Allo-anti-M: Detection peaks around 2 years of age, but may be attenuated by red blood cell transfusion.

BACKGROUND: Anti-M is frequently observed as a naturally occurring antibody of little clinical significance. Naturally occurring anti-M is often found in children although the specific triggers of production, persistence, and evanescence of anti-M have yet to be elucidated. METHODS: In a retrospective, multicenter, nationwide cohort survey conducted from 2001 to 2015, alloantibody screening was performed before and after transfusion in 18,944 recipients younger than 20 years. Recipients were categorized into six cohorts based on their age at transfusion; within and among these cohorts, allo-anti-M was analyzed in regard to its production, persistence, and evanescence. RESULTS: In 44 patients, anti-M detected before and/or after transfusion was an age-related phenomenon, with a median age of 2 years and an interquartile range of 1-3 years; anti-M was most frequently detected in a cohort of children 1 to <5 years (0.77%, 31 of 4035). At least five patients were presumed to have concurrent infections. Among 1575 adolescents/young adults (15 to <20 years), no anti-M was detected. Of 29 patients with anti-M prior to transfusion, the antibody fell to undetectable levels in 17 recipients (89.5%, of whom at least 13 received only M-negative red cells) after anywhere from 5 days to 5.8 years; anti-M persisted in 2, and was not tested in 10. Only 15 recipients (0.08%) produced new anti-M after transfusion. CONCLUSION: Naturally occurring anti-M is a phenomenon of younger ages, predominantly between 1 and 3 years. After transfusion, it often falls to undetectable levels.

Transfusion-associated circulatory overload and high blood pressure: A multicentre retrospective study in Japan.

BACKGROUND: Transfusion-associated circulatory overload (TACO) is an adverse reaction associated with a high risk of mortality. The actual incidence of TACO and hypertension associated with transfusion in Japan is unknown. METHODS: A multicentre retrospective observational study was conducted across 23 institutions during the 1-year period of 2016. Patients were included if they developed TACO or their blood pressure (either systolic or diastolic) increased by at least 30 mmHg during the transfusion. TACO was confirmed by the primary physicians and transfusion medicine teams and recorded in the data on passive surveillance, and additional data were extracted from electronic medical records. RESULTS: In our patient cohort of 31 384 patients who underwent transfusion, the incidence of TACO and hypertension was 0·03% and 0·2%, respectively. However, 43% of the participating institutions didn't report any cases. When comparing risk factors between the TACO and hypertension groups, there were significant differences in comorbidities, such as abnormal findings on chest x-ray. Significant differences between the two groups were observed post-transfusion pulse rate, body temperature and oxygen saturation (P < 0·01). In the group of patients with hypertension, the level of BNP increased significantly after transfusion in 45% (5/11) of the patients. We identified 4 patients in the hypertension group who met the new ISBT's TACO criteria. CONCLUSION: Our study suggests that more attention should be given to TACO in Japan, particularly in terms of improving surveillance systems. For the early diagnosis of TACO, it is crucial to carefully monitor vital signs including blood pressure.

A newly devised flow cytometric antibody binding assay helps evaluation of dithiothreitol treatment for the inactivation of CD38 on red blood cells.

BACKGROUND AND OBJECTIVES: Anti-CD38 monoclonal antibodies, including daratumumab and isatuximab, often interfere with pretransfusion testing. Dithiothreitol (DTT) treatment of red blood cells (RBCs) negates this interference. However, the optimum DTT concentration and treatment time have not been well defined. Here, we quantified CD38 on RBCs before and after DTT treatment using a flow cytometric antibody binding assay (FABA) to specify the optimum conditions for CD38 inactivation. MATERIALS AND METHODS: For FABA, untreated or DTT-treated RBCs were incubated with fluorescein isothiocyanate-labelled anti-CD38 antibody, in the presence or absence of 100-fold or more excess of unlabelled anti-CD38 antibody, and then analysed by flow cytometry (FCM). Dissociation of CD38-positive and control histograms was determined from the D-value using the Kolmogorov-Smirnov test. The results from FABA were compared with those from conventional FCM, indirect antiglobulin test (IAT) and Western blotting. RESULTS: The results from FABA were more consistent than those from conventional FCM. The D-value was found to be reliable in the analysis of difference between CD38 before and after DTT treatment. Our data showed that 0·0075 mol/l DTT for 30 min is sufficient to inactivate CD38 on RBCs. These results were stable and consistent with the findings from IAT. CONCLUSION: Flow cytometric antibody binding assay is an objective way of evaluating the efficacy of DTT treatment for CD38 on RBCs. This approach allows the detection of a small number of cell surface antigens and will be useful for assessing the various chemical treatments to denature RBC antigens.

Erythrocyte Alloimmunity and Genetic Variance: Results from the Collaborative Study of Alloimmunity to Antigen Diversity in Asian Populations (All ADP).

As an East-Asian international study, we evaluated erythrocyte alloimmunity by gender and history of transfusion or pregnancy. In total, data from more than 1,826,000 patients were analyzed, from whom 26,170 irregular erythrocyte antibodies were detected in 22,653 cases. Antibody frequencies in these cases were as follows: anti-E, 26.8%; anti-Lea, 20.0%; anti-P1, 7.1%; anti-M, 6.4%; anti-Mia, 5.6%; anti-c + E, 5.6%; anti-Leb, 4.6%; anti-D, 2.8%; anti-Fyb, 2.6%; anti-Lea+Leb, 2.5%; anti-Dia, 2.0%; and others. For pregnant patients, anti-D (12.7%) was statistically more frequent. For transfused patients, anti-E (37.3%), anti-c + E (9.5%), anti-C + e (3.3%) and anti-Jka (3.1%) were significantly more frequent.

Predictors of early death, serious hemorrhage, and differentiation syndrome in Japanese patients with acute promyelocytic leukemia.

Significant advancements have been achieved with regard to the outcomes of acute promyelocytic leukemia (APL) patients through the introduction of all-trans retinoic acid; however, early hemorrhagic death and differentiation syndrome remain the major causes of remission induction failure in patients with APL. To investigate early death, serious hemorrhage, and differentiation syndrome during remission induction therapy in terms of incidence, risk factors, influence on outcomes, and prophylactic effects of several new anticoagulants, the results of 344 patients enrolled in the Acute Promyelocytic Leukemia 204 study conducted by the Japan Adult Leukemia Study Group were analyzed. Early death was observed in 16 patients (4.7%), of whom 14 had serious hemorrhage and 2 had differentiation syndrome. Serious hemorrhage and differentiation syndrome of grade 2 or higher were observed in 21 and 54 patients, respectively. Patients who achieved complete remission had a 7-year disease-free survival of 84.8% if they did not experience serious hemorrhage and 40.0% if they experienced serious hemorrhage during remission induction therapy (P = 0.001). Risk factor analyses showed that higher white blood cell count was associated with early death, higher white blood cell count and lower platelet count with serious hemorrhage, and leukocytosis during induction therapy and higher body surface area with differentiation syndrome. In conclusion, these results indicate that patients with such high-risk features may benefit from more intensive supportive care. The hemorrhagic risk was not relieved by the introduction of new anticoagulants. Further studies are required to establish the predictive impact of body surface area on differentiation syndrome. This trial is registered with UMIN-CTR as C000000154 on September 13, 2005.

Differences among hemoglobin thresholds for red blood cell transfusions in patients with hematological diseases in teaching hospitals: a real world data in Japan.

A hemoglobin (Hb) threshold level of 7 g/dL has been proposed for red blood cell (RBC) transfusion in patients with chronic anemia in the Japanese guideline since 2005. However, Hb thresholds for hematological diseases in clinical practice and factors responsible for higher Hb thresholds remain unclear. Hb thresholds were collected for patients with hematological diseases from 32 Japanese teaching hospitals. Uni- and multivariate analyses were used to analyze relationships between Hb threshold level and various patient and hospital factors. In total, 4996 units of RBC were transfused to 1054 patients with hematological diseases in 2421 transfusions. Median age was 68 years. Myelodysplastic syndrome was the most frequent diagnosis. Overall median Hb threshold level was 6.9 g/dL. Multivariate linear regression analysis detected the following variables associated with Hb threshold level: hospital; cardiovascular disease; symptomatic anemia; and hematopoietic stem cell transplantation. Hospital was the most significant factor. Collectively, median Hb threshold level in clinical practice in Japan was similar to the guidelines. Higher Hb threshold level depended on the hospitals at which the transfusions were performed as well as patient condition. Educational approaches directed toward hospitals may be useful to promote transfusion guidelines.

Impact of CD56 Continuously Recognizable as Prognostic Value of Acute Promyelocytic Leukemia: Results of Multivariate Analyses in the Japan Adult Leukemia Study Group (JALSG)-APL204 Study and a Review of the Literature.

BACKGROUND: After long-term analysis of the JALSG-APL204 study we recently reported that maintenance therapy with tamibarotene was more effective than all-trans retinoic acid (ATRA) by reducing relapse in APL patients. Here, the clinical significance of other important prognostic factors was evaluated with multivariate analyses. PATIENTS AND METHODS: Newly diagnosed acute promyelocytic leukemia (APL) patients were registered with the study. Induction was composed of ATRA and chemotherapy. Patients who achieved molecular remission after consolidation were randomly assigned to maintenance with tamibarotene or ATRA. RESULTS: Of the 344 eligible patients, 319 (93%) achieved complete remission (CR). After completing consolidation, 269 patients underwent maintenance random assignment-135 to ATRA, and 134 to tamibarotene. By multivariate analysis, overexpression of CD56 in blast was an independent unfavorable prognostic factor for relapse-free survival (RFS) (p = 0.006) together with more than 10.0 × 109/L WBC counts (p = 0.001) and the ATRA arm in maintenance (p = 0.028). Of all phenotypes, CD56 was related most clearly to an unfavorable prognosis. The CR rate, mortality rate during induction and overall survival of CD56+ APL were not significantly different compared with CD56- APL. CD56 is continuously an independent unfavorable prognostic factor for RFS in APL patients treated with ATRA and chemotherapy followed by ATRA or tamibarotene maintenance therapy.

Clinical significance of autologous blood transfusions in bone marrow harvest from unrelated donors.

In the Japan Marrow Donor Program (JMDP), autologous blood is collected from most unrelated bone marrow (BM) donors. We retrospectively evaluated 5772 donors who underwent BM harvest between 2010 and 2015 through the JMDP. Autologous blood was collected in 96.8% of the donors; the wastage rate was 0.6%. Allogeneic blood transfusion was not required. The mean hemoglobin (Hb) levels were 12.1 g/dL after the BM harvest (mean 891 mL) together with autologous blood transfusion (mean 596 mL). Propensity-score matching was used to adjust the backgrounds. Among donors with harvested BM of 100-400 mL, autologous blood transfusion had no impact on Hb levels or complications after BM harvest. Among donors with harvested BM of > 400 mL, more autologous blood transfusion followed by a bleeding volume of ≤ 100 mL did not confer clinical benefit to donors compared with less autologous blood transfusion followed by a bleeding volume of > 300 mL. The findings of the present study suggest that autologous blood transfusion to BM donors is excessive in terms of Hb changes and post-harvest outcomes.

A Japanese multi-institutional collaborative study of antigen-positive red blood cell (RBC) transfusions in patients with corresponding RBC antibodies.

BACKGROUND AND OBJECTIVES: It is sometimes difficult to obtain antigen-negative red blood cells (RBCs) for patients with antibodies against RBCs. However, the frequency and severity of the adverse reactions have not been well elucidated. Here, we conducted a multi-institutional collaborative study to clarify the background, frequency and clinical significance of antigen-positive RBC transfusions to patients with the respective antibodies. MATERIALS AND METHODS: The survey included the background of patients, antigens on RBCs transfused, total amount of antigen-positive RBCs transfused, results from antibody screen and direct antiglobulin tests, specificity of antibodies, adverse reactions and efficacies. All antibodies were surveyed regardless of their clinical significance. RESULTS: In all, 826 cases containing 878 antibodies were registered from 45 institutions. The main reasons for antigen-positive RBC transfusions included 'negative by indirect antiglobulin test' (39%) and 'detection of warm autoantibodies' (25%). In 23 cases (3% of total), some adverse reactions were observed after antigen-positive RBC transfusion, and 25 antibodies (9 of 119 clinically significant and 16 of 646 insignificant antibodies) were detected. Non-specific warm autoantibodies were detected in 9 cases, anti-E in 5 cases, 2 cases each of anti-Lea , anti-Jra or cold alloantibodies, and 1 case each of anti-Dib , anti-Leb or anti-P1. Other antibodies were detected in 2 further cases. Five (22%) of these 23 cases, who had anti-E (3 cases) or anti-Jra (2 cases), experienced clinically apparent haemolysis. CONCLUSIONS: Adverse reactions, especially haemolysis, were more frequently observed in cases with clinically significant antibodies than those with clinically insignificant antibodies (P < 0·001).

Phase II study of FLAGM (fludarabine + high-dose cytarabine + granulocyte colony-stimulating factor + mitoxantrone) for relapsed or refractory acute myeloid leukemia.

Given the poor prognosis of patients with relapsed/refractory acute myeloid leukemia (AML), better therapy is needed. Fludarabine enhances the efficacy of Ara-C (cytarabine) by increasing intracellular Ara-C-triphosphate. The FLAG (fludarabine, high-dose Ara-C, supported with granulocyte colony-stimulating factor) regimen has been tested for use in AML patients by other investigators. In the phase II study reported here, we evaluated the efficacy and toxicity of FLAGM therapy (FLAG with mitoxantrone), further intensified by adding mitoxantrone, based on the results of a phase I study by our group. The major endpoints were complete remission (CR) rate and early death. From June 2004 to February 2008, 41 patients (median age 52 years; range 18-64 years) were enrolled. Thirty (73% 95% CI 58-84%) patients achieved CR, which met the primary endpoint; there was a single case of early death from pneumonia. Two-year overall survival was 39.4% (95% CI 25.2-55.6%). Of those who achieved CR, 27 underwent allogeneic stem cell transplantation (SCT), and 12 SCT recipients showed long-term survival. Grade 3/4 non-hematological adverse events included infection (59%), nausea/vomiting (15%), diarrhea (7%), and elevated liver enzymes (7%). In conclusion, FLAGM is an effective and safe salvage therapy for patients with relapsed/refractory AML, and facilitated SCT for a large proportion of patients.

Tamibarotene maintenance improved relapse-free survival of acute promyelocytic leukemia: a final result of prospective, randomized, JALSG-APL204 study.

Between April 2004 and December 2010, we conducted a prospective randomized controlled study comparing tamibarotene with all-trans retinoic acid (ATRA) in the maintenance therapy of newly diagnosed acute promyelocytic leukemia (APL), and here report the final results of this study with a median follow-up of 7.3 years. Of 344 eligible patients who had received ATRA and chemotherapy, 319 (93%) achieved complete remission (CR). After completion of three courses of consolidation chemotherapy, 269 patients in molecular remission underwent maintenance randomization, 135 to ATRA (45 mg/m2 daily), and 134 to tamibarotene (6 mg/m2 daily) for 14 days every 3 months for 2 years. The primary endpoint was relapse-free survival (RFS). The 7-year RFS was 84% in the ATRA arm and 93% in the tamibarotene arm (p = 0.027, HR = 0.44, 95% CI, 0.21 to 0.93). The difference was prominent in high-risk patients with initial leukocytes ≥ 10.0 × 109/L (62% vs. 89%; p = 0.034). Tamibarotene was significantly superior to ATRA by decreasing relapse in high-risk patients. Overall survival after randomization did not differ (96% vs. 97%; p = 0.520). Secondary hematopoietic disorders developed in nine patients, secondary malignancies in 11, and grade 3 or more late cardiac comorbidities in three. These late complications did not differ between the two arms.

Clinical significance of ASXL2 and ZBTB7A mutations and C-terminally truncated RUNX1-RUNX1T1 expression in AML patients with t(8;21) enrolled in the JALSG AML201 study.

We analyzed the clinical significance and genetic features of ASXL2 and ZBTB7A mutations, and the alternatively spliced isoform of the RUNX1-RUNX1T1 transcript, which is also called AML1-ETO9a (AE9a), in Japanese CBF-AML patients enrolled in the JALSG AML201 study. ASXL2 and ZBTB7A genes were sequenced using bone marrow samples of 41 AML patients with t(8;21) and 14 with inv(16). The relative expression levels of AE9a were quantified using the real-time PCR assay in 23 AML patients with t(8;21). We identified ASXL2 (34.1%) and ZBTB7A (9.8%) mutations in only AML patients with t(8;21). ASXL2-mutated patients had a significantly higher WBC count at diagnosis (P = 0.04) and a lower frequency of sex chromosome loss than wild-type patients (33 vs. 76%, respectively, P = 0.01). KIT mutations were the most frequently accompanied with both ASXL2 (36%) and ZBTB7A (75%) mutations. Neither ASXL2 nor ZBTB7A mutations had an impact on overall or event-free survival. Patients harboring cohesin complex gene mutations expressed significantly higher levels of AE9a than unmutated patients (P = 0.03). In conclusion, ASXL2 and ZBTB7A mutations were frequently identified in Japanese AML patients with t(8;21), but not in those with inv(16). Further analysis is required to clarify the detailed biological mechanism of AE9a regulation of the cohesin complex.

Released washed platelet concentrates are effective and safe in patients with a history of transfusion reactions.

BACKGROUND: Plasma removal by washing is an effective approach to prevent transfusion reactions by platelet concentrates (PCs). Recently, washed PCs were released by the Japanese Red Cross Society (JRCS). MATERIALS AND METHODS: This retrospective multicenter study evaluated the efficacy and safety of released washed PCs (RWPCs) between September 2016 and January 2017 in Japan. The RWPCs were prepared by washing leukoreduced apheresis PCs with the platelet additive solution, BRS-A, using automated cell processors. RESULTS: Clinical data were obtained from 91 patients and 1210 RWPC transfusions at 50 institutions. The median number of RWPC transfusions per patient was 8 (range, 1-91). RWPCs were used in 94.5% of the patients with a history of recurrent or severe transfusion reactions for preventing such reactions. Responses of RWPCs were evaluated as complete response (91.6%), partial response (8.2%), no-change (0.2%), and progression (0%) and overall response was equal across subgroups divided by patients' profiles. The median corrected count increment (CCI) at 1 and 24 h post-transfusion were 13.5 (range, 1.9-35.4) × 109/L and 3.5 (range, -13 to 53.6) × 109/L, respectively, and median CCI at 24 h was 5.5 (range, -13 to 53.6) × 109/L in patients without risk factors associated with platelet transfusion refractoriness. Transfusion reactions to RWPCs were observed in only nine transfusions (0.7%), all of which were mild allergic reactions. CONCLUSION: This study demonstrated that RWPCs were effective and safe in patients with a history of transfusion reactions. Further prospective studies on efficacy together with cost-benefit analysis in RWPCs are needed.

Prognostic analysis according to the 2017 ELN risk stratification by genetics in adult acute myeloid leukemia patients treated in the Japan Adult Leukemia Study Group (JALSG) AML201 study.

Many genetic alterations that are associated with the prognosis of acute myeloid leukemia (AML) have been identified, and several risk stratification systems based on the genetic status have been recommended. The European LeukemiaNet (ELN) first proposed the risk stratification system for AML in 2010 (ELN-2010), and recently published the revised system (ELN-2017). We validated the long-term prognosis and clinical characteristics of each ELN-2017 risk category in Japanese adult AML patients who were treated in the Japan Adult Leukemia Study Group (JALSG) AML-201 study. We demonstrated that the 3-risk category system of the ELN-2017 successfully discriminated the overall survival and complete remission rates in our cohort in comparison with the 4-risk category of the ELN-2010. However, there were still genetic categories in which stratification of patients into favorable or intermediate risk categories was controversial; the low allelic ratio of FLT3-ITD was not necessarily associated with a better prognosis in patients with FLT3-ITD, and cytogenetic abnormalities may affect the prognosis in patients with favorable genetic lesions such as NPM1 and CEBPA mutations. As many molecular targeting agents, such as FLT3 inhibitors, have been developed, we must continue to modify the genetic risk stratification system to match the progression of therapeutic strategies.

A national survey of premedication for transfusion reactions in Japan.

BACKGROUND: Premedication before transfusion is commonly administered in clinical practice despite a lack of evidence for its efficacy. The aim of this study was to clarify the status of premedication and evaluate expert opinions regarding its use in Japanese medical institutions. METHOD: Between May and July 2016, we conducted a questionnaire survey on premedication before transfusion in 252 medical institutes that were certified by an academic society or employed transfusion experts. RESULTS: A total of 141 institutes (54.2%) responded, and hematologists (n=113) comprised the most frequent respondents. The purpose of premedication was to prevent urticaria, pruritus, and fever, and washed blood products were used for anaphylactic shock or refractory transfusion reactions before. Drugs for premedication were intravenously administered either just before or 30min before transfusion. Both inpatients and outpatients were premedicated in a similar manner, and institutional guidelines were not established. More than half of the experts recognized premedication as efficient and necessary, and premedication for previous transfusion reactions was frequently implemented, particularly for platelet transfusion or in patients with hematological diseases. Some institutions administered one or more drugs for premedication from the first transfusion. Antihistamines and hydrocortisone were the most frequently used as premedication. CONCLUSION: Our study reports the current status of premedication for transfusion in Japan. Antihistamines and hydrocortisone were most commonly used for premedication despite a lack of evidence of their use. These findings may help clarify the indications for premedication and the use of washed blood products.

Involvement of transfusion unit staff in the informed consent process.

BACKGROUND AND OBJECTIVES: Obtaining informed consent (IC) for a blood transfusion is an absolute requirement. In this study, we compared the depth of understanding of blood transfusion among patients with or without an explanation by the transfusion unit staff and evaluated the usefulness of this intervention in obtaining IC. MATERIALS AND METHODS: Expert staff from the transfusion unit started to provide patients with a basic explanation of blood transfusion (intervention group, n = 129). The efficacy of this strategy was assessed by comparison with explanation given by the primary doctors only (conventional group, n = 31). We performed a questionnaire survey to analyze the length of time spent providing information of blood transfusion and the depth of understanding of blood transfusion in the two groups. RESULTS: The median time in providing information in the conventional and intervention groups was 6 and 20 minutes, respectively (P < 0.0001). Patients in the intervention group had a better understanding of several key points on blood transfusion than those in the conventional group. CONCLUSION: Our results show that expert staff from the transfusion unit should be involved in obtaining IC for a blood transfusion. Patients who were provided information by transfusion unit staff were more likely to have a better understanding of the risks and benefits of transfusion.

Evaluation of the in-hospital hemovigilance by introduction of the information technology-based system.

BACKGROUND: Hemovigilance is an important aspect of transfusion medicine. However, the frequency of the adverse reactions often varies using different reporters. Recently, we have employed a new information technology (IT)-based in-hospital hemovigilance system. Here, we evaluated changes in practice after implementation of an IT-based reporting system. STUDY DESIGN AND METHODS: We compared the rate of frequency and details of blood transfusion-related adverse reactions 3 years before and after introduction of the IT-based reporting system. Contents and severity of the adverse reactions were reported in a paper-based reporting system, but input by selecting items in an IT-based reporting system. The details of adverse reactions are immediately sent to the blood transfusion unit online. RESULTS: After we introduced the IT-based reporting system, the reported rate of transfusion-related adverse reactions increased approximately 10-fold from 0.20% to 2.18% (p < 0.001), and frequencies of urticaria, pruritus, rash, fever (p < 0.001), hypertension (p = 0.001), tachycardia (p = 0.003), and nausea and vomiting (p = 0.010) increased significantly. Although there was no error report in the paper-based reporting, incorrect reports were observed in 90 cases (0.52%) in the IT-based reporting (p < 0.001). CONCLUSION: The advantages of IT-based reporting were: 1) a significant increase in the frequency of adverse reaction reporting and 2) a significant decrease in underreporting, although the true frequency has yet to be clarified. The disadvantage of the IT-based reporting was an increased incidence of incorrect inputs, all of which was unnoticed by the reporters. Our results showed several important points in need of monitoring after introduction of an IT-based reporting system.