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International Journal of General... 2022Sickle cell disease (SCD) and thalassemia are common inherited blood disorders in Saudi Arabia, especially in Jazan Province. Patients with these disorders require...
PURPOSE
Sickle cell disease (SCD) and thalassemia are common inherited blood disorders in Saudi Arabia, especially in Jazan Province. Patients with these disorders require multiple blood transfusions, which may lead to alloimmunization because of mismatched blood group antigens. In this study, we examined the alloimmunization and autoimmunization rates in patients with SCD and thalassemia together with the involved antibodies.
PATIENTS AND METHODS
A cross-sectional study was conducted to review the transfusion history records of patients with SCD and thalassemia at Prince Mohammed bin Nasser Hospital, Jazan Province, Saudi Arabia.
RESULTS
Four-hundred thirty-eight patients (385 with SCD, 52 with β-thalassemia, and 1 with α-thalassemia) were received leukoreduced red cell transfusions. The alloimmunization and autoimmunization rates in patients with SCD were 12.98% and 0.52%, respectively. In patients with thalassemia, the alloimmunization and autoimmunization rates were 13.21% and 3.77%, respectively. The most prevalent antibodies in the study population were anti-E (17.19%) and anti-K (14.06%).
CONCLUSION
The alloimmunization and autoimmunization rates were determined in patients with SCD and thalassemia in Jazan Province, Saudi Arabia. The results highlight the need for extended phenotyping to include ABO, RH (D, C, c, E, e), K, Fy, Fy, Jk and Jk antigens in the screening panel. This will benefit patients to ensure better transfusion practices.
PubMed: 35450032
DOI: 10.2147/IJGM.S360320 -
Seminars in Thrombosis and Hemostasis Jun 2023Fetal and neonatal alloimmune thrombocytopenia (FNAIT) is a common cause of severe thrombocytopenia in newborns. Intracranial bleeding may lead to severe neurological... (Review)
Review
Fetal and neonatal alloimmune thrombocytopenia (FNAIT) is a common cause of severe thrombocytopenia in newborns. Intracranial bleeding may lead to severe neurological sequelae and mortality. Current management of pregnancies at risk is suboptimal. Prenatal FNAIT diagnosis commonly requires invasive procedures and therapy is associated with a high treatment burden. The present review explores advances in the field and their potential contribution to modification of the diagnostic and therapeutic landscape. Topics addressed include the role of noninvasive prenatal testing using fetal cell free DNA, insights into novel and prospective therapeutic options achieved through the development of murine models of FNAIT as well as the forecast for the progress in pregnancy risk stratification through advancement in the investigation of biological characteristics of alloantibodies and their association with the risk of fetal bleeding.
Topics: Pregnancy; Female; Infant, Newborn; Humans; Animals; Mice; Thrombocytopenia, Neonatal Alloimmune; Fetal Diseases; Prenatal Care; Prenatal Diagnosis; Hemorrhage; Antigens, Human Platelet
PubMed: 36368687
DOI: 10.1055/s-0042-1757900 -
The Veterinary Clinics of North... Jun 2024Alloimmune disorders occur in foals when pregnant mares produce antibodies against antigens on the foal's cells or tissues, and concentrate them within colostrum. Once... (Review)
Review
Alloimmune disorders occur in foals when pregnant mares produce antibodies against antigens on the foal's cells or tissues, and concentrate them within colostrum. Once foals nurse and absorb colostral antibodies, they can develop hematologic or cutaneous manifestations that can occur individually or in combination. These include neonatal isoerythrolysis, a hemolytic anemia directed against factors on the foal's erythrocytes, alloimmune thrombocytopenia when the antibodies are directed against platelet antigens, alloimmune neutropenia when they are directed against neutrophil antigens, and a combination of suspected alloimmune ulcerative dermatitis, neutropenia and thrombocytopenia. Foals can also develop neutrophilic dermatitis which is suspected to be alloimmune.
PubMed: 38852013
DOI: 10.1016/j.cveq.2024.05.001 -
Current Opinion in Organ Transplantation Dec 2019The microbiota in mammalian hosts can affect maturation and function of the immune system and has been associated with health and disease. We will review new findings on... (Review)
Review
PURPOSE OF REVIEW
The microbiota in mammalian hosts can affect maturation and function of the immune system and has been associated with health and disease. We will review new findings on how this dynamic environmental factor impacts alloimmunity and therapy in transplant hosts.
RECENT FINDINGS
The microbiota changes after transplantation and immunosuppressive therapy. New data indicate that different microbial community structures have distinct impact on graft outcome, from promoting, to inhibiting or being neutral to transplant survival. In addition, we will address reciprocal interactions between the microbiota and immunosuppressive drugs, as well as the suitability of the microbiota as a predictive biomarker and its utility as adjunct therapy in transplantation.
SUMMARY
Advances in microbiome sequencing and wider availability of gnotobiotic facilities are enabling mechanistic investigations into the commensal communities and pathways that modulate allograft outcome, responsiveness to immunosuppression and side effects of drugs. A better understanding of the functions of the microbiota may help mitigate drug toxicity, predict drug dosage and dampen alloimmunity in transplant patients.
Topics: Graft Survival; Humans; Microbiota; Organ Transplantation
PubMed: 31577594
DOI: 10.1097/MOT.0000000000000702 -
Journal of Medicine and Life Jul 2023The D antigen of the Rh blood group is considered clinically significant due to its ability to cause hemolytic transfusion reactions and hemolytic disease in the fetus... (Meta-Analysis)
Meta-Analysis Review
The D antigen of the Rh blood group is considered clinically significant due to its ability to cause hemolytic transfusion reactions and hemolytic disease in the fetus and newborn. This systematic review discusses the prevalence of RhD variants among pregnant women and the importance of including RhD genotyping for prenatal testing to detect RhD variants and prevent anti-D alloimmunization. A comprehensive literature search was conducted using scientific search engines, including PubMed and MEDLINE databases, with the keywords 'anti-D alloimmunization', 'RhD variant', and 'pregnant women.' The review adhered to the PRISMA guidelines. Meta-analysis was performed using MedCalc version 20. A significance level of p≤0.05 was considered statistically significant for all two-tailed tests. The meta-analysis included four articles that met the inclusion criteria. The total prevalence of RhD positivity (RhD+) was 61% (95% CI:34%-85%). The prevalence ranged from 22% to 82%, indicating a high degree of heterogeneity between studies (I2=98.71%, p<0.0001). The overall prevalence of D variants was 15% (95% CI, 9%-23%) with a prevalence of 0.05% to 100%, showing a high degree of heterogeneity between studies (I2=99.89%, p<0.0001). Anti-D alloimmunization could occur in pregnant women with some types of RhD variants. All four studies focused on molecular testing of samples showing inconsistent or weak results with at least two anti-D antibodies using serological methods.
Topics: Infant, Newborn; Pregnancy; Female; Humans; Pregnant Women; Fetus; Prevalence
PubMed: 37900088
DOI: 10.25122/jml-2023-0004 -
Hematology (Amsterdam, Netherlands) Dec 2023The use of blood products to resuscitate injured and massively bleeding patients in the prehospital and early in-hospital phase of the resuscitation is increasing. Using... (Review)
Review
The use of blood products to resuscitate injured and massively bleeding patients in the prehospital and early in-hospital phase of the resuscitation is increasing. Using group O red blood cells (RBC) and low titer group O whole blood (LTOWB) avoids an immediate hemolytic reaction from recipient's naturally occurring anti-A and - B, but choosing the RhD type for these products is more nuanced and requires the balancing of product availability and survival benefit against the risk of D-alloimmunization, especially in females of childbearing potential (FCP) due to the possible future occurrence of hemolytic disease of the fetus and newborn (HDFN). Recent models have estimated the risk of fetal/neonatal death from HDFN resulting from D-alloimmunization of an FCP during her trauma resuscitation at between 0-6.5% depending on her age at the time of the transfusion and other societal factors including trauma mortality, her age when she becomes pregnant, frequency of different genotypes in the population, and the probability that the woman will have children with different fathers; this is counterbalanced by an approximately 24% risk of death from hemorrhagic shock. This review will discuss the different models of HDFN outcomes following RhD-positive transfusion as well as the results of recent surveys where the public was asked about their preferences for urgent transfusion in light of the risks of fetal/neonatal adverse events.
Topics: Pregnancy; Female; Infant, Newborn; Child; Humans; Erythroblastosis, Fetal; Anemia, Hemolytic, Autoimmune; Erythrocytes; Blood Transfusion; Fetus
PubMed: 36607150
DOI: 10.1080/16078454.2022.2161215 -
Transfusion Medicine Reviews Jan 2021Red blood cell (RBC) transfusion to neonates is thought to rarely provoke an immune response. Neonatal testing guidelines suggest that antibody screening is not... (Review)
Review
Red blood cell (RBC) transfusion to neonates is thought to rarely provoke an immune response. Neonatal testing guidelines suggest that antibody screening is not necessary when the mother has no antibodies. Alternatively, maternal blood samples can be used for antibody screening and cross-matching. However, the guidelines are based on small-scale studies of white-dominant populations. Furthermore, transfusion-related alloimmunization is less well established among children and adolescents as a whole among Japanese and East Asians. To elucidate the incidence of transfusion-related alloimmunization among neonates, children, and adolescents, and whether current guidelines are applicable to Japanese populations, a nationwide retrospective multicenter cohort survey was conducted in 50 tertiary-care hospitals in Japan. Between 2001 and 2015 inclusive, recipients of at least 1 allogeneic RBC transfusion were categorized into groups A-F according to their age at the time of transfusion: (A) neonates <1 month; (B) infants 1 to <12 months; (C) children 1 to <5 years; (D) prepubescents 5 to <10 years; (E) young pubescents 10 to <15 years; and (F) adolescents/young adults 15 to <20 years. Excluding maternally derived antibodies and naturally occurring, cold-reactive, and/or nonspecific antibodies, 69 (0.61%) of 11350 RBC recipients <20 years old formed at least 1 clinically significant alloantibody. The alloimmunization rate differed significantly (P < .0001) by age: none (0%) of 3407 in group A; 11 (0.46%) of 2410 in group B; 18 (0.76%) of 2361 in group C; 9 (0.80%) of 1119 in group D; 12 (1.15%) of 1043 in group E; and 19 (1.88%) of 1010 in group F. Clearly different incidences of alloimmunization emerged in group A compared to B, C, D, E, or F, as confirmed by logistic regression analysis adjusted by numbers of donor exposure. Alloimmunization did not occur from RBC transfusions within the first month of life and rarely occurred (0.46%-0.80%) after transfusion within the first decade of life. Alloimmunization occurred in 1.15%-1.88% of young pubescents and adolescents/young adults. These findings support the use of guidelines developed in Europe and the United States for East Asian pediatric recipients.
Topics: Adolescent; Adult; Blood Transfusion; Child; Erythrocyte Transfusion; Erythrocytes; Humans; Isoantibodies; Japan; Multicenter Studies as Topic; Retrospective Studies; Young Adult
PubMed: 33012576
DOI: 10.1016/j.tmrv.2020.09.001 -
Haematologica Oct 2023Although red blood cell (RBC) transfusions save lives, some patients develop clinically-significant alloantibodies against donor blood group antigens, which then have...
Although red blood cell (RBC) transfusions save lives, some patients develop clinically-significant alloantibodies against donor blood group antigens, which then have adverse effects in multiple clinical settings. Few effective measures exist to prevent RBC alloimmunization and/or eliminate alloantibodies in sensitized patients. Donor-related factors may influence alloimmunization; thus, there is an unmet clinical need to identify which RBC units are immunogenic. Repeat volunteer blood donors and donors on iron supplements have elevated reticulocyte counts compared to healthy non-donors. Early reticulocytes retain mitochondria and other components, which may act as danger signals in immune responses. Herein, we tested whether reticulocytes in donor RBC units could enhance RBC alloimmunization. Using a murine model, we demonstrate that transfusing donor RBC units with increased reticulocyte frequencies dose-dependently increased RBC alloimmunization rates and alloantibody levels. Transfusing reticulocyte-rich RBC units was associated with increased RBC clearance from the circulation and a robust proinflammatory cytokine response. As compared to previously reported post-transfusion RBC consumption patterns, erythrophagocytosis from reticulocyte-rich units was increasingly performed by splenic B cells. These data suggest that reticulocytes in a donated RBC unit impact the quality of blood transfused, are targeted to a distinct compartment, and may be an underappreciated risk factor for RBC alloimmunization.
Topics: Humans; Mice; Animals; Reticulocytes; Isoantibodies; Blood Donors; Erythrocytes; Risk Factors
PubMed: 37078267
DOI: 10.3324/haematol.2023.282815 -
Asian Journal of Transfusion Science 2023In many fields of clinical medicine and blood transfusion, the human leukocyte antigen (HLA) system is crucial. Alloimmunization happens as a result of an immune... (Review)
Review
In many fields of clinical medicine and blood transfusion, the human leukocyte antigen (HLA) system is crucial. Alloimmunization happens as a result of an immune response to foreign antigens encountered during blood transfusion. This gives rise to alloantibodies against red blood cells (RBCs), HLA, or human platelet antigen (HPA). HLA alloimmunization following allogeneic transfusion was shown to be a result of contaminating white blood cells (WBCs) present in the product. It is a common complication of transfusion therapy that leads to difficulties in clinical intolerance and refractoriness to platelet transfusion during patient management. Single-donor platelets, prophylactic HLA matching, leukoreduction, and irradiation of cellular blood products are some of the mechanisms to prevent HLA alloimmunization during a blood transfusion. Now, the best approach to reduce the occurrence of primary HLA alloimmunization is the removal of WBCs from the blood by filtration.
PubMed: 38274979
DOI: 10.4103/ajts.ajts_144_21 -
World Journal of Gastroenterology Jul 2019The transplanted liver can modulate the recipient immune system to induce tolerance after transplantation. This phenomenon was observed nearly five decades ago.... (Review)
Review
The transplanted liver can modulate the recipient immune system to induce tolerance after transplantation. This phenomenon was observed nearly five decades ago. Subsequently, the liver's role in multivisceral transplantation was recognized, as it has a protective role in preventing rejection of simultaneously transplanted solid organs such as kidney and heart. The liver has a unique architecture and is home to many cells involved in immunity and inflammation. After transplantation, these cells migrate from the liver into the recipient. Early studies identified chimerism as an important mechanism by which the liver modulates the human immune system. Recent studies on human T-cell subtypes, cytokine expression, and gene expression in the allograft have expanded our knowledge on the potential mechanisms underlying immunomodulation. In this article, we discuss the privileged state of liver transplantation compared to other solid organ transplantation, the liver allograft's role in multivisceral transplantation, various cells in the liver involved in immune responses, and the potential mechanisms underlying immunomodulation of host alloresponses.
Topics: Allografts; Graft Rejection; Graft Survival; Humans; Immune Tolerance; Liver; Organ Transplantation; Transplantation, Homologous
PubMed: 31333306
DOI: 10.3748/wjg.v25.i25.3123