Transfusion最新文献

Background: Plerixafor is an adjunct peripheral blood stem cell (PBSC) mobilization agent with well-demonstrated safety and efficacy. The routine use of the originator brand drug (Mozobil) has been limited by cost. This retrospective study was conducted to compare the mobilization efficacy of a lower-cost generic plerixafor and Mozobil in multiple myeloma (MM) patients.

Study design and methods: The study included two near-concurrent cohorts of MM patients mobilized with brand (n = 64) or generic (n = 61) plerixafor in addition to filgrastim. Collection and early engraftment outcomes were compared.

Results: The two cohorts had comparable distributions of sex, age, and weight. Previous treatment histories and proportions of upfront versus just-in-time plerixafor use were similar. There was no significant difference in their median overall cumulative total yield (10⁶ CD34+ cells/kg) (brand, 5.91; generic, 5.80; p = .51). However, the generic cohort had a significantly higher median yield after the first dose (4.79 vs. 3.78, p = .03), and consequently lower median numbers of plerixafor doses (p = .001) and collection days (p = .002). Only 31.1% of patients in the generic arm required more than one dose versus 59.4% of patients in the brand arm (p = .006). All transplanted patients in the brand and generic arms (90.6% and 85.2% respectively, p = .42) achieved engraftment. There was no significant difference in their median times to platelet and neutrophil engraftment, nor their transfusion requirements during the first 30 days post-transplant.

Conclusion: The generic plerixafor produced comparable cumulative collection yields and early engraftment outcomes as Mozobil, but fewer doses and collection days were needed to reach collection goal.

Background: Red cell concentrates (RCCs) may be cryopreserved at Canadian Blood Services (CBS) for up to 10 years; however, inadvertent warming of these units over the prescribed storage temperature (≤ -65°C) may occur. These units may be discarded from inventory to avoid potential adverse transfusion outcomes. This study aimed to assess the quality of RCCs that experienced unintentional transient warming events (TWEs) related to freezer failures.

Study design: Thirty cryopreserved RCCs with known TWEs were selected for this study and classified into three different experimental groups (Event 1 (n = 5) TWE > -65°C for 34 min; Event 2 (n = 23) TWE > -65°C for 48 h; and both Event 1 and Event 2 (n = 2) TWE > -65°C for 34 min and 48 h). Ten additional RCCs with no known TWEs, cryopreserved over the same period, were selected as controls. Thawed RCCs were deglycerolized using the Haemonetics ACP 215, and in vitro quality was assessed throughout hypothermic storage.

Results: RCCs from the control and all three experimental groups met the Canadian Standards Association (CSA) guidelines for hematocrit, total hemoglobin, and hemolysis at expiry. RCCs experiencing a singular TWE had similar in vitro quality to control RCCs.

Discussion: This study's findings revealed that single exposures to specific documented TWEs did not significantly impact the quality of RCCs post-deglycerolization. While units should still be assessed on a case-by-case basis upon TWE, our work provides the first-ever evidence that supports a broader policy of unit retention by blood centers.

Background: Previous reports suggest that blood donors have a lower mortality risk, which may partially reflect the "healthy donor effect" (HDE). HDE arises in donors due to selection bias and confounding if not appropriately addressed.

Study design and methods: Using the Sax Institute's 45 and Up Study data linked with blood donation history, we used a "5-year exposure window" method to select donors into regular high-frequency whole blood (WB)donors (at least two donations per exposure year) and low-frequency donors (remaining donors) with an active donation career of 5 years. To further reduce the confounding, we used statistical approaches like the inverse probability weighted (IPW) marginal structural model and the doubly robust targeted minimum loss-based estimator (TMLE), which incorporated machine learning algorithms and time-varying analyses.

Results: We selected 4750 (64.7%) low-frequency and 2588 (35.3%) high-frequency donors in the analyses. A total of 69 (1.5%) from the low-frequency and 45 (1.7%) donors from the regular high-frequency group died during the 7-year follow-up period. We did not find any statistically significant association between regular high-frequency blood donation and mortality (IPW RR = 0.98 95% CI 0.68, 1.28). TMLE model also showed similar results to IPW (RR = 0.97 95% CI 0.80, 1.16). Time-varying TMLE did not find any significant association between high-frequency donation and all-cause mortality either (RR = 0.98 95% 0.74, 1.29).

Conclusions: We did not find a significant association between regular high-frequency WB donation and all-cause mortality when appropriate methods were employed to minimize the HDE.

Background: Some patients express concerns regarding receipt of allogeneic blood transfusions from donors potentially vaccinated against SARS-CoV-2 (COVID-19). However, limited information exists about patients' expression of these concerns or how to address them during the blood transfusion consent process. In this study, we describe our experience of working collaboratively with patients with vaccine-related transfusion concerns prior to elective surgery, summarizing treatment decisions and clinical outcomes.

Study design and methods: This observational descriptive study includes patients seen in our Bloodless Medicine and Surgery clinic between June 2022 and June 2024 for vaccine-related transfusion concerns prior to elective surgery. A shared decision-making framework was employed to foster conversation, share information, provide reassurance, reconcile conflict, and match preferences with available care options. Patient characteristics, treatment decisions, and surgical outcomes were reviewed and summarized.

Results: Thirty-five patients were included, with median (1st, 3rd quartile) age of 61 (53, 69) years. Cardiac surgery was the most common type of surgery (29%). Twelve patients (34%) were anemic preoperatively, and all received preoperative treatment. After discussion with a Bloodless Medicine specialist, 24 (68.6%) decided to consent to the use of all blood products, 5 (14.3%) accepted only red blood cells, and 6 (17.1%) declined all blood products. Among 28 patients undergoing surgery, only 4 (14%) received allogeneic transfusion perioperatively.

Conclusion: Many patients concerned about the vaccination status of blood donors may ultimately consent to allogeneic blood products after shared decision-making with a Bloodless Medicine specialist, highlighting the importance of patient empowerment and collaborative care.

Background: Transfusion-transmitted malaria (TTM) is rare in non-endemic areas (non-EAs) but can potentially be fatal. This review analyzes the laboratory results of donors causing TTM in non-EAs, to assess the detectability of their Plasmodium infection by molecular or antibody tests.

Study design and methods: TTM cases in the United States, Canada, and Europe since 2010 were identified through a literature review. Authors and laboratories were contacted for missing details about sample types and laboratory methods. Results of Plasmodium polymerase chain reaction (PCR) and antibody tests were summarized.

Results: Twelve cases of TTM and one bone marrow transplant transmission were identified. Of the 13 source donors, 12 were tested by PCR, 10 were positive on at least one sample; the 2 negative donors were tested only on retained segments of blood refrigerated for several weeks. All donors were PCR positive on a fresh sample except one who was positive on a retained but not a fresh sample. These PCRs targeted Plasmodium DNA with sensitivities in the range of 1000-10,000 parasites/mL. Antibody EIA was positive in only three of seven donors tested.

Discussion: This review found that antibody EIAs failed to detect four of the seven TTM donors tested. DNA-based PCRs were able to detect Plasmodium infection in all donors tested except for two tested only on samples likely to have deteriorated from prolonged storage. Recently developed ribosomal RNA-based molecular donor screening assays are approximately 1000 fold more sensitive than these DNA-based PCRs, holding promise as a potential method to further reduce TTM.

Background: Transfusion-transmissible infection (TTI) prevalence among US blood donors has been widely documented. Here we estimate the prevalence of donors presenting with ≥2 TTIs (multiple infections past or present referred to as coinfections) and describe their demographics and associations.

Methods: Data from the Transfusion-Transmissible Infections Monitoring System were compiled for October 2020-September 2023 (3 years). Prevalence per million donations (pmd) was calculated for each TTI coinfection combination with demographic characteristics summarized. The odds of each TTI coinfection combination were estimated using logistic regression. Reactivity by NAT and/or serology (HIV, HBV, and HCV) defined donors as consensus positive (CP) for each infection while serology-based algorithms defined syphilis CP and the subset with active syphilis infections (ASIs).

Results: About 22 million donations were included, with 212 coinfections (9.7 pmd). Around 2% of donations positive for any TTI (n = 10,516) were coinfections. Coinfection prevalence per TTI combination ranged from 0.3 pmd for HIV CP and HCV CP, to 4.3 pmd for HIV CP and syphilis CP. There were high proportions of coinfections from donors who were male, aged 25-54 years, white or black, first time, and residing in the southern US Census Region. The odds of a second TTI occurring in an individual donor with a TTI ranged from 23 (95% CI: 13, 41) times more likely for HBV CP and ASI to 395 (95% CI: 298, 524) times more likely for HIV CP and ASI.

Conclusions: Coinfections are relatively uncommon among blood donors in the United States; however, associations exist among HIV, HBV, HCV, and syphilis infections.

Correlations between allergic transfusion reactions (ATRs) and allergic predisposition to food and inhaled allergens have been consistently reported. Food or pollen allergens circulating in the blood can be indirectly identified using the basophil activation test. In some cases, food or pollen allergens have been identified in transfused blood products that cause ATRs.

Background: Splitting apheresis platelet (PLT) units increase available inventory during shortages. The impact of prolonged storage in gas-impermeable aliquot bags on PLT quality in vitro and transfusion outcomes in patients remains uncertain.

Study design and methods: We assessed in vitro PLT quality and thromboelastography (TEG) in PLTs stored for 8 or 24 h in aliquot bags compared with baseline (T0). Retrospective assessment of response (PLT increment and corrected count increment (CCI)) was conducted among adults (≥18 years) transfused with split platelet units from January 2021 to June 2022.

Results: No differences were observed in PLT and white blood cell (WBC) counts, mean platelet volume, or TEG parameters during storage, except for an increase in TEG R time (mean ± SD) at 24 h (6.1 ± 0.5 min) compared to T0 (4.4 ± 0.8 min), p = 0.0031 one-way ANOVA. Eighty-one patients were transfused 119 split units with a median [IQR] PLT yield of 2.1 × 10¹¹[1.9 × 10¹¹ to 2.3 × 10¹¹] and storage duration of 1.6[0.7-9.1] h. The overall median PLT count increment was 6.0 × 10³/uL and CCI was 5.0 × 10³, correlating negatively with split unit storage duration (Spearman rho = -0.218, p = 0.017). Compared with split transfusions of pathogen-reduced (PR) PLTs, non-PR splits were associated with higher median platelet count increments (7.0 × 10³/μL vs. 4.0 × 10³/μL, p = 0.0263 Mann-Whitney U) and higher CCIs (6.5 × 10³ vs. 3.9 × 10³, p = 0.0116 Mann-Whitney U) despite no differences in PLT yields (2.1 × 10¹¹/μL vs. 2.1 × 10¹¹/μL).

Discussion: Storing PLTs in aliquot bags for 8 or 24 h does not adversely affect their quality in vitro. Splitting apheresis PLTs are feasible for adult transfusions during shortages. It may be advisable to prioritize non-PR PLTs for splitting given improved patient responses.

Background: Pathogen reduction technology (PRT)-treated apheresis platelets (APs) were returned without platelet swirl and with pH_22°C < 6.2. The platelet donor was taking prescription levothyroxine and metformin plus over-the-counter medications and supplements. We hypothesized that either PRT or medication was causative.

Study design and methods: One AP from a double AP collection from this donor was PRT-treated, the other unit untreated. Units were assessed over 7-day storage with a standard panel of platelet assays and metabolomics using high resolution mass spectrometry. The dose effect of metformin on platelets over storage was evaluated in vitro using APs obtained from non-medicated donors.

Results: This donor's PRT- and non-PRT treated paired units had pH values <6.2 by the end of day 2. Lactate generation rates in the PRT- and non-PRT units were very high compared to previously reported values and approached that reported for anaerobic storage. Metabolomic analysis revealed impairments in a number of energy metabolic pathways between PRT- and non-PRT platelets; however, this did not support a major causative role of PRT in the significant upregulation of lactic acid production. Metformin caused a dose-dependent upregulation of glycolysis, resulting in pH decline.

Discussion: We conclude that metformin is the most likely cause for this donor's stored platelet pH failures. Metformin is commonly used to treat type 2 diabetes and is not a donor deferral medication. Further investigation is indicated into the potential impact of metformin on platelet storage characteristics, the potential implications for medication deferral, and the need for additional screening tools in the laboratory.