realization of the immunohematologic analyses for which the methodological practices have been legislated because of their serious clinical consequences. Several elements play a role in the reliability of the analyses and their results: the selection of the reagents and their validation in the routine technique used; the validation of reception; the controls involved in secondary preparations (e.g., blood cells reagent); and the daily internal controls. All this requires the choice of adapted controls and the management of possible anomalies.

The immunogenic nature of erythrocyte polymorphism is in variance with the incompatible transfusion. Indeed, the fixing of an antibody on the corresponding antigen generally condemns the cell concerned with its destruction. Therefore, in order to ensure the immunohemolytic safety of the transfusions, it is necessary to avoid an in vivo encounter between antigens and antibodies, whose feasibility study in vitro is a determining element. Because of the requirement standards of such analyses and the preoccupation with the continuous improvement of transfusion safety, 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 and sometimes implementing alternatives to agglutination. This improvement is not limited to the search for an overall increase in specificity-sensitivity; it also takes into account the capability to detect "the clinically 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 reagents, legitimate the need to reconsider the realization of erythrocyte typing and the search for anti-erythrocyte antibodies.

Practice in immunohematology is replete with complex problems that require practitioners' problem-solving performance. In immunohematology, the acquisition of the reasoning process and necessary skills for making clinical decisions is based on teaching problem-solving strategies which potentially reduce errors and improve patient outcome. We discuss the recognition and resolution of the common causes of discrepancies in ABO typing results using problem-solving strategies.

The detection of irregular antibodies is usually performed with serum by the indirect antiglobulin test (IAT) with a polyspecific antiglobulin reagent. In a first study in 1996, we compared the results obtained with 3,264 blood samples of patients drawn with or without anticoagulant: no significant difference was observed among the 240 allo-antibodies detected and identified. In this paper we report the comparison of the results obtained by IAT on column of filtration with two kinds of reagents: polyspecific and anti-IgG antibodies. Respectively 2,927 (76 contained an antibody), and 643 (161 contained an antibody) sera of patients were tested with methods ID-Diamed and Ortho-Biovue. Titrations of 153 other antibodies were also performed with the two reagents. Results showed no significant difference using either polyspecific reagent or the anti-IgG antibodies. This study proves that it is possible to perform screening of irregular antibodies on uncoagulated blood samples. This possibility allows automation as blood typing and screening of irregular antibodies can be carried out with the same sample.

The French Blood Transfusion Society working group Immunohaematology and the French Blood Transfusion Center of Lille performed two quality control exercises-96-01 and 97-02-in order to evaluate identification performances of alloantibodies associated with an autoantibody recognizing a high frequency antigen. Concerning control 96-01, 83 (75%) of the 110 blood transfusion centers participating at this exercise sent results. The alloantibody screening was correct for 78 of them (94%). Sixty-one (78%) blood transfusion centers correctly identified the specificities (anti-RH1 + anti-FY1). Concerning control 97-02, 82 (94%) of the 87 blood transfusion centers participating in this exercise sent results. The alloantibody screening was correct for 69 (88%) of them. Fifty-three blood transfusion centers (77%) correctly identified the specificities (anti-RH3 + anti-FY1). These exercises allowed us to confirm the main procedures used in routine for national scale testing. The analysis of the results has underlined the importance of these tests for assessing the quality of these examinations, and highlighted the means to be carried out in order to improve them.

Prenatal diagnosis of genetic abnormalities requires nucleated fetal cells which are currently obtained by invasive techniques such as amniocentesis, chorionic villus sampling and percutaneous umbilical blood sampling. Each of these entails a risk to the foetus and sometimes to the mother. Nucleated fetal cells have been reported to be present in maternal blood. Recovery of fetal cells from maternal blood would allow a noninvasive prenatal diagnosis. Their rarity (1 fetal cell for 10(6) to 10(8) maternal cells) presents a technical challenge. Due to the small number of fetal cells, sensitive analysis techniques such as PCR and FISH are necessary. Some degree of fetal cells enrichment in the maternal blood sample often precedes the analysis. Different techniques are used for the enrichment: discontinuous density gradient, magnetic activated cell sorting, fluorescence activated cell sorting, micromanipulator.... Several prenatal diagnosis have already been performed from maternal venous blood samples: diagnosis of gender, RhD blood genotype, Duchenne muscular dystrophy and hemoglobinopathy by PCR, diagnosis of gender and chromosome aneuploidy by FISH. Many teams are working on this subject. It is difficult to compare the studies because the techniques of enrichment and analysis vary. We review the different strategies chosen for prenatal diagnosis from maternal blood and discuss the results.

For ten years, the working party of immunohaematology of the French Society of Blood Transfusion organizes a quality control. After the modification of the law about the realization of erythrocyte typing and detection of unexpected red cell allo-antibodies, the quality control was performed in order to determine the sensitivity of the indirect antiglobulin test by filtration with a standard anti-RH1(D) produces by the National Reference Center of Blood Groups.

The Société Française de Transfusion Sanguine and the Centre National de Référence pour les Groupes Sanguins performed a quality control to evaluate the performances of two serological tests: the Direct Antiglobulin Test (DAT) and the Elution test. Among the 110 Blood Transfusion Centers participating in this control, 80 (73%) returned a result. Of these, 68 results were correct for the DAT (85%; positive for type IgG) and 31 results were correct for the elution (39%; anti-FY1). This control gave the opportunity to confirm the main procedures used in routine testing on a national scale. The analysis of the results underlines the importance of the choice of a standardized technique for these tests. Such controls are useful to appreciate the quality of the routine tests and to find the means to improve them.

Blood transfusion is mainly bound to immunological and infectious risks. The immunological risk originates from an incompatibility between the blood of the donor and that of the recipient; this risk remains insufficiently assessed. A multicentre study has been carried out by the French Blood Transfusion Society and the National Institute for Blood Transfusion. Sixty-one accidents due to an erythrocyte incompatibility were found: 26 cases with ABO incompatibility, and 35 cases with alloantibodies of other blood group systems. For the former category of accidents, the most frequent cause was due to a failure in the realization of the bedside ABO check. For the latter, the main problem was the achievement and the interpretation of antibody screening. The long term follow-up shows no chronic after-effects of immunological accidents. For each accident, errors have been identified and analysed. It was proven that they all originate from health care establishments.

Alloimmunization to red cell antigens and haemolytic transfusion reactions may occur after red blood cell transfusion. We describe a case of life threatening postransfusion hyperhaemolysis in a beta thalassaemia patient. For many years, transfusion therapy was stopped but the patient developed a profound anaemia which required splenectomy. At that time, the serum contained a red cell alloantibody with anti-KN3 specificity. In vivo red cell survival studies were performed trying to determine the capacity of this antibody to cause red cell destruction. Unfortunately, these studies triggered again an intense haemolytic process explained by the appearance of red cell auto- and alloantibodies. This case underlines a possible link between the development of alloimmunization and the induction of potentially serious autoimmune haemolytic anaemia.