ABSTRACT
During 2018-2021, eight septic transfusion reactions occurred from transfusion of platelet units contaminated with Acinetobacter spp., Staphylococcus saprophyticus, Leclercia adecarboxylata, or a combination of those environmental organisms. Whether biofilm formation contributed to evasion of bacterial risk mitigations, including bacterial culture, point-of-care testing, or pathogen-reduction technology, is unclear. We designed a 12-well plate-based method to evaluate environmental determinants of single-species and multispecies biofilm formation in platelets. We evaluated bacteria isolated from septic transfusion reactions for biofilm formation by using crystal violet staining and enumeration of adherent bacteria. Most combinations of bacteria had enhanced biofilm production compared with single bacteria. Combinations involving L. adecarboxylata had increased crystal violet biofilm production and adherent bacteria. This study demonstrates that transfusion-relevant bacteria can produce biofilms well together. More work is needed to clarify the effect of biofilms on platelet bacterial risk control strategies, but US Food and Drug Administration-recommended strategies remain acceptable.
Subject(s)
Biofilms , Blood Platelets , Platelet Transfusion , Biofilms/growth & development , Humans , Platelet Transfusion/adverse effects , Blood Platelets/microbiology , Bacteria/isolation & purification , Transfusion ReactionABSTRACT
During coronary artery bypass grafting (CABG), the surgical procedure, particularly the manipulation of the major arteries of the heart, induces a significant inflammatory state that may compromise platelet function to the extent that platelet transfusion is required. Given stored platelets as a major source of biological mediators, this study investigates the effects of platelet transfusion on the major pro-aggregatory, pro-inflammatory and immunomodulatory markers of platelets. Platelets from 20 patients, 10 who received platelet transfusion and 10 without, were subjected to flow cytometery where P-selectin and CD40 ligand (CD40L) expressions and PAC-1 binding (activation-specific anti GPIIb/GPIIIa antibody) analysed at five-time points of 24 h before surgery, immediately, 2 h, 24 h and 1 week after surgery. Analysis of intra-platelet transforming growth factor-beta-1 (TGF-ß1) was also conducted using western blotting. Patients with platelet transfusion showed increased levels of P-selectin, CD40L and intra-platelet TGF-ß1 2-h after surgery compared to those without transfusion (p < 0.05). PAC-1 binding was increased 24 h after surgery in transfused patients (p < 0.05). Given the significant post-transfusion elevation of platelet TGF-ß1, P-sel/CD40L reduction in transfused patients a week after was of much interest. This study showed for the first time the significant effects of platelet transfusion on the pro-inflammatory, pro-aggeregatory and immunomodulatory state of platelets in CABG patients, which manifested with immediate, midterm and delayed consequences. While the increased pro-inflammatory conditions manifested as an immediate effect of platelet transfusion, the pro-aggregatory circumstances emerged 24 h post-transfusion. A week after surgery, attenuations of pro-inflammatory markers of platelets in transfused patients were shown, which might be due to the immunomodulatory effects of TGF-ß1.
Subject(s)
Blood Platelets , CD40 Ligand , Coronary Artery Bypass , P-Selectin , Platelet Transfusion , Humans , Coronary Artery Bypass/adverse effects , Blood Platelets/metabolism , Male , Female , P-Selectin/blood , P-Selectin/metabolism , Middle Aged , CD40 Ligand/blood , CD40 Ligand/metabolism , Aged , Transforming Growth Factor beta1/blood , Transforming Growth Factor beta1/metabolism , Inflammation/blood , Platelet AggregationABSTRACT
Introduction: CD39 plays an important role in the immunoregulation and inhibition of effector cells. It is expressed on immune cells, including Tregs, and on extracellular vesicles (EVs) budding from the plasma membrane. Platelet transfusion may induce alloimmunization against HLA-I antigens, leading to refractoriness to platelet transfusion with severe consequences for patients. Tregs may play a key role in determining whether alloimmunization occurs in patients with hematologic disorders. We hypothesized that CD39+ EVs might play an immunoregulatory role, particularly in the context of platelet transfusions in patients with hematologic disorders. Such alloimmunization leads to the production of alloantibodies and is sensitive to the regulatory action of CD39. Methods: We characterized CD39+ EVs in platelet concentrates by flow cytometry. The absolute numbers and cellular origins of CD39+ EVs were evaluated. We also performed functional tests to evaluate interactions with immune cells and their functions. Results: We found that CD39+ EVs from platelet concentrates had an inhibitory phenotype that could be transferred to the immune cells with which they interacted: CD4+ and CD8+ T lymphocytes (TLs), dendritic cells, monocytes, and B lymphocytes (BLs). Moreover, the concentration of CD39+ EVs in platelet concentrates varied and was very high in 10% of concentrates. The number of these EVs present was determinant for EV-cell interactions. Finally, functional interactions were observed with BLs, CD4+ TLs and CD39+ EVs for immunoglobulin production and lymphoproliferation, with potential implications for the immunological management of patients.
Subject(s)
Blood Platelets , Extracellular Vesicles , Tetraspanin 29 , Humans , Extracellular Vesicles/immunology , Extracellular Vesicles/metabolism , Blood Platelets/immunology , Blood Platelets/metabolism , Tetraspanin 29/metabolism , Cell Communication/immunology , Platelet Transfusion , Female , B-Lymphocytes/immunology , B-Lymphocytes/metabolism , Male , Apyrase/metabolism , Apyrase/immunology , T-Lymphocytes, Regulatory/immunology , T-Lymphocytes, Regulatory/metabolism , Antigens, CDABSTRACT
Platelet transfusions are routine procedures in clinical treatment aimed at preventing bleeding in critically ill patients, including those with cancer, undergoing surgery, or experiencing trauma. However, platelets are susceptible blood cells that require specific storage conditions. The availability of platelet concentrates is limited to five days due to various factors, including the risk of bacterial contamination and the occurrence of physical and functional changes known as platelet storage lesions. In this article, the problems related to platelet storage lesions are categorized into four groups depending on research areas: storage conditions, additive solutions, new testing methods for platelets (proteomic and metabolomic analysis), and extensive data modeling of platelet production (mathematical modeling, statistical analysis, and artificial intelligence). This article provides extensive information on the challenges, potential improvements, and novel perspectives regarding platelet storage.
Subject(s)
Blood Platelets , Blood Preservation , Platelet Transfusion , Humans , Blood Platelets/metabolism , Blood Preservation/methods , Platelet Transfusion/methods , Proteomics/methods , Metabolomics/methodsABSTRACT
BACKGROUND: Cesarean delivery (CD) is one of the most common surgeries performed worldwide, with increasing yearly rates. Although neuraxial techniques remain the preferred anesthesia method for CD, maternal thrombocytopenia remains a prominent contraindication. Formation of spinal\epidural hematomas are extremely rare, however the minimal thrombocyte count required for safe neuraxial anesthesia is still under debate. Although transfusion of thrombocytes for the purpose of neuraxial anesthesia is still not recommended, patients with severe thrombocytopenia (less than 50 × 103/uL) are given thrombocyte transfusion for surgical hemostasis. OBJECTIVES: To evaluate the anesthetic approach to caesarean deliveries in parturients with severe thrombocytopenia who received thrombocyte transfusion aimed for improved surgical hemostasis. METHODS: We conducted a single center, retrospective cohort study. Results: A total of five cases were found, four of which were given spinal anesthesia immediately following thrombocyte transfusion. One patient was denied spinal anesthesia because her thrombocyte count following transfusion failed to reach safe levels. None of our cases had anesthesia-related complications recorded. CONCLUSIONS: We examined the anesthetic management parturients with severe thrombocytopenia who needed cesarean delivery and were transfused with thrombocytes for surgical hemostasis. In such cases, spinal anesthesia may be considered due to the serious risks associated with general anesthesia.
Subject(s)
Anesthesia, Obstetrical , Anesthesia, Spinal , Cesarean Section , Platelet Transfusion , Pregnancy Complications, Hematologic , Thrombocytopenia , Humans , Female , Cesarean Section/methods , Cesarean Section/adverse effects , Pregnancy , Thrombocytopenia/therapy , Thrombocytopenia/etiology , Retrospective Studies , Platelet Transfusion/methods , Adult , Anesthesia, Obstetrical/methods , Anesthesia, Spinal/methods , Pregnancy Complications, Hematologic/therapy , Anesthesia, Epidural/methods , Hemostasis, Surgical/methodsABSTRACT
BACKGROUND: Damage-control resuscitation has come full circle, with the use of whole blood and balanced components. Lack of platelet availability may limit effective damage-control resuscitation. Platelets are typically stored and transfused at room temperature and have a short shelf-life, while cold-stored platelets (CSPs) have the advantage of a longer shelf-life. The US military introduced CSPs into the battlefield surgical environment in 2016. This study is a safety analysis for the use of CSPs in battlefield trauma. METHODS: The Department of Defense Trauma Registry and Armed Services Blood Program databases were queried to identify casualties who received room-temperature-stored platelets (RSPs) or both RSPs and CSPs between January 1, 2016, and February 29, 2020. Characteristics of recipients of RSPs and RSPs-CSPs were compared and analyzed. RESULTS: A total of 274 patients were identified; 131 (47.8%) received RSPs and 143 (52.2%) received RSPs-CSPs. The casualties were mostly male (97.1%), similar in age (31.7 years), with a median Injury Severity Score of 22. There was no difference in survival for recipients of RSPs (88.5%) versus RSPs-CSPs (86.7%; p = 0.645). Adverse events were similar between the two cohorts. Blood products received were higher in the RSPs-CSPs cohort compared with the RSPs cohort. The RSPs-CSPs cohort had more massive transfusion (53.5% vs. 33.5%, p = 0.001). A logistic regression model demonstrated that use of RSPs-CSPs was not associated with mortality, with an adjusted odds ratio of 0.96 (p > 0.9; 95% confidence interval, 0.41-2.25). CONCLUSION: In this safety analysis of RSPs-CSPs compared with RSPs in a combat setting, survival was similar between the two groups. Given the safety and logistical feasibility, the results support continued use of CSPs in military environments and further research into how to optimize resuscitation strategies. LEVEL OF EVIDENCE: Therapeutic/Care Management; Level IV.
Subject(s)
Blood Preservation , Feasibility Studies , Platelet Transfusion , Humans , Male , Female , Adult , Blood Preservation/methods , Platelet Transfusion/methods , Platelet Transfusion/statistics & numerical data , United States/epidemiology , Injury Severity Score , Registries , Resuscitation/methods , Cold Temperature , Retrospective Studies , Wounds and Injuries/therapy , Wounds and Injuries/mortality , Military Personnel/statistics & numerical data , War-Related Injuries/therapy , War-Related Injuries/mortality , Military Medicine/methods , Blood PlateletsABSTRACT
Introduction: Platelet concentrates are blood products obtained from donor's blood, and their conservation must be subject to a strict quality control process to guarantee a safe and high-performance product in treating diseases that require their use. Methods: We designed a cross-sectional study to determine the total compliance rate in platelet concentrates obtained in the blood bank of the Cayetano Heredia Hospital in Lima during November and December of 2019. The Buffy method Coat obtained the platelet concentrates, and parameters such as platelet count and residual leukocytes, pH, and swirling effect were evaluated according to the National Hemotherapy and Blood Bank Program criteria. Results: The platelet count had a mean of 6.66 ± 3.94 x 10¹°/µL, the platelet concentrates had a mean of 56.30 ± 6.22 mL, and all, without exception, had the presence of the Swirling phenomenon. The pH had a mean of 7.64 ± 0.15, while the leukocyte count had a mean of 4.22 ± 3.51 x 107/µL. Regarding compliance by the parameters evaluated, it was evident that the platelet and leukocyte count had moderate compliance rates of 43.6% and 24.1%, while the pH and swirling effect had rates of 100% in both cases. The total compliance rate was 54.9% (95% confidence interval: 46.0 to 63.5). Conclusions: The compliance rate of platelet concentrates is moderate, and it is necessary to implement a process of continuous quality improvement in the blood bank.
Introducción: Los concentrados plaquetarios son hemoderivados obtenidos de la sangre, y su conservación debe estar supeditada a un estricto proceso de control de calidad para garantizar un producto inocuo y de alto rendimiento en el tratamiento de enfermedades que requieran su uso. Métodos: Diseñamos un estudio transversal que tuvo por objetivo determinar la tasa de conformidad total en concentrados plaquetarios obtenidos en el banco de sangre del Hospital Cayetano Heredia de Lima durante los meses de noviembre y diciembre del año 2019. Los concentrados plaquetarios fueron obtenidos por el método de Buffy Coat y se evaluaron parámetros como el recuento de plaquetas y leucocitos residuales, pH y efecto swirling, según criterios del Programa Nacional de Hemoterapia y Bancos de Sangre. Resultados: El recuento de plaquetas tuvo una media de 6.66 ± 3.94 x1010/µL y los concentrados plaquetarios tuvieron una media de 56.30 ± 6.22 mL, y todos sin excepción tuvieron presencia de fenómeno Swirling. El pH tuvo una media de 7.64 ± 0.15, mientras que el recuento de leucocitos tuvo una media de 4.22 ± 3.51 x107/µL. En cuanto al cumplimiento por parámetro evaluado, se evidenció que el recuento de plaquetas y leucocitos tuvieron tasas de conformidad de 43.6% y 24.1%, mientras que el pH y efecto swirling tuvieron tasas del 100% en ambos casos. La tasa de conformidad total fue 54.9% (CI95%: 46.0 a 63.5). Conclusiones: La tasa de conformidad de los concentrados plaquetarios es moderada, y se requiere implementar un proceso de mejora continua de la calidad en el banco de sangre.
Subject(s)
Blood Banks , Blood Platelets , Quality Control , Humans , Peru , Cross-Sectional Studies , Platelet Count , Blood Banks/standards , Leukocyte Count , Hospitals , Hydrogen-Ion Concentration , Platelet Transfusion/standards , Platelet Transfusion/methodsABSTRACT
BACKGROUND: Platelet transfusions are frequently used in the intensive care unit (ICU), but current practices including used product types, volumes, doses and effects are unknown. STUDY DESIGN AND METHODS: Sub-study of the inception cohort study 'Thrombocytopenia and Platelet Transfusions in the ICU (PLOT-ICU)', including acutely admitted, adult ICU patients with thrombocytopenia (platelet count <150 × 109/L). The primary outcome was the number of patients receiving platelet transfusion in ICU by product type. Secondary outcomes included platelet transfusion details, platelet increments, bleeding, other transfusions and mortality. RESULTS: Amongst 504 patients with thrombocytopenia from 43 hospitals in 10 countries in Europe and the United States, 20.8% received 565 platelet transfusions; 61.0% received pooled products, 21.9% received apheresis products and 17.1% received both with a median of 2 (interquartile range 1-4) days from admission to first transfusion. The median volume per transfusion was 253 mL (180-308 mL) and pooled products accounted for 59.1% of transfusions, however, this varied across countries. Most centres (73.8%) used fixed dosing (medians ranging from 2.0 to 3.5 × 1011 platelets/transfusion) whilst some (mainly in France) used weight-based dosing (ranging from 0.5 to 0.7 × 1011 platelets per 10 kg body weight). The median platelet count increment for a single prophylactic platelet transfusion was 2 (-1 to 8) × 109/L. Outcomes of patients with thrombocytopenia who did and did not receive platelet transfusions varied. CONCLUSIONS: Among acutely admitted, adult ICU patients with thrombocytopenia, 20.8% received platelet transfusions in ICU of whom most received pooled products, but considerable variation was observed in product type, volumes and doses across countries. Prophylactic platelet transfusions were associated with limited increases in platelet counts.
Subject(s)
Intensive Care Units , Platelet Transfusion , Thrombocytopenia , Humans , Platelet Transfusion/statistics & numerical data , Thrombocytopenia/therapy , Female , Male , Cohort Studies , Middle Aged , Aged , Europe , Adult , Critical Care/methodsABSTRACT
BACKGROUND: Immature platelets, young and large platelets recently released from the bone marrow, have gained interest over the last decade as a clinically informative variable during thrombocytopenic presentations. These immature platelets are found in all donated platelet units, however, the role, if any, that these younger platelets play post transfusion is not known. It has also been reported that the immune response can affect responses to platelet transfusions. Thus, we looked at PLT increments in a cohort of neonates receiving platelet transfusions in our neonatal intensive care unit. METHODS: During a twelve-month period, platelet transfusions received by neonates born and not discharged from our institution at time of transfusion were retrospectively analyzed. In the study period a total of 33 patients received either a single or multiple transfusions during their hospitalization, for a total of 100 transfusion events. RESULTS: The cohort was mostly premature neonates with a mean gestational age of 29.6 weeks. The units transfused appeared to have a broad range of absolute immature platelet counts (A-IPC) but overall, it was similar between those receiving single or multiple transfusions. Considering that platelet count was similar among aliquots transfused, it appeared that count increments were influenced by higher A-IPC content of the aliquot especially among 2nd trimester and 3rd trimester premature neonates. Patients with higher baseline platelet count (PLT) tended to receive a single transfusion aliquot while those receiving multiple transfusions had lower baseline PLT (p = 0.0022). Looking at aliquot dose, regardless if receiving a single or multiple transfusions, younger patients received incrementally higher dose (ml/kg) with each transfusion. CONCLUSIONS: A-IPC in platelet aliquots transfused to neonates may influence post-transfusion PLT. Full effect of A-IPC in platelet aliquots may not be seen since irradiation of units may hamper immature platelets viability and function. Further research is needed to determine if A-IPC plays an active role to limit the need for further transfusions of patients receiving transfusions.
Subject(s)
Platelet Transfusion , Humans , Infant, Newborn , Platelet Count , Retrospective Studies , Female , Male , Blood PlateletsABSTRACT
BACKGROUND: Cutibacterium acnes, a common anaerobic platelet concentrate (PC) contaminant, has been associated with rare mild adverse transfusion reactions and is often considered a harmless commensal. Notably, C. acnes can cause chronic infections and has been shown to induce the release of proinflammatory cytokines by immune cells. Since elevated concentrations of proinflammatory factors in PCs have been linked to noninfectious adverse reactions, this study aimed to assess whether C. acnes could elicit the release and accumulation of proinflammatory factors during PC storage, thereby enhancing the risk of such reactions. STUDY DESIGN/METHODS: Four ABO-matched buffy coat PCs were pooled and split into six units, each were inoculated with either saline (negative control), a Staphylococcus aureus isolate (positive control, 30 colony forming units [CFU]/unit), or four C. acnes PC isolates (10 CFU/mL) and stored at 20-24°C with agitation. Bacterial counts, platelet activation, and concentration of proinflammatory factors were assessed on days 0, 3, and 5. N = 3. RESULTS: C. acnes counts remained stable, while S. aureus proliferated reaching 108CFU/mL by the end of PC storage. By day 5, no significant differences in platelet activation or proinflammatory cytokine profiles were observed in C. acnes-contaminated PCs compared to the negative control (p > .05), while there was a significant increase (p ≤ .05) in sCD40L concentration (day 3), and platelet activation and IL-8 concentration (day 5) in S. aureus-contaminated units. DISCUSSION: C. acnes contamination does not promote the accumulation of proinflammatory factors in the absence of proliferation during storage and may not enhance the risk of inflammatory reactions when transfused to patients.
Subject(s)
Blood Platelets , Blood Preservation , Staphylococcus aureus , Humans , Blood Platelets/microbiology , Propionibacteriaceae , Cytokines/blood , Cytokines/metabolism , Platelet Activation , Platelet Transfusion/adverse effects , Inflammation/microbiologyABSTRACT
BACKGROUND AND OBJECTIVES: Platelets for transfusion are evaluated for in vivo quality using recovery and survival measurements in healthy human subjects. Radiolabelling is the standard for tracing platelets post-transfusion but imposes logistical and technical limitations. This study investigates the in vitro feasibility of labelling platelets with the calcein family of fluorescent dyes as an alternative to radioisotopes or biotin. MATERIALS AND METHODS: Protocols for radiolabelling were adapted for use with calcein acetoxymethyl ester (CAM) and biotin. Labelled platelets were analysed by flow cytometry and evaluated for activation and function. We tested feasibility for labelling without manipulation of platelets and for multiplexing of samples. RESULTS: Labelling at 2 µg CAM/1010 platelets resulted in >99% of CAM+ platelets. There was no significant difference in activation or aggregation between CAM-labelled or biotinylated platelets and vehicle controls although %CD62P+ was significantly lower in platelets that were not processed for labelling. Addition of CAM to the platelet storage bag labelled >95% of platelets. Platelet populations labelled with different dyes could be distinguished by flow cytometry. CONCLUSION: These data provide a rationale for further development of CAM and other fluorescent dyes as tools for measuring post-transfusion kinetics of platelets.
Subject(s)
Blood Platelets , Flow Cytometry , Fluoresceins , Fluorescent Dyes , Humans , Blood Platelets/cytology , Blood Platelets/metabolism , Flow Cytometry/methods , Staining and Labeling/methods , Platelet Transfusion/methods , Cell Survival , Male , FemaleABSTRACT
OBJECTIVE: To determine the feasibility, efficacy, and safety of early cold stored platelet transfusion compared with standard care resuscitation in patients with hemorrhagic shock. BACKGROUND: Data demonstrating the safety and efficacy of early cold stored platelet transfusion are lacking following severe injury. METHODS: A phase 2, multicenter, randomized, open label, clinical trial was performed at 5 US trauma centers. Injured patients at risk of large volume blood transfusion and the need for hemorrhage control procedures were enrolled and randomized. The intervention was the early transfusion of a single apheresis cold stored platelet unit, stored for up to 14 days versus standard care resuscitation. The primary outcome was feasibility and the principal clinical outcome for efficacy and safety was 24-hour mortality. RESULTS: Mortality at 24 hours was 5.9% in patients who were randomized to early cold stored platelet transfusion compared with 10.2% in the standard care arm (difference, -4.3%; 95% CI, -12.8% to 3.5%; P =0.26). No significant differences were found for any of the prespecified ancillary outcomes. Rates of arterial and/or venous thromboembolism and adverse events did not differ across treatment groups. CONCLUSIONS AND RELEVANCE: In severely injured patients, early cold stored platelet transfusion is feasible, safe and did not result in a significant lower rate of 24-hour mortality. Early cold stored platelet transfusion did not result in a higher incidence of arterial and/or venous thrombotic complications or adverse events. The storage age of the cold stored platelet product was not associated with significant outcome differences. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT04667468.
Subject(s)
Blood Preservation , Platelet Transfusion , Shock, Hemorrhagic , Humans , Male , Female , Adult , Middle Aged , Shock, Hemorrhagic/therapy , Shock, Hemorrhagic/etiology , Blood Preservation/methods , Feasibility Studies , Wounds and Injuries/therapy , Wounds and Injuries/complications , Treatment Outcome , Resuscitation/methods , Cold TemperatureABSTRACT
BACKGROUND: Platelet inventory constraints necessitate ABO-incompatible platelet transfusion. Many minimize the hemolytic impact by confirming low titre (LT) donor isohemagglutinins. This process is costly. Pathogen-reduced platelets (PRP) in platelet additive solutions (PAS) will dilute plasma and decrease high-titre isohemagglutinins (HT). We determined the proportion of HT platelets and incompatible transfusions for units suspended in plasma to reassess the need for titres following introduction of PRP/PAS. STUDY DESIGN AND METHODS: Our titre method is manual tube (1:50) dilution of platelet supernatant from apheresis or whole blood derived buffy coat pools suspended in plasma, tested with A1/B red cells. Testing included 49,058 pooled and 11,738 apheresis platelets over 4 years. The HT proportion, rate of out-of-group transfusions, and hemolytic reactions were determined. The impact of PAS dilution was estimated. RESULTS: Totally 60,796 platelet units were tested. Group O pooled and group B apheresis platelets had HT in 6.6% and 5.7%, respectively. Group A pooled and apheresis platelets included 2% with HT. Approximately 25% of platelets transfused were ABO-incompatible and no hemolytic reactions were reported. Based on the proportions of PAS-E and plasma for PRP platelets, plasma from each donor comprises 11 mL (6% of total volume) vs 20-257 mL in untreated pools. PAS-E will replace and dilute residual plasma by at least 50%. DISCUSSION: Rare platelet pools may demonstrate HT. PRP platelets with PAS will reduce titres and may abrogate the need for titration. A strategy of group specific transfusion or transfusion of group A PRP platelet transfusions may be a safe alternative.
Subject(s)
ABO Blood-Group System , Blood Platelets , Platelet Transfusion , Plateletpheresis , Humans , Platelet Transfusion/methods , Blood Platelets/cytology , Plateletpheresis/methods , Blood Group Incompatibility , HemagglutininsABSTRACT
BACKGROUND: Fetal and Neonatal Alloimmune Thrombocytopenia (FNAIT) results from maternal platelet alloimmunization against paternal antigens inherited by the fetus, most often due to the Human Platelet Antigen (HPA)-1 system in Caucasians. We investigated in 2023, a 30-year-old Caucasian woman Gravida 2 Para 1 who gave birth at 35 weeks of gestation to a male (body weight 2210 g) without signs of bleeding. A severe thrombocytopenia (platelet count at 3 G/L) was discovered incidentally a few hours after delivery in the context of the management of a respiratory distress. The newborn recovered after one platelet concentrate transfusion and normalized his platelet count at Day 5. STUDY DESIGN AND METHODS: FNAIT investigation was performed according to guideline recommendations. Platelet genotyping was carried out by multiplex PCR. Maternal serological investigation included Monoclonal Antibody-specific Immobilization of Platelet Antigens method (MAIPA) and Luminex technology. RESULTS: Parental and newborn genotyping pointed out an HPA-4 incompatibility between the mother and the newborn and the father. Serological investigation revealed an anti-HPA-4b alloantibody confirming the diagnosis of neonatal alloimmune thrombocytopenia. CONCLUSION: We described the third case of anti-HPA-4b alloantibody discovered in a Caucasian mother. This case strengthens the need for reference laboratory to genotype a panel of HPA alleles reflecting local genetic population diversity and for crossmatch of maternal serum with fresh paternal platelets in clinical suspected cases of neonatal alloimmune thrombocytopenia.
Subject(s)
Antigens, Human Platelet , Isoantibodies , Thrombocytopenia, Neonatal Alloimmune , Humans , Isoantibodies/blood , Isoantibodies/immunology , Thrombocytopenia, Neonatal Alloimmune/immunology , Thrombocytopenia, Neonatal Alloimmune/blood , Female , Antigens, Human Platelet/immunology , Antigens, Human Platelet/genetics , Infant, Newborn , Adult , Pregnancy , Male , Platelet Transfusion , White PeopleABSTRACT
BACKGROUND: Platelet radiolabeling with radioisotopes is currently used for human platelet recovery and survival studies. Biotinylation enables ex vivo post-transfusion platelet function testing. Whether platelet biotinylation itself affects platelet function is controversial. STUDY DESIGN AND METHODS: Platelet concentrates from healthy humans were stored for 6 days. Samples were obtained at 1 or 2 and 6 days, and platelets were labeled following a radiolabeling protocol using saline instead of radioactive indium-111 (sham radiolabeling [sham-RL]). Alternatively, a newly developed biotinylation protocol, a washing protocol, or an unmanipulated control sample were used. Platelet function was assessed by flow cytometry after stimulation with platelet agonists and labeling of platelets with platelet activation markers. To test whether platelets can be activated after transfusion, labeled platelets were transfused into nonobese diabetic/severe combined immunodeficiency mice, and samples were obtained 1 h after transfusion. RESULTS: The activation profile of biotinylated platelets was comparable to sham-RL platelets before transfusion except for significantly less α-degranulation and more phosphatidyl serine exposure on storage day 1/2. There was no significant difference between sham-RL and biotinylated platelets on storage day 6. Sham-RL and biotinylated platelets were significantly less activatable than washed and unmanipulated control platelets. After transfusion, the activation profile of biotinylated platelets was largely indistinguishable from unmanipulated ones. DISCUSSION: The decrease in activation level in biotinylated platelets we and others observed appears mainly due to the physical manipulation during the labeling process. In conclusion, biotinylated platelets allow for post-transfusion function assessment, a major advantage over radiolabeling.
Subject(s)
Biotinylation , Blood Platelets , Blood Preservation , Mice, SCID , Platelet Transfusion , Humans , Blood Platelets/metabolism , Animals , Mice , Blood Preservation/methods , Mice, Inbred NOD , Platelet Activation , Biotin/metabolism , Biotin/chemistry , Platelet Function Tests/methodsABSTRACT
Wound dehiscence is a common complication after secondary alveolar bone grafting (SABG), leading to unfavourable surgical outcomes. Studies have shown that autologous platelet concentrates (APC) may enhance wound healing and improve outcomes. Therefore, this review aimed to evaluate in patients with alveolar clefts, whether using APC and iliac crest bone graft can mitigate the likelihood of wound dehiscence formation compared with those who underwent iliac bone grafting only following SABG. A comprehensive literature search was conducted using various electronic databases, including PubMed, Embase, Scopus, Web of Science, EBSCOhost, Ovid MEDLINE, LILACS, Cochrane Library, and grey literature, to include studies until July 31, 2023, without any restriction to language and time of publication. Only randomized (RCT) and controlled (CCT) clinical trials were included. Two independent reviewers screened the studies based on the predefined criteria, after which a qualitative and quantitative analysis was conducted. The search yielded 821 studies, of which seven were deemed eligible for systematic review. The risk of bias assessment done using "The Cochrane collaboration tool for risk of bias assessment" for six RCTs and the "Risk of Bias in Non-randomized Studies - of Interventions" for one CCT revealed a moderate to high risk of bias. The meta-analysis of five studies showed that the overall risk of developing wound dehiscence was lower in the APC group (RR = 0.33; 95% CI: 0.16, 0.71; p = 0.005; χ2 = 0.82; I2 = 0%). Subgroup analyses based on study design further supported these findings. Although the adjuvant use of APC for alveolar cleft reconstruction reduces the risk of wound dehiscence, more studies with increased scientific rigour and fewer confounding variables are warranted.
Subject(s)
Alveolar Bone Grafting , Surgical Wound Dehiscence , Humans , Surgical Wound Dehiscence/etiology , Surgical Wound Dehiscence/prevention & control , Alveolar Bone Grafting/methods , Ilium/transplantation , Cleft Palate/surgery , Platelet Transfusion , Bone Transplantation/methodsABSTRACT
PURPOSE: Prophylactic platelet transfusions (PT) aim to reduce bleeding. We assessed whether restrictive PT compared to prophylactic strategy could apply in ICU. MATERIAL AND METHODS: We conducted a retrospective monocentric study including patients >18 yo with haematological malignancy admitted to the ICU with thrombocytopenia <20 G/L between 2018 and 2021. Patients were classified in 2 groups according transfusion strategy applied during the first 3 days: prophylactic or restrictive transfusion. RESULTS: 180 patients were included, 87 and 93 in the restrictive and prophylactic groups respectively. After propensity-score analysis, 2 groups of 54 matched patients were analyzed. Restrictive strategy led to a significant reduction in PT with incidence rate for 100-ICU-patients-days of 34.9 and 49.9, incidence rate ratio = 0.699 [0.5-0.9], p = 0.006, representing a 31% decrease. Decreased PT persisted until day 28 with platelet concentrates transfusions-free days at day 28 of 21 [13-25] and 16.5 [10.2-21] in the 2 groups (p = 0.04). Restrictive strategy did not result in higher grade ≥ 2 bleeding. Transfusion efficiency was low with similar number of days with platelet <10 or < 20 G/L regardless of strategy. Platelet transfusion strategy was not associated with 28-day mortality. Platelet nadir <5G/L was associated with day-28 mortality with HR = 1.882 [1.011-3.055], p = 0.046. CONCLUSION: A restrictive PT strategy appears feasible in the ICU.