Vox Sanguinis最新文献

Background and objectives: The administration of anti-D immunoglobulin achieved a significant reduction in the mortality of haemolytic disease of the foetus and the newborn due to RhD sensitization. Between 30% and 40% of this group of pregnant women, carriers of an RhD-negative foetus, would unnecessarily receive a high-cost drug, exposing them to the risks of a blood derivative. The aim of the study was to assess the accuracy of non-invasive foetal RhD genotyping at different weeks of pregnancy, to allow it to be used to determine appropriate anti-D administration.

Materials and methods: In this cross-sectional cohort study of foetal RhD genotyping, determined from cell-free foetal DNA (cffDNA) between weeks 8 and 30 of gestation, 270 samples from RhD-negative pregnant women were examined. Foetal Rh status was determined by multiplex PCR in real time, to detect targeting exons 5, 7, and 10 of the RHD gene and the SRY gene (a Y-chromosome-specific marker used to confirm male foetal sex).

Results: The performance diagnostic of the foetal RhD screen test offered a sensitivity of 100% (95% confidence interval [CI]: 98.03%-100%), a specificity of 100% (95% CI: 96.3%-100%) and an accuracy of 100%. The prevalence of RhD-negative newborns in RhD-negative pregnant women was 32.5%.

Conclusion: The results of the study reveal that the strategy of combining three RhD exons to determine foetal RhD status is reliable, with 100% accuracy. Prenatal diagnosis showed that 32.5% of newborns were RhD negative. Using this strategy, a decrease in the use of anti-D immunoglobulin is expected.

Background and objectives: DEHT is considered a safer alternative to DEHP, a commonly used plasticizer with potential toxicological risks. We aimed to compare the storage efficacy of red blood cells (RBCs) in DEHT bags containing two different additive solutions: SAGM and PAGGSM. A second objective was to evaluate the effect of transport/later processing in France (Etablissement Français du Sang [EFS]) on Day 1 versus early processing/transport in Belgium (Service Francophone du Sang [SFS]) on Day 0 before storage on the quality of blood components.

Materials and methods: RBC quality, including haemolysis and supernatant metabolic parameters, as well as plasma quality parameters, was measured over a period of 49 days and 2 years for RBC and plasma, respectively.

Results: RBCs stored in DEHT/PAGGSM bags showed superior quality preservation compared to those stored in DEHT/SAGM bags, with lower haemolysis rates (p < 0.01 for EFS and p < 0.05 for SFS) at the end of storage and better preserved adenosine triphosphate (ATP) levels over time at the EFS site (p < 0.01). No significant differences were observed in the measured plasma quality parameters.

Conclusion: DEHT blood bags combined with PAGGSM additive solution are a promising and safer alternative to DEHP/SAGM bags for RBC storage. The DEHT/PAGGSM combination results in improved preservation of RBC quality and stores plasma units adequately, compared to the DEHT/SAGM combination. Our take-home message is that processing and transport times which mimic routine practices for blood centres that are distant from collection sites do not affect the quality of blood components stored in DEHT.

Background and objectives: Arbovirus infections are a major public health concern in Brazil and an ongoing blood safety concern. Periodic outbreaks of such infections are common in the general population. This study aimed to establish the rates of dengue, chikungunya and Zika virus (DENV, CHIKV, ZIKV) RNAemia among blood donors at six public blood centres during the 2019-2020 and 2020-2021 outbreak seasons.

Materials and methods: Residual minipool samples from nucleic acid testing (NAT) screening for human immunodeficiency virus, hepatitis B virus and hepatitis C virus were further pooled to form pools of 18 donation samples and tested using a Grifols research-use-only triplex transcription-mediated amplification assay for DENV, CHIKV and ZIKV RNA to establish the rates of RNAemia and infection incidence. We used these rates and estimated the durations of RNAemia, juxtaposed with public health reporting of cases.

Results: A total of 5,616 minipools representing 101,088 donations were tested. During both outbreak seasons, the highest rates of DENV RNAemia were observed in Ribeirão Preto, at 122/100,000 donations (95% confidence interval [CI]: 66-224) and 100/100,000 (95% CI: 52-189), respectively, with DENV RNAemia also detected in São Paulo, Recife and Manaus in the 2019/2020 season and in the latter two during the 2020/2021 season. CHIKV RNAemia was detected in Recife and ZIKV RNAemia in Manaus during the 2020/2021 season. The estimated numbers of DENV, CHIKV and ZIKV RNAemic components released for transfusion over the study period were 338, 22 and 6, respectively.

Conclusion: Surveillance for arbovirus RNAemia in blood donors is a useful adjunct to public health surveillance, particularly when surveillance systems are under strain, and has implications for transfusion safety.

Background and objectives: The number of critically ill patients with haematological conditions is increasing, yet transfusion practices in this population remain poorly defined. This study aimed to compare transfusion strategies in critically ill patients with versus without haematological conditions.

Study design and methods: This international, prospective observational substudy of the International Point Prevalence Study of Intensive Care Unit [ICU] Transfusion Practices (InPUT) evaluated transfusion use in ICU patients with and without haematological conditions, including benign or malignant diseases or a history of stem cell transplantation. Outcomes included use of red blood cells (RBCs), platelets, plasma, haemostatic interventions, transfusion indications and thresholds.

Results: Of 3643 ICU patients, 131 (3.6%) had a haematological condition. These patients were more likely to receive RBC (odds ratio [OR] 1.58, 95% confidence interval [CI] 1.09-2.29) and platelet transfusions (OR 8.32, 95% CI 5.09-13.6), primarily due to low haemoglobin rather than physiological triggers. Platelet thresholds were lower (median 23 × 10⁹/L vs. 64 × 10⁹/L) compared to non-haematology patients. Both platelet and plasma transfusions were more frequently administered prophylactically rather than for active bleeding. Haemostatic interventions were more often used in haematology patients, at higher doses and typically without viscoelastic testing. Transfused haematology patients had higher 28-day mortality and longer ICU stays.

Conclusion: ICU patients with haematological conditions receive transfusions differently, particularly regarding platelet and plasma use. These findings underscore the need for prospective studies to define optimal transfusion thresholds in this growing and vulnerable patient population, although the study's limited sample size and lack of diagnostic granularity may affect interpretation.

Background and objectives: According to the World Health Organization, more than 1 billion people are at risk of leishmaniasis in over 89 countries. Environmental changes such as deforestation, urban expansion and climate change facilitate the spread of sand fly vectors and reservoirs, increasing disease transmission. The introduction of Leishmania into non-endemic regions may be further driven by globalization and ecotourism. Transfusion transmission, particularly of Leishmania infantum, remains a concern due to the parasite's ability to survive under blood storage conditions and its prolonged latent phase. We aimed to determine the prevalence of Leishmania spp. among blood donors in a non-endemic region.

Materials and methods: A prospective, cross-sectional study was conducted with 5145 blood donor samples collected from January to December 2023. Serological screening was performed using an in-house immunoglobulin G (IgG) ELISA based on Leishmania chagasi antigen. Samples with positive or inconclusive ELISA results were further tested by real-time PCR targeting internal transcribed spacer (ITS) and kinetoplast DNA (kDNA) regions, according to Pirmez et al. RESULTS: Among samples tested, 2.82% (141/5145) were ELISA-reactive. None of these were positive by PCR for ITS or kDNA.

Conclusion: The absence of Leishmania DNA in ELISA-reactive samples highlights the limitations of serological screening in low-endemicity areas. Inflammatory physiological conditions, such as pregnancy and abortion, may contribute to non-specific reactivity. The incorporation of molecular methods and the adoption of universal leukoreduction are recommended measures to ensure transfusion safety and avoid unnecessary donor deferrals.

Background and objectives: Severe dry eye disease is a commonly diagnosed condition that can be treated with serum eye drops (SEDs). SEDs are manufactured from the serum obtained from whole-blood donation. Patient information provided with SEDs has not been evaluated so far. This study aims to understand patients' views on SED materials and identify possible improvements.

Materials and methods: The study period was between 1 November 2021 and 30 June 2022. Eligible patients were supplied with either autologous SED (AutoSED) or patient-tailored (allogeneic) SED (PT SED) manufactured by Australian Red Cross Lifeblood. Patients were invited to participate via email or post and completed an online survey or participated in a semi-structured telephone interview.

Results: A total of 64 patients supplied with AutoSED and 18 with PT SED completed the survey, of whom 10 and 8, respectively, were interviewed. More AutoSED (89.1%) than PT SED (58.8%) patients reported that the instructions on the carton were helpful. More AutoSED patients (78.1%) than PT SED (55.6%) reported receiving the SED brochure and that the information was easy to understand. Information on how to dispose the eye drops and the risk of treatment was easy to understand. Sixteen patients reported accessing the quick-response code to view the SED video and indicated that it was easy to understand.

Conclusion: Patient views on the materials provided with SEDs were generally positive. Suggested improvements included changing the location of sealing stickers on the carton, providing further detailed information on shelf-life after power supply challenges and natural disasters and storage and handling during travel.

Background and objectives: It remains unclear whether sleep deprivation and fasting increase the risk of vasovagal reactions (VVRs) in blood donors. This study explored this question.

Materials and methods: A large observational study was conducted in a regional blood centre handling 309,971 blood donations from 83,709 donors between 2017 and 2022. From these non-duplicated donors, 83,234 donors who donated 400 mL whole blood or apheresis blood were selected as subjects for analysis, of whom 2132 (2.6%) had VVRs. The associations of sleep duration the night before donation and the timing of the last meal before donation with VVRs were analysed together with general risk factors for VVRs, such as age, sex, body weight, donation experience and blood collection type.

Results: Younger age, female gender, lower body weight, first-time donation and apheresis donor were clear risk factors for VVRs in univariate analysis, although female gender and first-time donation were not identified as independent risk factors in multivariate analysis. There was no dose-dependent relationship between sleep duration or fasting time and VVR incidence, nor was any association identified in multivariate analysis.

Conclusion: Neither sleep duration nor donor-reported fasting time had any association with VVRs under the routine practice of providing snacks and drinks to donors just before blood donation. The present findings should help blood collection agencies to appropriately assess the risk of VVRs based on donor-reported sleep and fasting times.

Background and objectives: Screening for transfusion-transmitted infections (TTIs) among blood donors is done using qualitative screening assays. Screening values that are close to cut-off values lie in the uncertainty zone, often denoted as the grey zone (GZ). This scoping review evaluated studies that have assessed the GZ reactivity by supplementary tests and its consequences.

Materials and methods: Studies evaluating GZ or indeterminate or inconclusive results for TTI screening among blood donors were searched using PubMed, Scopus and Google Scholar databases. Full text for the included articles was reviewed and analysed for study characteristics, TTI screening and GZ reactivity. This included GZ range, repeat or confirmatory testing, follow-up of such donors, effect on donor deferral and collected blood units.

Results: A total of 16 studies were included. GZ was evaluated for human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), syphilis, Chagas disease and human T-lymphotropic virus (HTLV). GZ values ranged from 0.5 to 1.2 times sample to cut-off (S/CO) values in different studies. The protocol for repeat/confirmatory testing was also heterogeneous. During repeat testing, many donors were found to be reactive or repeat GZ reactive. In confirmatory assays, the majority were negative, but many were positive or indeterminate. The protocol for donor follow-up and deferral protocols also varied significantly among different centres.

Conclusion: GZ evaluation showed a small yet significant risk of TTI from samples identified within the GZ range. There is further need for follow-up studies to establish TTI risk from repeat reactive or indeterminate samples, which will help in establishing uniform protocols for GZ samples.

Background and objectives: Unsuccessful red blood cell (RBC) transfusion, necessitating unscheduled repeat transfusion, is common and costly. Several technologies have been developed to assess stored blood quality, but the potential cost-effectiveness of pretransfusion testing versus no testing to prevent unscheduled re-transfusion is unknown.

Materials and methods: Projected benefits and costs of implementing a hypothetical pretransfusion assay were evaluated using Markov models with 10,000 Monte Carlo simulations. Chronic RBC transfusions were modelled at 1-month intervals over a 1-year time horizon, for 'simple' and 'complicated' (requiring antigen matching) cohorts. Model inputs included transfusion costs and quality-of-life weights. Cost-effectiveness was defined as incremental net monetary benefit (INMB) > 0, assuming willingness to pay <$50,000 per quality-adjusted life year (QALY).

Results: The Centers for Medicare and Medicaid Services reimbursement for a single-unit RBC transfusion was $970 ($853-$1313) and $2377 ($2057-$3317), respectively, for the simple and complicated cohorts. The hypothetical assay was priced at $100 ($38-$163) and was assumed to lower unscheduled re-transfusions by 30%, from 64% to 45% (40%-50%). Pretransfusion testing yielded 0.02 higher QALY (95% prediction interval [PI]: 0.01-0.02); annual per-patient cost savings of $269 (95% PI: $263-$276) and $3651 (95% PI: $3633-$3669), respectively, for the simple and complicated cohorts; and INMB of $1083 (95% PI: $985-$1180) and $4347 (95% PI: $4250-$4443).

Conclusion: Assessment of RBC quality by a hypothetical test prior to transfusion may reduce the incidence and associated costs of unscheduled re-transfusions and, with modelled assumptions, could be especially cost-effective for patients with complicated chronic transfusion requirements.