[Immunohematological surveillance of the pregnant woman: new prevention policy]. / Suivi immunohématologique des femmes enceintes: nouvelles recommandations.

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.

[ABO-RH1 grouping and red blood cell antibody screening: error analysis in the French external quality assessment in 2006]. / Groupes sanguins et recherche des anticorps antiérythrocytaires: analyse d'erreurs au contrôle national de qualité en 2006.

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.

[Red blood cell antibody screening: error analysis in a french interlaboratory comparison program survey]. / Recherche des anticorps antiérythrocytaires: analyse d'erreurs au Contrôle national de qualité

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.

[Validation of antibody screening by indirect antigloblin test and ABO blood typing by filtration and microplate techniques: assessment of robustness]. / Maîtrise des tolérances métrologiques : application à la recherche des anticorps anti-érythrocytaires (RAI) en test indirect à l'antiglobuline (TIA) et au groupage sanguin ABO par les procédés de filtration et en microplaque.

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.

[Quality control: sensitivity of the indirect antiglobulin test by filtration]. / Evaluation externe de la qualité: étude de la sensibilité du procédé de filtration en test indirect à l'antiglobuline.

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.

[Critical analysis of the new ministerial order about guidelines in immunohaematology]. / Nouvel arrêté de bonnes pratiques d'immunohématologie: analyse critique.

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.

[Follow-up of the feto-maternal allo-immunization]. / Suivi de l'allo-immunisation foeto-maternelle.

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.

[External quality evaluation]. / Evaluation externe de la qualité.

Since ten years, the immunohaematology working group of the French Society of Blood Transfusion has organized a quality control. Tests concern essentially the screening and identification of irregular antibodies, direct antiglobulin tests and elutions.