Pretransfusion Testing In Patients Research Articles

A Brief Report on Pre-Transfusion Testing in Patients Receiving the Anti-CD38 Monoclonal Antibody for Hematological Disorders in India.

The online version contains supplementary material available at 10.1007/s12288-024-01763-5.

The use of DTT in the resolution of the interferences generated by daratumumab in the blood bank

Abstract Daratumumab (DARA) is a medication that in 2016 proved its efficacy and safety in the treatment of multiple myeloma. This product, based on a monoclonal antibody, technically generates an interference in most blood compatibility tests, artificially producing high blood pan-reactivity and incompatibility. The difficulty in finding blood compatible with the patient's serum can also mask the presence of other clinically significant alloantibodies and, above all, delays the timely delivery of erythrocyte concentrate, which, obviously, endangers the patient's life. In transfusion medicine, very different strategies have recently been described for the resolution of this technical interference. We adopted the use of dithiothreitol (or DTT) to treat the red blood cells of the possible blood donors for the patient, thus achieving the elimination of this technical discrepancy and the adequate, safe and timely selection of this blood component. In the present paper, we describe the first case of a patient with a diagnosis of multiple myeloma treated with DARA, in which the interference caused by this drug in pretransfusion tests was successfully resolved. Communication is a key element in the management of these patients. The doctor should inform the patient and the blood bank about the risk of presenting incompatible cross-tests when they are being treated with this medication. It is additionally recommended that all patients with multiple myeloma should undergo an erythrocyte phenotyping before receiving their treatment with DARA, and carry a card indicating that they are receiving this medication. Fortunately, hemolytic transfusion reactions have not yet been reported in these types of patients at the time of this publication. For the staff at blood banks, it is evident that an additional operating procedure must be in place to describe the technical and administrative operation that must be followed from the admission of these patients to the hospital. Technically speaking, we recommend, based on our experience reported in this case, the use of the DTT technique to resolve this discrepancy and technical difficulty in pretransfusion testing in patients treated with DARA.

Duffy and kidd genotyping facilitates pretransfusion testing in patients undergoing long-term transfusion therapy.

Objective: Conventional serologic typing of red blood cell systems other than ABO and RhD can be inaccurate and difficult to interpret in patients who have recently undergone blood transfusion. While molecular-based assays are not used routinely, the usefulness of genotyping was investigated in order to determine patients who may benefit from this procedure. Materials and Methods: Blood samples were taken from 101 patients with haemato-oncological, chronic renal, or gastroenterological diseases and from 50 donor controls; the samples were tested for Fya and Fyb by applying serologic and genetic methods. All patients had received 3 or more units of RBCs during the last 3 months. An average of 6.1 RBC units were transfused per patient. The average length of time from transfusion until blood sampling was 24.4 days. The haemagglutination test was applied for serological analysis, and the restriction length polymorphism assay was used for genotyping.Results: In total, 33 (32.7%) patients showed positive reactions with anti-Fya or anti-Fyb while being negative genetically. False-positive Fya results were found in 23 samples, and false-positive Fyb in 10 specimens. During the last 3 months, significantly more RBC units were transfused to patients with discrepant results than to those with accurate phenotyping/genotyping results: median of 5 (mean ± SE: 6.85±0.69) versus median of 4 (mean: 5.71±0.51), respectively (p=0.025). The median length of time after the last transfusion was 25 days (mean: 28.72±2.23 days) in the group with accurate phenotyping/genotyping results versus a median of 14 days (mean: 15.52±1.95 days) in the group with discrepant results (p=0.001). Phenotypes and genotypes coincided in all donor samples.Conclusion: Genotyping assays for the Duffy system should be considered if the patient underwent blood transfusion less than 3 or 4 weeks before the sample collection. If the time frame from RBC transfusion exceeds 6 weeks, Duffy phenotyping can provide accurate results.

Transfusion Of Thawed Rare Red Blood Cell Units In Finland

The Finnish Red Cross Blood Service performs blood grouping of all blood donations in Finland and serves as a national reference laboratory in pre-transfusion testing of patients. In addition to ABO and RhD blood groups, other Rh antigens and K antigen are also determined from all red cell units. The antigens of JK, FY, and MNS blood group systems are analyzed from selected donors. The extensive donor typing procedure includes antigens from KEL, LW, LU, CO, DO, DI, YT, GE and CROM blood group systems, performed either serologically or by genotyping. Patients negative for a high frequency blood group antigen present a challenge for transfusion laboratories. A blood group is considered rare if the prevalence is 1:1000 or less, with the most common rare phenotypes in Finland being LWa neg, Jk:-3 and Pk. To ensure the availability of matching blood for patients with a rare blood group, we started a freezing program of rare blood in Finland with Haemonetics ACP 215 process in April 2010. The system is closed, therefore after thawing the units are safe for use for 7 days. 18 blood groups which were included in the program were determined based on the known rare blood groups in the Finnish population. Blood groups which are globally rare but more common in Finland, such as Jk:-3 and LWa neg, are represented in our storage and also available internationally. The aim of the present study was to analyze the status of the freezing program of rare red blood cells in Finland. For the analysis we asked the transfusion data of rare red blood cell units delivered to 10 national and 2 international hospitals. Results: In 2010-2012, altogether 204 units of rare blood were stored, including units of all the predefined rare phenotypes except Vel neg. With the exception of Vel neg, Hrs neg and Oh blood groups, we have been able to meet the need for rare blood in Finland using Finnish donors. Altogether 55 units have been thawed and distributed to 27 adult patients. The indication was delivery in 3 cases, surgery in 6 cases, and chronic anemia in 4 cases. For the present analyses the transfusion data of 49 units was available. The data of 6 Coa neg units is missing. Altogether 22 / 49 (45%) of the units were transfused. In 14 cases the blood was transfused to the patient it was intended for, and in 8 cases to another patient, 27 units were discarded. There were no transfusion associated complications. The hemoglobin response was evaluable in 7 patients. In 4 patients with a chronic anemia the median blood hemoglobin response per a unit was +8 g/l, range +2 - +16 g/l. In 3 patients with blood loss during an operation the median increase in blood hemoglobin value was +7 g/l per unit, range +4 – +12 g/l. Conclusions: Compared to the common 24 hour eligibility of thawed red cell units, our units valid for 7 days are preferable in countries like Finland with long distances and in international rare blood deliveries. We have been able to offer rare blood to Finnish patients. The hemoglobin response was reasonable and there were no transfusion associated complications. Our next challenge will be to recruit Finnish blood donors with different ethnic backgrounds (eg. immigrants) and identify their rare blood groups. We have already expanded our program to include rare combinations of common blood groups. Disclosures: No relevant conflicts of interest to declare.

Evaluation of methods for detecting alloantibodies underlying warm autoantibodies.

In pretransfusion testing of patients whose sera contain autoantibodies reacting optimally at 37 degrees C, it must be determined whether alloantibodies are also present. Two approaches, testing a 1-in-5 dilution of patients' sera and the adsorption of sera in the presence of polyethylene glycol (PEG), have been proposed as alternatives to the time-consuming approach of adsorbing sera with ficin- or ZZAP-treated red cells (RBCs). The three approaches were compared. Patients' sera containing warm autoantibodies, with and without alloantibodies, were retested 1) after dilution (1-in-5) and 2) after adsorption with allogeneic RBCs in the presence of PEG. Results were compared to those after adsorption with ZZAP-treated allogeneic RBCs. Dilution (1-in-5): Twenty-seven of 119 sera (7/26 [27%] with and 20/93 [22%] without alloantibodies) did not react; one example each of alloanti-D, -E, -e, -Fy(a), and -Jk(a), and two examples of anti-Jk(b) were not detected at a dilution of 1 in 5. Alloantibodies were identified in 5 (19%) of 26 1-in-5 diluted sera containing alloantibodies; 87 (73%) of 119 sera still reacted with all cells and would have required further workup. PEG adsorption: Thirty-nine sera were tested after parallel PEG and ZZAP adsorptions. The PEG adsorptions required a total of 55 aliquots of adsorbing cells and 13.75 hours, whereas ZZAP adsorptions required 61 aliquots and 30.5 hours. All alloantibodies (anti-D [3], -C [2], -c [1], -E [4], -K [2], -Fy(a) [1], -Jk(a) [2], -Jk(b) [1]) reacted in the adsorbed serum-PEG mixtures at a strength equal to or greater than that in the ZZAP-adsorbed sera. Although the 1-in-5 dilution approach is convenient, only 22 percent of warm autoantibodies without alloantibodies were nonreactive, and 27 percent of alloantibodies of potential clinical significance were not detected. PEG adsorption appears to give similar results to those of ZZAP adsorption, but it has the advantages of eliminating the cost and time of prior treatment of the allogeneic adsorbing cells and of a reduction of at least a 50 percent in adsorption time.

The efficacy of performing red cell elution studies in the pretransfusion testing of patients with positive direct antiglobulin tests.

In order to evaluate the efficacy of performing red cell elutions in pretransfusion testing, the serologic records of 638 patients with positive direct antiglobulin tests (DAT) were reviewed. These patients were identified by routine antibody screening procedures that included an autologous control. DAT results on the red cells of these patients showed 279 with IgG and C3d sensitization, 319 with IgG alone, and 40 with C3d sensitization alone. Of 638 patients' red cell eluates, 401 demonstrated no reactivity, 154 demonstrated panagglutination, and 60 demonstrated passively acquired anti-A,B. Only 23 of 638 patients had alloantibody sensitization of their red cells. Of the 23, 19 had serum antibody corresponding to the specificity of antibody detected in the eluate. Thus, only four of 638 (0.6%) eluates gave results unavailable by serum testing alone. This study indicates that routine eluate investigation provides little useful information in assuring compatibility. Serum antibody testing and careful review of the clinical and transfusion history constitute appropriate pretransfusion testing in patients with positive direct antiglobulin tests. Eluate testing should be restricted to cases in which immune hemolysis is suspected clinically.

Factors associated with positive direct antiglobulin tests in pretransfusion patients: a case-control study.

During routine pretransfusion testing, the presence of IgG on patient red cells is suggested by a positive autocontrol and confirmed by a positive direct antiglobulin test (DAT) using monospecific anti-IgG sera. Most IgG on patient red cells detected in this manner are of unknown etiology. We recently showed an association between elevated serum globulin levels and positive DAT with unreactive eluate in patients with acquired immunodeficiency syndrome (AIDS). In the present study, we wished to determine whether elevated serum globulin levels contribute to some of the positive DAT encountered in pretransfusion testing of patients without AIDS. 76 patients with positive DAT were compared with 90 controls without IgG detected on their red cells during pretransfusion testing. The rate of elevated serum globulin levels was 75% in positive DAT cases versus 29% in controls (p less than 0.001); the odds ratio was 7.6. Elevated blood urea nitrogen levels occurred in 42% of cases versus 19% of controls (p less than 0.025); the odds ratio was 3.1. Cases and controls were not significantly different with regard to age, sex, race, quinidine usage, or hyperalimentation. Elevated serum globulin and blood urea nitrogen levels are significantly associated with a positive DAT with unreactive eluate in pretransfusion patients.