Possible Utility of the Basophil Activation Test for the Analysis of Mechanisms Involved in Allergic Transfusion Reactions

Pilot study on the use of basophil activation tests and skin tests for the prevention of allergic transfusion reactions

Background and objectives

Management of severe allergic transfusion reactions (ATR) is challenging. In this study, we investigate the usefulness of skin tests and basophil activation tests (BAT) in chronically transfused patients for the prevention of future ATR.

Materials and methods

BAT and skin tests were carried with the supernatant of red blood cell (RBC) units for a sickle-cell disease patient under chronic exchange transfusion who has presented a severe ATR, in order to prevent potential future ATR. If the results for both BAT and skin tests were negative, the RBC units could be transfused to the patient. If either one of the results was positive, the tested RBC unit was discarded for the patient.

Results

192 RBC units were tested with both tests. The level of results concordance between the two tests was 95%. Out of the 169 negative units with both tests, 118 units were transfused to the patient for which he presented no ATR.

Conclusion

In our study, combining both BAT and skin tests was associated with a good negative predictive value since we were able to safely transfuse our patient. Further studies are still necessary to confirm this result but this pilot study indicates that skin tests and BAT might help prevent ATR. When BAT is not available, skin tests may also be useful in preventing ATR.

Passive immune basophil activation test for the identification of allergic episodes from various adverse events elicited by haematopoietic cell transplantation: A pilot study

BACKGROUND AND OBJECTIVES

Haematopoietic cell transplantation (HCT) therapy tends to be associated with various complications including engraftment failure, regimen-related toxicities, and infectious diseases. In addition, HC infusion itself occasionally elicits adverse events (AEs), one of the most common AEs is an allergic reaction. As appropriate laboratory tests have not yet been established to distinguish allergy-mediated AEs from other complications, clinical responses for HCT-related AEs can only be nonspecific. In this pilot study, using passive immune basophil activation test (pi-BAT), we attempted to distinguish an HC infusion-induced allergic reaction from various HCT-related AEs.

MATERIALS AND METHODS

Using pi-BAT, we examined 34 patients who underwent HCT, that is, 11 with AEs and 23 without AEs as controls.

RESULTS

Two of the eleven AE cases were pi-BAT positive and, the rest of nine AE cases were negative, while all non-AE cases were negative. Both of the two positive cases showed erythema, tachycardia, plus cough. Because erythema is one of the representative symptom of allergy, those cases could be classified as allergic reaction cases or anaphylaxis cases if tachycardia and cough were concomitant symptoms of erythema. Among the nine AEs with pi-BAT negative result, four cases showed urticaria, four showed vomiting plus diarrhoea, and one showed cough. Urticaria case was strongly suspected of allergy, however, the AE cases were pi-BAT negative.

CONCLUSION

The pi-BAT may be useful as an auxiliary diagnostic tool to confirm the possible involvement of HC infusion in HCT-related AEs and identify an immunologic mechanism for HCT-related hypersensitivity reactions.

Immunoglobulin (Ig)G antibodies against IgE identified by basophil activation test as the putative causative agent of a serious allergic transfusion reaction: potential utility of the test as a new safety measure for allergic transfusion reactions

BACKGROUND

In most cases of allergic transfusion reactions (ATRs), the causative agents have not been identified and the mechanisms are largely unknown, with a few exceptions. The basophil activation test (BAT) was recently introduced in the field of transfusion to investigate the causal relationships between ATRs and transfusion, as well as the mechanisms behind them.

STUDY DESIGN AND METHODS

The BAT was used to screen the residual supernatants (SNs) of 43 blood components associated with serious ATRs for those that can activate basophils of many healthy volunteers. The SNs were then fractionated by centrifugal ultrafiltration and protein G column chromatography and each separated fraction was reexamined by the BAT.

RESULTS

Of the 43 such blood components, one activated basophils from 19 of 21 healthy volunteers. In the blood component, the IgG antibody against IgE was identified as a putative causative agent.

CONCLUSION

Blood donors who possessed the IgG antibody against IgE may be dangerous to transfusion recipients. The BAT would be useful in identifying such high-risk blood donors, when it is used to screen the blood components associated with serious ATRs for residual SNs that can activate the basophils of many healthy volunteers.

Transfusion-associated hazards: A revisit of their presentation

As a therapy or a support to other therapies, despite being largely beneficial to patients in general, transfusion it is not devoid of some risks. In a moderate number of cases, patients may manifest adverse reactions, otherwise referred to as transfusion-associated hazards (TAHs). The latest French 2016 haemovigilance report indicates that 93% of TAHs are minor (grade 1), 5.5% are moderate (grade 2) and 1.6% are severe (grade 3), with only five deaths (grade 4) being attributed to transfusion with relative certainty (imputability of level [or grade] 1 to 3). Health-care providers need to be well aware of the benefits and potential risks (to best evaluate and discuss the benefit-risk ratio), how to prevent TAHs, the overall costs and the availability of alternative therapeutic options. In high-income countries, most blood establishments (BEs) and hospital blood banks (HBBs) have developed tools for reporting and analysing at least severe transfusion reactions. With nearly two decades of haemovigilance, transfusion reaction databases should be quite informative, though there are four main caveats that prevent it from being fully efficient: (ai) reporting is mainly declarative and is thus barely exhaustive even in countries where it is mandatory by law; (aii) it is often difficult to differentiate between the different complications related to transfusion, diseases, comorbidities and other types of therapies in patients suffering from debilitating conditions; (aiii) there is a lack of consistency in the definitions used to describe and report some transfusion reactions, their severity and their likelihood of being related to transfusion; and (aiv) it is difficult to assess the imputability of a particular BC given to a patient who has previously received many BCs over a relatively short period of time. When compiling all available information published so far, it appears that TAHs can be analysed using different approaches: (bi) their pathophysiological nature; (bii) their severity; (biii) the onset scheme; (biv) a quality assessment (preventable or non-preventable); (bv) their impact on ongoing therapy. Moreover, TAHs can be reported either in a non-integrative or in an integrative way; in the latter case, presentation may also differ when issued by a blood establishment or a treating ward. At some point, a recapitulative document would be useful to gain a better understanding of TAHs in order to decrease their occurrence and severity and allow decision makers to determine action plans: this is what this review attempts to make. This review attempts to merge the different aspects, with a focus on the hospital side, i.e., how the most frequent TAHs can be avoided or mitigated.