Apheresis Platelet Transfusions Research Articles

Nomogram for the Therapeutic Efficacy of Apheresis Platelet Transfusion in Hematologic Patients

Nomogram for the Therapeutic Efficacy of Apheresis Platelet Transfusion in Hematologic Patients

Plateletcrit and absolute immature platelet count are not impacted by platelet transfusions: a single-centre prospective study

BACKGROUND This is the first study in which the impact of platelet transfusions on seven platelet indices was evaluated in platelet transfusion-dependent patients admitted in the ICU. STUDY DESIGN AND METHODS Among a cohort of 21 ICU patients prospectively studied over eleven months, a total of 19 ICU patients were enrolled. Seven platelet indices were measured before and then, within 18–24 h, after platelet transfusions using the Sysmex XN-10 analyser and statistically investigated as follows: i) apheresis vs. pooled platelet transfusions; ii) pre– vs. post–platelet transfusions; and iii) platelet count (PC) increment vs. PC decrement group. RESULTS A 79.2% of platelet transfusion episodes in ICU patients showed an increase in PC increment within 18–24 h, of which 73.7% had a peak percentage immature platelet fraction (%-IPF) above 10.0% during their stay. No difference was observed in the measurements of platelet indices between the apheresis and pooled platelet transfusion doses (all p > 0.05). Of the seven platelet indices investigated, plateletcrit (PCT) and absolute immature platelet count (A-IPF) were not influenced by platelet transfusions and thus proven to be stable (0.06 vs. 0.07%, p = 0.0901 and 4.6 vs. 4.9 × 109/L, p = 0.4559, respectively), despite their close proximity to platelet transfusion. But the overall effectiveness of these indices in detecting changes over time was not hindered. CONCLUSION A-IPF and PCT are stable after platelet transfusions, regardless of whether patient’s respond to or do not respond to platelet transfusion doses. PCT and A-IPF may thus prove useful in monitoring patient transfusion support and guiding management in thrombocytopenic patients.

A Case of Spontaneous Intracranial Hematoma with Critically Low Platelet Count: A Neurointensivist's Nightmare

AbstractComplications of immune thrombocytopenia (ITP) are more frequent at a platelet count lower than 10,000/μL of blood. Intracranial hematoma (ICH) is one of the most severe complications of ITP. Subdural hematoma (SDH) and subarachnoid hemorrhage (SAH) usually occur as extensions of ICH and is generally spontaneous in nature. We report a case of ICH along with SDH and SAH who presented with critically low platelet count managed using apheresis platelet transfusion, desmopressin, intravenous immunoglobulin, and methylprednisolone. The patient was discharged successfully from hospital without any neurological deficit. The importance of early referral and immediate aggressive management and monitoring at an advanced center is suggested.

Comparison of Therapeutic Effect of Apheresis Platelets and Buffy Coat-Derived Platelet Concentrates.

The study aimed to investigate the difference in clinical efficacy between apheresis platelets and buffy coat-derived platelet concentrates infusion in patients with hematological diseases. A total of 218 patients with hematological diseases were enrolled in Xi'an Central Hospital, from January 2023 to October 2023, and randomly divided into two groups: 109 patients were treated with apheresis platelet transfusion (AP group) and 109 patients with buffy coat derived platelet concentrates (BC-PC group). Platelet counts were measured before and 24 hours after transfusion, and the corrected platelet ascending number (CCI) and platelet recovery rate (PPR) were calculated. The clinical efficacy and blood transfusion reaction were observed. After 24 hours of platelet transfusion, there was no significant difference in the platelet count between the AP and BC-PC groups (p > 0.05). However, CCI and PPR significantly differed between the two groups (p < 0.05). Moreover, the incidence of transfusion reaction in the AP group was significantly lower than in the BC-PC group. The clinical efficacy of buffy coat-derived platelet concentrates is lower than that of apheresis platelets, but it can also improve the patient's condition and quality of life. Therefore, clinicians could rationally use BC-PC, according to the actual situation of the patients.

Changes in inflammatory responses and autophagy during apheresis platelet preservation and their correlation with platelet transfusion refractoriness in patients with acute lymphoblastic leukemia.

Acute lymphoblastic leukemia (ALL) is a common hematopoietic malignancy, and platelet transfusion plays a crucial role in its treatment. This study aimed to investigate the changes in inflammatory response and autophagy during the preservation of apheresis platelets (AP) and their correlation with platelet transfusion refractoriness (PTR) in ALL. ALL patients were included, and APs were categorized based on the preservation period (day 0, day 1, days 2-3, and days 4-5). The activation factors procaspase-activating compound 1 (PAC-1) and P-selectin (CD62P), AP aggregation function, inflammation levels (interleukin 1 beta [IL-1β], interleukin 6 [IL-6], tumor necrosis factor alpha [TNF-α] and NOD-like receptor thermal protein domain associated protein 3 [NLRP3]), and autophagy-related genes (p62) during AP preservation were assessed. Following co-culturing APs with peripheral blood mononuclear cells (PBMCs), specific activation markers were studied to observe APs influence on immune cells activation. The effectiveness of platelet transfusion was assessed, and risk factors for PTR were analyzed. As the storage duration of AP increased, the activation factors, coagulation factor activity, inflammation levels, and the activation of immune cells in AP increased, while fibrinogen levels and AP aggregation function decreased. The expression levels of autophagy-related genes (the autophagy marker light chain 3B gene [LC3B] and Beclin 1 gene) decreased with prolongation preservation. The effective rate of AP transfusion in ALL patients was 68.21%. AP preservation time, IL-6, p62, and Beclin 1 were identified as independent risk factors affecting PTR in ALL patients. In conclusion, during AP preservation, inflammation, autophagy, and activation of immune cells were observed to increase. AP preservation time, IL-6, p62, and Beclin 1 were independent risk factors for PTR.

Impact of the COVID-19 pandemic on blood donation and transfusions in the United States in 2020.

Reports have suggested the COVID-19 pandemic resulted in blood donation shortages and adverse impacts on the blood supply. Using data from the National Blood Collection and Utilization Survey (NBCUS), we quantified the pandemic's impact on red blood cell (RBC) and apheresis platelet collections and transfusions in the United States during year 2020. The 2021 NBCUS survey instrument was modified to include certain blood collection and utilization variables for 2020. The survey was distributed to all US blood collection centers, all US hospitals performing ≥1000 surgeries annually, and a 40% random sample of hospitals performing 100-999 surgeries annually. Weighting and imputation were used to generate national estimates for whole blood and apheresis platelet donation; RBC and platelet transfusion; and convalescent plasma distribution. Whole blood collections were stable from 2019 (9,790,000 units; 95% CI: 9,320,000-10,261,000) to 2020 (9,738,000 units; 95% CI: 9,365,000-10,110,000). RBC transfusions decreased by 6.0%, from 10,852,000 units (95% CI: 10,444,000-11,259,000) in 2019 to 10,202,000 units (95% CI: 9,811,000-10,593,000) in 2020. Declines were steepest during March-April 2020, with transfusions subsequently rebounding. Apheresis platelet collections increased from 2,359,000 units (95% CI: 2,240,000-2,477,000) in 2019 to 2,408,000 units (95% CI: 2,288,000-2,528,000) in 2020. Apheresis platelet transfusions increased from 1,996,000 units (95% CI: 1,846,000-2,147,000) in 2019 to 2,057,000 units (95% CI: 1,902,000-2,211,000) in 2020. The COVID-19 pandemic resulted in reduced blood donations and transfusions in some months during 2020 but only a minimal annualized decline compared with 2019.

Efficacy and Safety of Decitabine Combined with Modified EIAG Regimen in the Treatment of Patients with Relapsed/Refractory Acute Myeloid Leukemia and High-risk Myelodysplastic Syndrome

To investigate the efficacy, prognosis and safety of decitabine combined with modified EIAG regimen in the treatment of patients with relapsed/refractory acute myeloid leukemia (AML) and high-risk myelodysplastic syndrome (MDS). The clinical data of 44 patients with relapsed/refractory AML and high-risk MDS admitted to our hospital from January 2017 to December 2020 were analyzed retrospectively. The patients were equally divided into D-EIAG group (decitabine combined with EIAG regimen) and D-CAG group (decitabine combined with CAG regimen) according to clinical treatment regimen. The complete response (CR), CR with incomplete hematologic recover (CRi), morphologic leukemia-free state (MLFS), partial response (PR), overall response rate (ORR), modified composite complete response (mCRc), overall survival (OS) time, 1-year OS rate, myelosuppression and adverse reactions between the two groups were compared. In D-EIAG group, 16 patients (72.7%) achieved mCRc (CR+CRi+MLFS), 3 patients (13.6%) achieved PR, and ORR (mCRc+PR) was 86.4%. In D-CAG group, 9 patients (40.9%) achieved mCRc, 6 patients (27.3%) achieved PR, and ORR was 68.2%. Difference was observed in mCRc rate between the two groups (P=0.035), but not in ORR (P>0.05). The median OS time of D-EIAG group and D-CAG group was 20 (2-38) months and 16 (3-32) months, and 1-year OS rate was 72.7% and 59.1%, respectively. There was no significant difference in 1-year OS rate between the two groups (P>0.05). After induction chemotherapy, the median time for absolute neutrophil count recovery to 0.5×109/L in D-EIAG group and D-CAG group was 14 (10-27) d and 12 (10-26) d, for platelet count recovery to 20×109/L was 15 (11-28) d and 14 (11-24)d, the median red blood cell suspension transfusion volume was 8 (6-12) U and 6 (6-12) U, and the median apheresis platelet transfusion volume was 4 (2-8) U and 3 (2-6) U, respectively. There were no statistically significant differences in comparison of the above indicators between the two groups (P>0.05). The hematological adverse reactions of patients were mainly myelosuppression. Grade III-IV hematological adverse events occurred in both groups (100%), with no increase in the incidence of non-hematological toxicities such as gastrointestinal reactions or liver function damage. Decitabine combined with EIAG regimen in the treatment of relapsed/refractory AML and high-risk MDS can improve remission rate, provide an opportunity for subsequent therapies, and have no increase in adverse reactions compared with D-CAG regimen.

Transfusion Effectiveness of Single Donor Apheresis Platelet over Random Donor Platelet; A Comparative Study

Background: Platelet transfusion performs a key function in treatment for patients with thrombocytopenia. The use of single donor apheresis platelet results in better post-transfusion recovery &amp; survival than random donor platelet. Activation of platelet depends on their preparation and storage and this may be one of the factors responsible for storage related change in platelet membrane proteins. In transfusion medicine laboratory we commonly prepare platelet concentrates from whole blood, platelet rich plasma, buffy coat and single donor plateletpheresis. Objective: The aim of the study was to evaluate the transfusion effectiveness of single donor apheresis platelet over random donor platelet. Methods: This is an observational study. This study was carried out on 125 dengue patients the find out about the population including male and female patients in the Department of Transfusion Medicine, Bangabandhu Sheikh Mujib Medical University, Chittagong Medical College Hospital, Bangladesh and Samorita Hospital &amp; Medical College, Dhaka, Bangladesh. The duration of the period from July 2021 to December 2022. The period from data was entered in MS Excel and Statistical analysis was done using SPSS-24. Results: The total study population was 125 patients aged 10 – 40 years, 17(13.6%) were ≤10 years, 49(39.2%) were 11-20 years, 37(29.6%) were 21-30 years and 22(17.6%) were 31-40 years. Sex distribution of the population where, 85(68.0%) were male and 40(32.0%) were female. Conclusion: Single-donor apheresis platelet transfusions produced higher platelet counts, whereas random donor platelet also effective in preventing hemorrhage.

Analysis of Related Factors of Adverse Transfusion Reactions

To investigate the related factors of adverse reactions of blood transfusion, and clinical precautions so as to reduce the adverse reactions. Data of 2108 patients with allogeneic transfusion in our hospital from January 2017 to June 2017 collected and analyzed. These patients received 15 244 time of blood transfusion, and 213 time of adverse reactions occurred in 178 patients in totality, the incidence is 1.4%, and there was no significant difference between the male (1.31%) and female (1.53%). The main type of transfusion reaction were allergy (73.23%), FNHTR (11.74%) and TACO (10.80%). Among all kinds of blood components, the incidence of adverse reactions of apheresis platelet transfusion was the highest (4.31%), significantly higher than that of cryoprecipitate and other blood components. The incidence rate of adverse reactions of blood transfusion in the hematopathy patients was 2.56%, significantly higher than that of immune diseases (1.48%), cancer diseases (1.28%) and other diseases (1.08%), (P＜0.01). The rate of transfusion history of apheresis platelets was 42.67% (the incidence of adverse reactions was 4.31%), significantly higher than other groups (P＜0.01); the rate of transfusion history of cryoprecipitate was 4.11% (the incidence of adverse reaction was 0.45%), significantly lower than other groups (P＜0.05). Among the disease types, the rate of transfusion history in the hematopathy patients was 48.79% (the incidence of adverse reaction was 2.56%), significantly higher than that of other groups (P＜0.01). The incidence of drug allergy in patients with the adverse reactions to blood transfusion was 11.25%, significantly higher than that of patients without adverse reactions (4.71%) (P＜0.01). The main risk factors of adverse reactions of blood transfusion are as follows: blood varieties, disease type, transfusion history and drug allergy history. For the patients with transfusion, multiple factors should be controlled, so as to reduce the adverse reactions.

COVID-19 transmission and blood transfusion: A case report

The recent outbreak of the novel coronavirus disease 2019 (COVID-19) has been labelled as a pandemic by the World Health Organization. Although person-to-person transmission of the etiologic agent, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been confirmed, it is not known whether COVID-19 may be transmitted by blood transfusion. Notwithstanding the urgent requirement of blood, it is critical to know whether the SARS-CoV-2 virus can be transmitted by blood transfusion because many individuals may be asymptomatic carriers and may donate blood. Several cases in which specific viral RNA could be detected in the serum from patients with COVID-19 have already been reported; these findings suggest that blood donation may be an unexplored route of transmission. However, the American Association of Blood Banks and Centers for Disease Control and Prevention have not recommended any specific SARS-CoV-2-related actions to be taken at blood collection centres at this time. In this report, we describe a case of a 21-year-old man with very severe aplastic anaemia who received apheresis platelet transfusion from an individual who was subsequently diagnosed with COVID-19. Our patient tested negative for COVID-19 and is awaiting allogeneic stem cell transplantation.

Clinical efficacy of platelet transfusion therapy in patients with leukemia and analysis of risk factors for ineffective transfusion.

Clinical efficacy of platelet transfusion therapy in patients with leukemia was investigated to analyze risk factors for ineffective transfusion. A total of 105 cases of patients with leukemia admitted to The First Affiliated Hospital of Bengbu Medical College from August 2016 to November 2018 were selected as research subjects. A total of 49 patients received transfusion of apheresis platelet suspension, and were group A. Fifty-six patients who received mixed multi-person platelet suspension were group B. The percentage plate recovery (PPR) and corrected count increment (CCI), interleukin-11 (IL-11) and soluble glycoprotein 130 (sgp130) levels were compared between the two groups, and the correlation of PPR and CCI with serum IL-11 and sgp130 levels was analyzed. Multivariate logistic regression was used to analyze the independent risk factors affecting ineffective transfusion in patients with leukemia. After transfusion, PPR and CCI in both groups were significantly higher than those before transfusion (P<0.05). IL-11 was significantly increased in both groups after transfusion, and sgp130 was significantly decreased in the two groups after transfusion (P<0.05). Serum IL-11 level in leukemia patients was positively correlated with PPR and CCI (r=0.7693, P<0.001), (r=0.7760, P<0.001), and serum sgp130 level in leukemia patients was negatively correlated with PPR and CCI (r=-0.7086, P<0.001), (r=-0.7733, P<0.001). There were differences between the effective group and the ineffective group in transfusion frequency, fever, infection and splenomegaly (P<0.05). Fever (OR, 0.382; 95% CI, 0.183-0.972) and infection (OR, 0.367; 95% CI, 0.140-0.956) were independent risk factors for ineffective transfusion. In conclusion, apheresis platelet or mixed multi-person platelet suspension transfusion can significantly improve the disorder of platelet count in patients with leukemia, and improve the clinical efficacy. Fever and infection are independent risk factors leading to ineffective transfusion.

Efficacy of cross-match compatible platelets in multi transfused haemato-oncology patients refractory to platelet transfusion

BackgroundPlatelet refractoriness, which leads to platelet transfusion failure resulting in significant morbidity and long hospital stay, is routinely not investigated. AimsTo determine the efficacy of cross-match compatible platelets in multi-transfused alloimmunized hemato-oncological patients refractory to platelet transfusion. Materials and method149 ABO compatible single donor apheresis platelet transfusions given to 38 alloimmunized refractory patients. Corrected Count Increment (CCI) <5000 (1 h) was taken to define refractoriness. Solid-phase red cell adherence assay was used to determine the alloimmunization status and platelet cross-matching. Post Transfusion Platelet Increment, CCI and the Percentage Platelet Recovery were used to monitor the effectiveness of platelet transfusion. ANOVA test followed by Post hoc test Tukey HSD used to compare group means and classified into three groups depending upon the cross-matching and compatibility status. Categorical data was analysed for various outcomes using Pearson's chi square test or Fischer exact test. ResultPatients showed statistically significant recovery in terms of PPI, CCI and PPR at 1 h post SDAP transfusions when they received cross-matched compatible platelets. The one-hour CCI was significantly higher for cross-match-compatible platelets (19173 ± 2692) than for incompatible (5888 ± 1526) and for uncross-matched (8140 ± 1480). Forty four (97.8%) of 45 cross-matched compatible platelet transfusion episodes showed a satisfactory response in terms of PPI and CCI values as compared to 50 % and 53.9% in uncross-matched group respectively (p < 0.0001). ConclusionPlatelet cross-matching is an effective intervention in the management of multi-transfused alloimmunized Haemato-oncological patients, refractory to platelet transfusion.

The description of corrected count increment on one hour and 24 hours after platelet apheresis transfusion in Sanglah General Hospital Denpasar

Introduction: Evaluating the response after platelet transfusion is vital to measure the success rate of the therapy and plan the subsequent management of patients. The evaluation can be done by calculating the corrected count increment (CCI) at 1 hour and 24 hours after transfusion. The purpose of this study was to determine the therapeutic response to apheresis platelet transfusion by measuring the CCI at 1 hour and 24 hours after transfusion.Methods: This study was a cross-sectional descriptive study of patients who received apheresis platelet transfusions. In total, 35 samples were examined for platelet counts before and after transfusion. The CCI was measured at 1 hour and 24 hours after transfusion. Descriptive statistical analysis was performed to calculate the percentage and mean count.Result: The mean count of transfused platelets was 2.7 × 10¹¹ / unit. The mean platelet count before transfusion was 18.5 × 10³ / μL. The mean platelet increment at 1 hour was 25.4 10³ / μL and 24 hours was 22.6 × 10³ / μL. The mean CCI ± SD at 1 hour and 24 hours was 15,036.63 ± 13,709.73 and 13,625.60 ± 13,580 respectively. A total of 63% of samples reached the target CCI at the 1-hour measurement, while the remaining 37% did not. Meanwhile, 60% of the samples reached the CCI target at the 24-hour measurement, while 40% did not.Conclusion: The response to apheresis platelet transfusion by measuring the CCI reached the target in 63% of patients at 1 hour after transfusion and 60% of patients at 24 hours after transfusion.

Analisis Corrected Count Increment (CCI) pada penderita post transfusi trombosit apheresis di RSUP Dr. Wahidin Sudirohusodo, Makassar, Indonesia

Background: Platelet refractoriness is a problem in the implementation of platelet transfusion. It is a lack of increased platelets after platelet transfusion. This study aimed to analyze the increase in platelet counts of patients who received apheresis platelet transfusion by using Corrected Count Increment (CCI) formula at Dr. Wahidin Sudirohusodo General Hospital Makassar.Methods: This was an observational cross sectional study with 242 thrombocytopenia patients. The success of platelet transfusion was calculated using the CCI formula with CCI values after transfusion of 4.5 x 109/L at 24 hours post transfusion. Statistical analysis used chi square, t-independent, and spearmen’s correlation test, with significant test results if p-value was &lt; 0.05.Results: An average increase of platelet counts was 28.5 x 109/L. Successful thrombocyte transfusion was found in 107 subjects (44.2%) and unsuccessful in 135 subjects (55.8%). The proportion of successful transfusion was found to be higher in men (45.5%) than women (43.2%), however, it was not significant (p &gt; 0.05). There was a significant relationship between young age and successful thrombocyte transfusion (p &lt; 0.001). Unsuccessful transfusion rate was high in cases of malignancy, infection, bleeding, and metabolic disease (p &lt; 0.05).Conclusions: There was a significant negative correlation between age and CCI, older age presented lower value of CCI. Characteristics of disease affected the successful of apheresis thrombocyte transfusion.

One-unit compared to two-unit platelet transfusions for adult oncology outpatients.

Platelet dosing has been studied in adult oncology inpatients, but there is almost no published evidence to guide platelet dosing for adult outpatients. We evaluated transfusion indices after 1 unit and 2 unit apheresis platelet transfusions at our hospital to determine whether a benefit to 2-unit transfusions could be detected. A retrospective chart review was conducted of all adult oncology patients who received an outpatient platelet transfusion over a 16-month period (July 2016-November 2017). Pre- and post-transfusion platelet count, and chronology of subsequent platelet transfusions were compared. A total of 8467 platelet transfusions were administered to 602 patients during the study period. 59·8% of patients (n=360) were transfused interchangeably with one or two platelets throughout the study period. The primary study population were comprised of these patients. On average, a 2-unit platelet transfusions resulted in a higher immediate post-transfusion platelet count (43 vs. 37x103 /μl, P<0·001) and a lower corrected count increment (9707 vs. 14060, P<0·001). Transfusion with 2 platelets did not increase the number of days between outpatient transfusions (median; 4 vs. 4, P=0·959) or the platelet count at the time of next transfusion (11 vs. 11x103 /μl, P=0·147). Among adult, oncology outpatients that were transfused interchangeably with one or two units of platelets, transfusion with two platelets did not offer a durable improvement in platelet count or impact the subsequent transfusion schedule.

HLA Class I Alloimmunization and Platelet Transfusion Support in HLA-Identical Bone Marrow Transplant for Sickle Cell Disease: A Sickle Transplant Alliance for Research Study

Introduction: HLA alloimmunziation has been described in patients, including pediatric patients with sickle cell disease (SCD), who received only leukocyte-reduced red blood cell (RBC) transfusions. While HLA alloimmunization has significant implications in bone marrow transplant (BMT) with an HLA-disparate donor (donor-specific HLA antibodies increase the risk of graft rejection), the clinical significance of this alloimmunization in HLA-identical BMT is unclear. In particular, it is unknown whether HLA class I alloimmunization affects platelet transfusion support during BMT. Platelet transfusions are especially important in BMT for SCD because of the historic high incidence of intracranial bleeding and the subsequent adoption of a relatively high platelet transfusion threshold.Methods: We tested for HLA class I alloimmunization using pre-BMT serum or plasma from 32 pediatric patients with SCD undergoing BMT with an HLA-identical sibling donor. HLA class I alloimmunization was evaluated using the FlowPRA® (panel reactive antibody) screening test which detects IgG antibodies to the majority of HLA class I antigens. Pre-BMT, patients had received leukocyte-reduced RBC transfusions. All patients undergoing BMT received leukocyte-reduced, irradiated, apheresis platelet transfusions to maintain a platelet count greater than 50 x 109/L. The number of platelet transfusions received in the first 45 days post-BMT was compared between those with a positive PRA versus those with a negative PRA using a two-sample t-test.Results: Among the 32 patients studied, the mean age at BMT was 9.4 years (range 1-21 years). Pre-BMT, 40% had received greater than 10 RBC transfusions and 32% of the entire cohort was receiving chronic RBC transfusions. BMT conditioning regimens included: traditional myeloablative busulfan, cyclophosphamide, antithymocyte globulin (BU-CY-ATG) (n=10); dose-reduced BU-CY-ATG + fludarabine (flu) (n=16); reduced intensity conditioning (RIC) alemtuzumab, flu, melphalan +/- thiotepa (n=5); and RIC BU-flu-ATG (n=1). All patients received HLA-identical sibling donor bone marrow, with 3 patients receiving a combined bone marrow and cord blood graft. All patients engrafted with 100% survival at day +45. Six patients developed acute graft-versus-host disease (GVHD): 1 grade I, 3 grade II, 1 grade 3, 1 grade 4. No patient had an intracranial bleed or other serious bleeding.From testing of the pre-BMT sample, 11/32 (34%) of patients had a positive HLA class I antibody screen. HLA class I alloimmunized patients received significantly more platelet transfusions than non-alloimmunized patients: mean 19.2 (SD 13.9) vs. 11.2 (SD 8.0) transfusions, p=0.049 (Figure). On univariate analysis, age, sex, conditioning regimen, and GVHD were each not significantly associated with the number of platelet transfusions (p>0.1). Only two patients developed hepatic sinusoidal obstruction syndrome (one HLA alloimmunized patient, one non-alloimmunized patient). Mean day of platelet engraftment was not significantly different between alloimmunized compared to non-alloimmunized patients: day +34.6 (SD 10.6) vs. day +30.2 (SD 11.3), p=0.28. Among HLA class I alloimmunized patients, the mean positive PRA was 19.7% (range 4-55%); there was no association with this PRA value and the number of platelet transfusions (r2=0.0064, p=0.81).Conclusion: In pediatric HLA-identical sibling BMT for SCD, pre-BMT HLA class I alloimmunization (but not the absolute PRA value) appears to be associated with more platelet transfusions. It is unclear if this increased platelet transfusion requirement is due directly to HLA antibody immune-mediated clearance of transfused platelets or other inherent differences of HLA class I alloimmunized patients. [Display omitted] DisclosuresQayed:Novartis: Consultancy.

The epidemiology of bacterial culture-positive and septic transfusion reactions at a large tertiary academic center: 2009 to 2016.

Bacterial contamination and associated septic transfusion reactions (STRs) remain the leading infectious risk to the blood supply. We sought to characterize the risk and clinical presentation of blood culture-positive transfusion reactions (BCPTRs) and STRs at our institution. A retrospective analysis was conducted of all suspected transfusion reactions reported to the transfusion service at a 1000-bed tertiary academic medical center from January 2009 to September 2016. Routine investigation included review of the clinical presentation, Gram stain, and bacterial culture of residual blood from the transfused product or associated blood bag. BCPTRs were defined by the presence of a positive bacterial culture in the blood product and/or recipient. STRs met definitive Centers for Disease Control and Prevention hemovigilance criteria for transfusion-transmitted infection, with definite imputability and concordant bacterial culture of the blood product and recipient. A total of 688,514 blood products were transfused during the study period, 3170 transfusion reactions were reported, and 18 (0.57%) were BCPTRs of which seven (0.22%) were STRs. Fifteen of 18 (83.3%) BCPTRs and six of seven (85.7%) were associated with transfusion of apheresis platelets. Major symptoms and signs of BCPTRs included chills (67%), fever (61%), and nausea and vomiting (50%). Four of seven (57.1%) STRs were classified as severe or life-threatening. BCPTRs are rare yet potentially serious. The signs and symptoms of BCPTRs, and associated STRs, are not specific, posing risk of misclassification. Challenges surrounding reporting and case ascertainment underscore the need for laboratory measures to address residual risk of contamination.

Platelet Survival in Hematology Patients Assessed by the Corrected Count Increment and Other Formulas.

To compare the performance of the corrected count increment (CCI) and three other formulas to assess 24-hour posttransfusion platelet survival in hematology patients. Twenty-four-hour posttransfusion platelet counts were analyzed after apheresis platelet transfusion. Platelet increment (PI), percent platelet recovery (PPR), and percentage platelet increment (PPI) were compared with CCI by receiver operating characteristic analysis. Clinical factors that influence platelet survival were assessed by logistic regression. In total, 142 apheresis platelet transfusions in 85 hematology patients were studied. Mean (SD) CCI at 24 hours was 11,869 (10,125). Compared with CCI, the sensitivity of other formulas ranged from 89.4% to 95.7% and specificity from 94.7% to 100%. Cutoff values were 15.7 × 103/µL for PI, 11.4% for PPR, and 17% for PPI. For ABO-compatible vs incompatible transfusions, CCI was 14,070/µL vs 9,176/µL (P = .007). Negative factors for all formulas were sepsis, hypotension, and amphotericin B. PI, PPR, and PPI are comparable to CCI for assessing 24-hour platelet survival.

Acute Hemolytic Transfusion Reaction in Group B Recipient Associated with Group A Apheresis Platelet Donor: Case Report and Literature Review

Acute hemolytic transfusion reaction is a known but rare potential adverse event related to platelet transfusion. Most reported cases of platelet-related hemolytic transfusion reaction have resulted from transfusion of platelets from group O donor to group A recipient. We identified only one prior case report in the literature of hemolytic transfusion reactions resulting from transfusion of apheresis platelets from group A donor to group B recipient. In that case report, two platelet units were obtained from a single donation and transfused into two separate patients. Both patients exhibited acute hemolytic reactions. The donor is reported to have high anti-B titers, as well as report of probiotic use. We report a case of acute hemolytic reaction in group B recipient following transfusion of apheresis platelets from group A donor with high-titer anti-B but unknown status of probiotic use. This case demonstrates that while low, there still exists potential risk for hemolysis from out-of-group A plasma transfusion.

Immature Platelet Count Levels as a Novel Quality Marker in Plateletpheresis.

The efficiency of plateletpheresis was improved owing to new developments in automated cell separators in the past decades. Nowadays multiple units of plateletpheresis products can be taken per collection from single donor and new parameters such as immature platelet fraction (IPF), immature platelet count (IPC) can be detected practically by automated hematology analyzers. Our aim is to find out a new quality parameter for evaluation of plateletpheresis by analyzing the platelet indices of donor and also to predict platelet recovery in recipients thereby preventing unnecessary platelet transfusion. In this study 104 platelet apheresis procedures were performed on the Trima Accel cell separator. Complete blood counts of donors and recipients were analyzed by Sysmex XN-1000 automated blood cell counter by means of quality parameters such as platelet count, IPF, IPC, mean platelet volume, platelet distribution width. We analyzed these parameters in the follow up after the transfusion of plateletpheresis and evaluated them as quality markers in the assessment of plateletpheresis effectiveness. For recipients of both single and double unit apheresis platelet transfusions, the pre-apheresis donor IPC correlated significantly with 1st and 24th hour recipient IPC values (p values < 0.05 for all comparisons). A-IPC as well as % change in IPF can be used to determine the quality of plateletpheresis in conjunction with platelet number in terms of evaluation of donors and also in the follow up of recipients undergoing platelet transfusion.