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Journal of Clinical Medicine May 2022Hemolytic disease of the fetus and newborn (HDFN), as well as fetal and neonatal alloimmune thrombocytopenia (FNAIT), represent two important disease entities that are... (Review)
Review
Hemolytic disease of the fetus and newborn (HDFN), as well as fetal and neonatal alloimmune thrombocytopenia (FNAIT), represent two important disease entities that are caused by maternal IgG antibodies directed against nonmaternally inherited antigens on the fetal blood cells. These antibodies are most frequently directed against the RhD antigen on red blood cells (RBCs) or the human platelet antigen 1a (HPA-1a) on platelets. For optimal management of pregnancies where HDFN or FNAIT is suspected, it is essential to determine the RhD or the HPA-1a type of the fetus. Noninvasive fetal RhD typing is also relevant for identifying which RhD-negative pregnant women should receive antenatal RhD prophylaxis. In this review, we will give an overview of the clinical indications and technical challenges related to the noninvasive analysis of fetal RBCs or platelet types. In addition, we will discuss the ethical implications associated with the routine administration of antenatal RhD to all pregnant RhD-negative women and likewise the ethical challenges related to making clinical decisions concerning the mother that have been based on samples collected from the (presumptive) father, which is a common practice when determining the risk of FNAIT.
PubMed: 35629001
DOI: 10.3390/jcm11102877 -
The Journal of Maternal-fetal &... Dec 2022Despite the availability guidelines to prevent RhD alloimmunization, severe hemolytic disease of fetus and newborn still occurs in high-income countries. The aim of the...
INTRODUCTION
Despite the availability guidelines to prevent RhD alloimmunization, severe hemolytic disease of fetus and newborn still occurs in high-income countries. The aim of the study was (1) To assess variations in practices for the prevention of RhD alloimmunization, and (2) to understand midwives' acceptance and appropriation of fetal RhD genotyping.
METHODS
Descriptive cross-sectional survey of French midwives from September 2017 through January 2018. Participants were asked to complete an internet-based questionnaire that included three clinical vignettes. They were questioned about their practices concerning early pregnancy visit by RhD-negative women, prevention of RhD alloimmunization in women with second-trimester metrorrhagia, and RhD fetal genotyping.
RESULTS
A total of 827 midwives completed the questionnaire. Only 21.1% reported that they practice all the preventive measures recommended in early pregnancy. In a situation at high risk of RhD alloimmunization during pregnancy, 97.2% of midwives would perform immunoprophylaxis. Nearly, all midwives reported providing information about RhD alloimmunization (92.4%) at the beginning of pregnancy, although only 11.3% offered both written and verbal information; at the time of systematic anti-D immunoprophylaxis (28 weeks), 78% provided information, but only 2.7% both verbally and in writing. Finally, only 50.8% of midwives preferred to include RhD fetal genotyping in routine prenatal prophylaxis.
DISCUSSION
This study showed significant variations in French midwives' practices to prevent RhD alloimmunization. Better dissemination of guidelines is needed to improve both consistent use of these practices and the quality of information delivered to RhD-negative pregnant women.
Topics: Infant, Newborn; Female; Pregnancy; Humans; Rh Isoimmunization; Midwifery; Cross-Sectional Studies; Rho(D) Immune Globulin; Fetus; Surveys and Questionnaires; Rh-Hr Blood-Group System; Prenatal Diagnosis
PubMed: 34433367
DOI: 10.1080/14767058.2021.1957822 -
Characterization of pediatric transfusion-dependent thalassemia patients in a large academic center.Journal of Clinical Laboratory Analysis Sep 2023Transfusion-dependent thalassemia patients are at high risk of transfusion-related complications. Yet, there is scanty data on the frequency of transfusion reactions,...
BACKGROUND
Transfusion-dependent thalassemia patients are at high risk of transfusion-related complications. Yet, there is scanty data on the frequency of transfusion reactions, particularity alloimmunization among pediatric transfusion-dependent thalassemia patients. In addition, there is no consensus on the prophylactic antigen matching for prevention of alloimmunization or the extent of antigen matching for alloimmunized thalassemia patients.
METHODS
We conducted a retrospective study to assess the frequency and specificity of alloimmunization among pediatric transfusion-dependent thalassemia patients receiving ABO, RhD, and K-matched red blood cell units. In addition, we studied the association between patients' characteristics and alloimmunization. The clinical and transfusion records of transfusion-dependent thalassemia patients followed up at our institution between July 2018 and June 2022 were reviewed.
RESULTS
Ninety-two transfusion-dependent thalassemia patients having mean age of 13.37 years (SD, 5.56) were included in our study. Eight patients (9%) had developed clinically significant alloantibodies; six patients (6%) developed alloantibody against E antigen while two patients (2%) developed more than one alloantibody. Of alloimmunized patients, five patients had received transfusion outside Canada. Patients' sex, age, having a genotype variant, total number, and duration of transfusion received were not associated with the risk of alloimmunization. The transfusion-recipient's diagnosis of β-thalassemia, having developed autoantibody, and history of receiving transfusion outside Canada were associated with alloimmunization.
CONCLUSION
Blood matching for ABO, RhD, and K antigens resulted in, although not eliminated, lower frequency of alloimmunization than that previously reported among pediatric thalassemia patients. Extending matching to include Rh antigens could further reduce the rate of alloimmunization.
Topics: Humans; Child; Adolescent; Retrospective Studies; Thalassemia; Erythrocytes; beta-Thalassemia; Blood Transfusion; Transfusion Reaction; Blood Group Antigens; Isoantibodies; Anemia, Hemolytic, Autoimmune
PubMed: 37665129
DOI: 10.1002/jcla.24962 -
Ceska Gynekologie 2020Review article. (Review)
Review
Immunological principle of development of red blood cell alloimmunization in pregnancy, hemolytic disease of the fetus and prevention of RhD alloimmunization in RhD negative women.
DESIGN
Review article.
SETTING
Department of Obstetrics and Gynecology, Palacky University Olomouc, Faculty of Medicine and Dentistry, University Hospital Olomouc. Methods, results: Every person exposed to a foreign red blood cell antigen (erythrocyte antigen) develops an antibody. If the contact with a foreign erythrocyte antigen occurs during pregnancy, the erythrocyte alloimmunization of the pregnant woman develops and, due to antibodies crossing through the placenta also Haemolytic disease of the foetus and newborn (HDFN) can occur. Antibodies are made by pregnant woman's immune system and their quantity and quality depend on many factors. Their function is to eliminate foetal "foreign" erythrocytes. Ways of elimination of antibody-labelled foetal erythrocytes are the same in the bloodstream of pregnant women and foetuses/newborns and their principle is type II hypersensitivity (cytotoxic), according to the Coombs and Gell classification. Severe forms of HDFN can lead to increased perinatal morbidity and mortality. Prevention of the development of RhD alloimmunization and severe forms of HDFN is based on the administration of polyclonal immunoglobulin (Ig) G anti-D in all potentially sensitizing events. It is assumed that the mechanism of anti-D IgG action is based on the rapid removal of the antigen by antibody overflow, and on antibody mediated immune suppression (AMIS). However, the exact immunological principle is not fully known yet.
CONCLUSION
This article describes the development of irregular antibodies, methods of foetal erythrocytes destruction and the mechanism of prevention of anti-D immunoglobulin from the immunological point of view.
Topics: Erythroblastosis, Fetal; Erythrocytes; Female; Fetus; Humans; Infant, Newborn; Isoantibodies; Placenta; Pregnancy; Rh-Hr Blood-Group System; Rho(D) Immune Globulin
PubMed: 33711901
DOI: No ID Found -
Vox Sanguinis Mar 2022Orthotopic liver transplantation (OLT) has been associated with high blood transfusion requirements. We evaluated the transfusion needs and frequency of alloimmunization...
BACKGROUND AND OBJECTIVES
Orthotopic liver transplantation (OLT) has been associated with high blood transfusion requirements. We evaluated the transfusion needs and frequency of alloimmunization to RBC antigens among OLT recipients pre- and post-transplantation.
MATERIALS AND METHODS
We reviewed the medical records of patients who underwent a first OLT between January 2007 and June 2017. Transfusions given only during the perioperative period, defined by 1 week before OLT until 2 weeks following OLT, were included in this study. Records were reviewed in June 2019 for updated antibody testing results.
RESULTS
A total of 970 patients underwent OLT during the study period. The median age of patients was 57 years; 608(62.7%) were male. During the perioperative period, transfused patients received an average of 10.7 (±10.7) RBC units, 15.6 (±16.2) thawed plasma units and 4.1 (±4.3) platelet units. At the time of OLT, a total of 101 clinically significant RBC alloantibodies were documented in 58(5.98%) patients. Fifty-three of these antibodies were directed against Rh blood group antigens. Twenty-two (37.9%) patients had more than one alloantibody. Patients with alloimmunization before OLT (N = 58) received perioperatively comparable number of RBCs to non-alloimmunized patients (10.5 ± 10.6 vs. 9.6 ± 10.7; p = 0.52). There was no significant difference in perioperative or intraoperative RBC transfusion between patients with one alloantibody and those with multiple alloantibodies. Only 16 patients (16/737; 2.17%) developed new alloantibodies at a median of 61 days after OLT. The overall alloimmunization rate was 9.8% (72/737), and female patients were more likely to be alloimmunized.
CONCLUSION
Blood transfusion requirements in OLT remain high. However, the rate of RBC alloimmunization was not higher than the general patient population.
Topics: Blood Group Antigens; Blood Transfusion; Erythrocytes; Female; Humans; Isoantibodies; Liver Transplantation; Male; Middle Aged
PubMed: 34387366
DOI: 10.1111/vox.13190 -
The Journal of Heart and Lung... Aug 2021The microbiome is an environmental factor in intricate symbiotic relationship with its hosts' immune system, potentially shaping anticancer immunity, autoimmunity, and... (Review)
Review
The microbiome is an environmental factor in intricate symbiotic relationship with its hosts' immune system, potentially shaping anticancer immunity, autoimmunity, and transplant responses. The focus of this review is to discuss recent findings tying the microbiota to transplant outcomes and alloimmunity. The microbiota changes dynamically following transplantation, but whether these changes affect transplant outcomes can be difficult to parse out. New data reveal effects of the microbiota locally, as well as systemically, depending on the mucosal/epithelial surface colonized, the specific commensal communities present and the nature of microbial-derived molecules produced. These complex interactions result in the microbiota potentially impacting transplantation at different levels, including modulation of donor and/or recipient cells, alterations in the priming and/or effector phases of the alloimmune response, availability or metabolism of immunosuppressive drugs, transplant fate or post-transplant complications.
Topics: Adaptive Immunity; Graft Rejection; Humans; Microbiota; Organ Transplantation; Transplantation Tolerance
PubMed: 34030971
DOI: 10.1016/j.healun.2021.04.004 -
Transfusion and Apheresis Science :... Oct 2021The status of red blood cell alloimmunization in patients with constitutional anemias including hemoglobinopathies is not known in Norway. The study objective was to...
BACKGROUND AND OBJECTIVES
The status of red blood cell alloimmunization in patients with constitutional anemias including hemoglobinopathies is not known in Norway. The study objective was to investigate the impact of a strategy based on phenotype-matching for C, c, E, e, K, Jka, Jkb, Fya, Fyb, S and s on alloimmunization.
MATERIALS AND METHODS
We reviewed transfusions of 40 patients retrospectively using the computerized blood bank management system and medical records; including diagnosis, age at start of transfusion therapy, gender, number and age of packed red blood cell units transfused, follow-up time, phenotypes of the donors and patients, antigen-negative patients exposed to antigen-positive packed red blood cell units, transfusion reactions and alloantibody specificities.
RESULTS
Forty patients received 5402 packed red blood cell units. Alloimmunization frequency was 20 % for the whole group, being 7%, 25 % and 30 % in patients with sickle cell disease (n = 14), thalassemia (n = 16) and other conditions (n = 10), respectively. The alloantibodies detected were anti-E, -c, -C, -Cw, -K, -Jka and -Lua.
CONCLUSION
Good communication between the clinicians and the transfusion services is essential for successful management of patients with constitutional anemias. Providing full phenotype-matched units was not always possible. Extended pheno-/genotyping before the first transfusion and providing antigen-negative units for antigen-negative patients for at least C, c, E and K in every red cell transfusion would probably have reduced the alloimmunization rate. Non-phenotype-matched transfusions seem to be the main reason for alloimmunization. Finding markers for identifying responders prone to alloimmunization will ensure targeted transfusion strategies.
Topics: Adolescent; Adult; Anemia, Diamond-Blackfan; Anemia, Sickle Cell; Blood Group Antigens; Blood Transfusion; Child; Erythrocyte Transfusion; Erythrocytes; Fanconi Anemia; Female; Genotype; Humans; Isoantibodies; Male; Norway; Phenotype; Retrospective Studies; Thalassemia; Transfusion Reaction; Young Adult
PubMed: 34420880
DOI: 10.1016/j.transci.2021.103257 -
Vox Sanguinis Sep 2022There is a varied prevalence of red cell alloimmunization being reported from different parts of India. This study aimed to estimate the overall prevalence of... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND AND OBJECTIVES
There is a varied prevalence of red cell alloimmunization being reported from different parts of India. This study aimed to estimate the overall prevalence of alloimmunization in India by performing a systematic review of the literature and to establish the most suitable antigen-matching strategy to reduce the red blood cell (RBC) alloimmunization rate among transfusion recipients.
MATERIALS AND METHODS
A systematic search of all the original articles published in English on RBC alloimmunization among transfusion recipients from India in MEDLINE, SCOPUS, CINAHL and Google Scholar bibliographic databases was conducted. After screening the articles as per inclusion/exclusion criteria, data extraction was done independently by two sets of investigators. Meta-analysis was performed by the binary random-effects model using the restricted maximum likelihood method.
RESULTS
A total of 44 studies on RBC alloimmunization, with a cumulative sample size of 309,986 patients, were grouped into hospital-based and multiply-transfused patients, which yielded a prevalence of 0.5 (95% confidence interval; 0.3-0.8) and 4.8 (95% confidence interval; 3.9-5.7) per 100 patients, respectively. As many as 1992 alloantibodies were identified among the 1846 alloimmunized patients. The most common antibody identified was anti-E (127; 31.99%), followed by anti-c (75; 18.89%) in multiply-transfused patients.
CONCLUSION
The rate of alloimmunization was 0.5 per 100 patients tested for antibodies and 4.8 per 100 patients receiving transfusion. Considering E- and c-antigen-matched red cells along with ABO and RhD matching may significantly reduce the overall occurrence of alloimmunization among Indian population who are transfusion-dependent.
Topics: Blood Group Antigens; Blood Transfusion; Erythrocytes; Humans; India; Isoantibodies
PubMed: 35608911
DOI: 10.1111/vox.13296 -
Anemia 2023The risk of developing transfusion-related complications, especially alloimmunization, is an ongoing concern for transfusion-dependent patients. It is important to...
INTRODUCTION
The risk of developing transfusion-related complications, especially alloimmunization, is an ongoing concern for transfusion-dependent patients. It is important to determine the rate of alloimmunization and autoimmunization in Al-Ahsa Region, Saudi Arabia, where sickle cell disease (SCD) and thalassemia incidence rates are the highest in Saudi Arabia.
METHODS
A cross-sectional study was conducted to review the transfusion history of patients with SCD and thalassemia at the King Fahad Hospital (KFH) in Al-Ahsa, Saudi Arabia. 364 transfusion-dependent patients were included in this study.
RESULTS
Alloimmunization rates in patients with SCD and thalassemia were 16.7% and 11.97%, respectively, while autoimmunization rates in patients with SCD and thalassemia were 5.3% and 0.7%, respectively. The most frequent alloantibodies among the study participants were against Kell, Rh blood group systems.
CONCLUSION
Blood transfusion-related alloimmunization and autoimmunization compromise the proper management of chronically transfused patients. Ideally, extended matched phenotyping should be implemented to prevent alloimmunization and reduce the risk of developing blood transfusion-related alloantibodies.
PubMed: 37152479
DOI: 10.1155/2023/3239960 -
Transfusion and Apheresis Science :... Feb 2020A diagnosis of fetal/neonatal alloimmune thrombocytopenia (FNAIT) is made if a platelet-specific antibody is detected in the mother and the fetus or newborn carries the... (Review)
Review
A diagnosis of fetal/neonatal alloimmune thrombocytopenia (FNAIT) is made if a platelet-specific antibody is detected in the mother and the fetus or newborn carries the cognate antigen. Some children will experience very low platelet counts or even intracranial hemorrhage with devastating consequences, whereas others are largely unaffected. At the moment, predictive tools to forecast the severity of FNAIT during pregnancy are not available and over- or under-treatment may put the mother or the fetus at risk. A number of potential modulators of FNAIT severity have been reported. Maternal immune responses differ in respect to the IgG subtype composition, the glycosylation pattern of the antibodies, their fine specificity, and their functional effects on platelets, the trophoblast, and endothelial cells. In addition, antibody levels are variable. The efficacy of IgG transfer and, on the fetal side, gender and inflammatory responses, were also investigated for their potential impact on FNAIT severity. These potential risk modulators are scrutinized for available experimental and clinical evidence. Antibody glycosylation and anti-endothelial activity are hot candidates which, most likely in conjunction with the antibody level, should be explored further as tools to stratify fetal risk.
Topics: Antigens, Human Platelet; Female; Humans; Integrin beta3; Pregnancy; Risk Assessment
PubMed: 31948913
DOI: 10.1016/j.transci.2019.102709