[Immunologic risk analysis of blood transfusion: 1991-1998]

Traceability of Blood Transfusions and Reporting of Adverse Reactions in Developing Countries: A Six-Year Postpilot Phase Experience in Burkina Faso

Traceability is an essential tool for haemovigilance and transfusion safety. In Burkina Faso, the implementation of haemovigilance has been achieved as part of a pilot project from 2005 to 2009. Our study aims to evaluate the traceability of blood transfusions and reporting of adverse reactions over the 6-year postpilot phase. A cross-sectional study including all blood units ordered between 2010 and 2015 has been conducted in public and private health care facilities supplied with blood products by the transfusion center of Bobo-Dioulasso. The complete traceability was possible for 83.5% of blood units delivered. Adverse reactions were reported in 107 cases representing 2.1/1,000 blood units per annum. Transfusions of wrong blood to wrong patient were reported in 13 cases. Our study shows that the haemovigilance system in Burkina Faso must be improved. Healthcare workers have to be sensitized on how traceability and haemovigilance could impact the quality of care provided to patients.

The Incidence Rate of Acute Transfusion Reactions in Thalassemia Patients Referred to the Shiraz Thalassemia Centre, Shiraz, Iran, Before and After the Establishment of the Hemovigilance System

This study aimed to investigate the incidence rate of acute transfusion reactions in thalassemia patients before and after the establishment of the hemovigilance system. This prospective descriptive study was conducted at the Dastgheyb Hospital, Shiraz, Iran, from 2009 to 2012. The incidence rate, type, imputability and severity of acute transfusion reactions were compared in thalassemia patients before and after the establishment of the hemovigilance system. A total of 741 thalassemia patients were referred to the Dastgheyb Hospital for transfusions during the study period. The incidence rates of acute transfusion reactions were reported as 0.06% (11 out of 16,214), 0.11% (23 out of 19,660), 0.10% (28 out of 26,129) and 0.2% (50 out of 24,121), respectively, from 2009 to 2012. The most frequent were major allergic reactions and febrile non hemolytic transfusion reactions (FNHTR). The transfusion reactions were increasingly reported after the establishment of the hemovigilance system in 2011 (p < 0.05). The establishment of the hemovigilance system can improve reporting of transfusion reactions. Moreover, evaluation of the incidence rate of transfusion reactions is necessary to design preventive measures to reduce transfusion risks.

[Delayed haemolytic transfusion reaction due to anti-JK1 antibody]

INTRODUCTION

The sensitivity of the detection of irregular antibodies (DIA) is one of the fundamental basis of transfusion safety. The production of alloantibodies is the first cause of adverse events following transfusion.

CASE REPORT

We report a 77-year-old woman who was transfused and presented with a delayed haemolytic anemia due to anti-JK1 alloimmunization. This event highlights the limits of DIA performed before a transfusion, the hazard of this specific type of antibody and the difficulties of the diagnosis of haemolytic anaemia. The preventive measures necessary to avoid this undesirable effect are reminded.

CONCLUSION

Despite the sensitive routine test method, the anti-JK1 antibodies could be missed. We should keep in mind the possibility of an anaemia due to alloantibodies we confronted to an unexplained haemolytic episode.

Evaluation of Four Bedside Test Systems for Card Performance, Handling and Safety

SUMMARY: OBJECTIVE: Pretransfusion ABO compatibility testing is a simple and required precaution against ABO-incompatible transfusion, which is one of the greatest threats in transfusion medicine. While distinct agglutination is most important for correct test interpretation, protection against infectious diseases and ease of handling are crucial for accurate test performance. Therefore, the aim of this study was to evaluate differences in test card design, handling, and user safety. DESIGN: Four different bedside test cards with pre-applied antibodies were evaluated by 100 medical students using packed red blood cells of different ABO blood groups. Criteria of evaluation were: agglutination, labelling, handling, and safety regarding possible user injuries. Criteria were rated subjectively according to German school notes ranging from 1 = very good to 6 = very bad/insufficient. RESULTS: Overall, all cards received very good/good marks. The ABO blood group was identified correctly in all cases. Three cards (no. 1, no. 3, no. 4) received statistically significant (p < 0.008) prominence (mean values shown) concerning clearness of agglutination (1.7-1.9 vs. 2.4 for no. 2). Systems with dried antibodies (no. 2, no. 4) outmatched the other systems with respect to overall test system performance (2.0 vs. 2.8-2.9), labelling (1.5 vs. 2.2-2.4), handling (1.9-2.0 vs. 2.5), and user safety (2.5 vs. 3.4). Analysis of card self-explanation revealed no remarkable differences. CONCLUSION: Despite good performance of all card systems tested, the best results when including all criteria evaluated were obtained with card no. 4 (particularly concerning clear agglutination), followed by cards no. 2, no. 1, and no. 3.

[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.

Évolution des risques transfusionnels en 15 ans (1987–2002)

The majority of countries considered the consequences of post-transfusion infections to refer to HIV. However, the organisations and transfusion systems have been revised. The author's objective is now to measure the efficiency of these decisions with regards to risk prevention. The first step was to first draw up a list of these risks so as to obtain a definition which would be accepted throughout Europe. Having looked at the major tendencies between 1993 and 2002, the author made predictions for the following ten years. The ratios benefit-risk and cost-efficiency were also looked at.

Analysis of ABO discrepancies occurring in 35 French hospitals

BACKGROUND

The risk of immunohemolytic reaction owing to ABO-mismatched mistransfusion is 100 to 1000 times higher than the risk of viral infection. Like analysis of incident reports, evaluation of near-miss events can provide useful insight into hazardous situations for mis-matched blood transfusion. The aim of this prospective study was to assess the incidence and root causes of all ABO discrepancies, detected by a central hematology laboratory, in blood samples referred from 35 district hospitals.

STUDY DESIGN AND METHODS

ABO discrepancies were detected by comparing either two current blood specimens or a current and historical specimen collected over a 5-year study period. Discrepancies were investigated by retyping new samples, checking sample identification, and reviewing previous hospital records.

RESULTS

A total of 118 ABO discrepancies were discovered in a series of 407,769 tests carried out during the study period. The incidence of ABO discrepancies was 1 per 3,400. This figure was 10 times higher than the incidence of ABO-mismatched transfusions. Most of these ABO discrepancies were due to phlebotomy errors, that is, collection from wrong patient. The second most common cause involved clerical errors during patient registration or identification.

CONCLUSION

ABO discrepancies can result from errors made not only by the medical staff during phlebotomy but also to by the clerical staff during registration and identification. These findings emphasize the need to standardize data transmission between health care personnel.

[Diversity of bedside pretransfusion ABO compatibility devices in metropolitan France]

To prevent the occurrence of the ABO incidental incompatibility, the bedside pretransfusion ABO control is mandatory in France since 37 years. If the quality of the reagents is regularly controlled, no technical specification exists concerning the type of support. To describe the different types of devices used by the French hospitals, a brief questionnaire was sent, from December 2000 to March 2001, to each hemovigilance correspondent working in the 1782 hospitals with transfusion activity in 1999. Every participant had to send back the device used in his establishment. The rate of replies was 29.4%, varying from a region to another. The devices distributed by laboratories were the most used (67.4%) vs. 25.6% for the devices provided by the regional establishments of the French Establishment of Blood and 6.7% for the devices manufactured by hospitals. The presence in the region of a local office of the French Establishment of Blood providing some devices was the only factor determining the choice of the device type (p < 10(-8)). Almost half of the hospitals (46.8%) declared to have renewed their devices after 1996, most often in favor of a device provided by a laboratory (p < 10(-8)). We evaluated 30 different devices taking into account the general presentation, the available information on the device. The results of this survey showed a large disparity and heterogeneity in the quality of the devices used by the French hospitals in the context of a lack of standardization.

Reliability of bedside ABO testing before transfusion

BACKGROUND

Previous studies of bedside transfusion compatibility tests have shown high rates of erroneous transfusion decision, due to defective techniques and poor user performance. An experimental study was conducted to evaluate the error rate obtained with a new ready-to-use device (Vu-Test, Medigis), in comparison with the most popular bedside card used in France (Safety-Test ABO, Diagast Laboratories).

STUDY DESIGN AND METHODS

A stratified random sample of nurses performed, in the clinical departments where they worked, cross-matches on 12 randomly and blindly selected paired donor-recipient blood samples with Safety-Test ABO and Vu-Test. The nurses detected agglutination, interpreted compatibility, decided whether to transfuse, and gave their opinion of the two devices. Three independent experts reviewed photographs of each test result.

RESULTS

Thirty-five trained nurses and 10 student nurses carried out 268 tests with each device. One-hundred ninety tests (70.9%) performed with Safety-Test ABO and 177 tests (66.0%) performed with Vu-Test were entirely error-free (p=0.23). The risk of erroneous detection of agglutination was not different between the devices (p=0.69), but was significantly lower when the nurse had experience in transfusion (p < 0.001). According to the experts, Vu-Test was significantly better than Safety-Test ABO.

CONCLUSION

Although the experts considered Vu-Test to be better than Safety-Test ABO, error rates were high with both devices.

[Transfusional record and blood grouping methods: essential factors of transfusion safety]

The clinical and biological control of the whole transfusion process is a major preoccupation for everyone dealing with blood transfusion. Specially when the patient is a female recipient or belongs to a group with a high prevalence of alloimmunisation. This case report points out the outstanding importance of the immune compatibility, which must be strongly maintained to prevent any harmful consequences. The transfusional record transmission and a simple and sensitive blood grouping test are essential to increase transfusion safety.

[The field of erythrocyte immunohematology]

Biological tests and clinical practices are both required for the safety of donors and patients in immunohematology. Therefore, the objectives are to require: 1) biological analysis of anti-erythrocyte antibodies and antigens; 2) compatibility tests; 3) analysis for the biological qualification of blood donations; 4) genotyping; 5) qualitative and quantitative studies on antigens and antibodies; 6) clinical stages prior and after biological tests including systems of information, automation and computerization.

[Evolving methods in immunohematology]

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.