[State and perspectives of the French haemovigilance system. Presentation of the data collected over 9 years]

[Evaluation of blood grouping in ABO and Rh systems in health facilities in Benin]

STUDY PURPOSE

The goal of this work is to assess the modalities of blood typing achievement in Benin with the view of their improvement.

METHODS

On the basis of a questionnaire including the detailed operative process, a prospective investigation has been achieved in public and private health centers laboratories.

RESULTS

It came out that the execution of ABO and Rh blood typing took place globally on the fringe of the standards. We note that 72.4% of the private laboratories and 48.9% of the public ones lacked at least one equipment and 51.3% at least one material for blood withdrawal; 38.2% of the laboratories did not respect blood withdrawal standards; 1.32% of the laboratories applied the 4×2 rule. The assessment revealed that respectively 10.8% and 30.7% of the blood centers and non-blood centers achieved the globular test solely; the same 40.5% and 46.2% used reagents of different brands. Anti-A1 and anti-H sera, and A1 and A2 red cells were not available in any laboratory. More than 64% of laboratories have senior technicians and biomedical analysis engineers but only 6.6% of the laboratories were directed by biologists, and 9.2% of the laboratories function with only one technician.

CONCLUSION

Instead of some assets, the laboratories assessment noted important non-conformities we ought to raise as a matter of urgency. It is a challenge whose resolution must give blood transfusion centers a reference position relatively to blood grouping when facing blood typing difficulties.

[Pathogen reduction of blood components: from financial issues to possible long-term consequences]

Pathogen inactivation of blood products represents a global and major paradigm shift in transfusion medicine. In the next near future, it is likely that most blood products will be inactivated by various physicochemical approaches. The concept of blood safety will be challenged as well as transfusion medicine practice, notably for donor selection or biological qualification. In this context, it seems mandatory to develop analytical economic approaches by assessing costs-benefits ratio of blood transfusion as well as to set up cohorts of patients based on hemovigilance networks allowing rigorous scientific analysis of the benefits and the risks of blood transfusion at short- and long-term.

[Red blood cell antibody screening: error analysis in a french interlaboratory comparison program survey]

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.

Residual risk of transfusion-transmitted human immunodeficiency virus, hepatitis C virus, and hepatitis B virus infections in Italy

BACKGROUND

Estimating the risk of transfusion-transmitted infections (TTIs) is essential for monitoring blood safety. The residual risk of TTI was estimated for nearly 90 percent of the blood supply in Italy.

STUDY DESIGN AND METHODS

Data were analyzed from 1,079,281 repeat donors, corresponding to 5,361,000 donations made in blood transfusion centers throughout Italy in the period 1999 through 2001. The residual risk of transfusion-transmitted human immunodeficiency virus (HIV), hepatitis C virus (HCV), and hepatitis B virus (HBV) infections was estimated with the incidence rate-window period model. The denominator for the incidence rate (i.e., the number of person-years at risk) was estimated on a sample of 5850 donors.

RESULTS

The risk of an infectious donation entering the blood supply, per 1 million donations, was 1.91 (probable range, 0.52-3.32) for HIV, 16.74 (9.57-24.01) for HCV, and 69.16 (43.12-102.70) for total HBV (adjusted for vaccination and hepatitis B surface antigen transience).

CONCLUSION

In Italy, the estimated residual risk of TTI is apparently low, particularly for HIV infection. Although the estimated risks are higher for HCV and HBV, the introduction of mandatory viral detection tests for HCV in 2002 should account for an 80 percent reduction in the HCV risk. Moreover, the ongoing HBV vaccination program will contribute to reducing the risk of transfusion-transmitted HBV.

[Cellular mechanisms implicated in anti-erythrocyte alloimmunization]

In many clinical situations patients are dependent on blood transfusions. Occurrence of alloimmunization to blood group antigens (BGA) complicates the transfusion strategy and may be involved in clinical transfusion stalemate situations. B cell differentiation into antibody-secreting plasma cells is triggered by antigen and requires helper T cells which produce cytokines. Although antibodies implicated in BGA alloimmunization have been studied for many years, little is known about helper T cell responses that drive their production. Few studies on BGA specific T cell responses have been published today. This review summarizes the new developments in the field of cellular mechanisms implicated into antibody production. The definition of immunodominant peptides derived from RhD and Jk(a) BGAs, the cytokine patterns induced and the HLA class II molecules implicated in their presentation are analyzed. A tolerogenic route for RhD immunodominant peptides is experimented. Identification of such immunodominant peptides, the cytokine patterns induced and the HLA class II molecules implicated in their presentation, would facilitate the design of new therapeutic strategies including the specific control of alloimmunization with peptide antigen tolerogens or the ex-vivo induction of regulatory T cells.

Haemovigilance in a general university hospital: need for a more comprehensive classification and a codification of transfusion-related events

BACKGROUND AND OBJECTIVES

The purpose of this study was to analyse the transfusion-related events recorded in a general university hospital.

MATERIALS AND METHODS

The method we used was retrospective analysis of the data collected between 1999 and 2003.

RESULTS

The incidence of transfusion reactions (n = 394) was 4.19 per 1000 blood products distributed: 59% (n = 231) were febrile non-haemolytic transfusion reactions; 22% (n = 88) were caused by allergy; 5% (n = 21) were caused by bacterial infection; and 14% (n = 54) were classified as other reactions. Platelet concentrates gave rise to a significantly greater number of reactions than erythrocyte concentrates and fresh-frozen plasma. Transfusion errors and near-miss events were also observed and were analysed separately. A series of transfusion-related events, such as haemosiderosis, metabolic disturbances or volume overload, were not reported.

CONCLUSIONS

Our experience prompts us to propose a more comprehensive classification and codification of transfusion-related events.

La responsabilité du médecin prescripteur de produits sanguins labiles

Blood transfusion presents mainly virological, bacteriological, immunohaematological and volemic risks; with the latter two particularly concerning health establishment employees. This article tackles the physician's responsibility in blood transfusion. Taking into account the regulations that surround the activity, prescribing physicians must know and put into action the relative requirements in their practises in order to avoid taking on its responsibility, or that of the health establishment in which they work, as any lack of respect for the rules and regulations could result in being held liable for any side affects suffered by the patient. The article has the objective of identifying the main regulation requirements in order to control them despite a difficult environment, from the point of view of patients' rights regarding the benefits and the consequences of transfusion. These requirements focus mainly on information and patient consent, the prescription of blood products as well post transfusion information and the follow-up care. Proof of respect for these rule requirements must be available for each of these aspects.