Maternal-fetal Incompatibility Research Articles

Inflammatory placental lesions are specifically observed in healthy oocyte donation pregnancies with extreme fetal-maternal incompatibility

IntroductionOocyte donation (OD) pregnancy is a risk factor for pre-eclampsia (PE). Due to a higher extent of fetal-maternal human leukocyte antigens (HLA) mismatching in OD pregnancies compared to naturally conceived (NC) and in vitro fertilization (IVF) pregnancies, the immune response in OD placentas is probably divergent and affects clinical outcomes. We hypothesized that placental pathology varies among diverse pregnancy conditions and is related to fetal-maternal HLA incompatibility. MethodsPlacental lesions were scored in four patient groups: OD-PE (n = 16), OD-healthy (n = 37), NC-PE (n = 45), and IVF-healthy (n = 17). All combinations were genotyped for HLA-A, -B, -C, -DR, and -DQ to calculate fetal-maternal HLA mismatches. Placentas showing chronic deciduitis with plasma cells were immunofluorescently stained with CD138 and the anti-inflammatory cytokine interleukin-10 (IL-10). ResultsThe distribution and severity of placental lesions varied among groups. The OD-healthy group had the highest inflammation score and greatest extent of chronic deciduitis with plasma cells (p < 0.05). However, the majority of CD138+ plasma cells (90%) in OD-healthy group expressed IL-10, in contrast to the OD-PE group (58%). The OD-healthy group was separated into semi-allogeneic (≤5 HLA mismatches) and fully allogeneic (>5 mismatches) subgroups. The elevated inflammatory pathology score and chronic deciduitis with plasma cells were found more often in the HLA-class-I fully allogeneic OD-healthy group than the IVF-healthy group (p < 0.05). DiscussionPlacental inflammatory lesions are most often present in uncomplicated OD pregnancies. Immune cells that infiltrate these lesions might play an immunosuppressive role to protect OD pregnancies from complications when facing a higher extent of fetal-maternal HLA mismatching.

The need for neonatal jaundice screening awareness in the Pakistani population: short communication.

Neonatal jaundice is a common illness that affects around 80% of preterm and 50-60% of full-term newborn infants. It is one of the most common causes of neonatal death. Neonatal jaundice may be physiological or pathological. Physiologic jaundice is far more common than pathologic jaundice and accounts for most hyperbilirubinemia. Physiologic jaundice in neonates is due to greater hemoglobin breakdown compared to bilirubin clearance. While pathological jaundice occurs due to various infections, drug toxicity, inborn enzyme deficiencies, Rhesus fetal-maternal incompatibility, hypothyroidism, and congenital biliary duct obstruction diseases. In many parts of the world, midwives, and nurses perform spontaneous vaginal deliveries and they only rely on visual screening for neonatal jaundice. However, this is not reliable, especially for newborns having darker skin. Educating the mothers on screening for early detection of neonatal jaundice and seeking medical treatment in a country like Pakistan, which is considered a high-risk population, is crucial. Also, as most females give birth at home, hence, midwives' knowledge about neonatal jaundice also needs to be improved.

Live birth prevalence of hemolytic disease of the fetus and newborn in the United States from 1996 to 2010

Hemolytic disease of the fetus and newborn (HDFN) is mediated by maternal alloantibodies, a consequence of immune sensitization during pregnancy with maternal-fetal incompatibility with ABO, Rhesus factor (Rh), and/or other red blood cell antigens. RhD, Kell, and other non-ABO alloantibodies are the primary cause of moderate to severe HDFN, whereas ABO HDFN is typically mild. HDFN live birth prevalence owing to Rh alloimmunization among newborns in the United States was last estimated to be 106 per 100,000 births in 1986. HDFN live birth prevalence owing to all alloantibodies was estimated to be 817 to 840 per 100,000 in Europe. There is a need for updated prevalence estimates in the United States and a better understanding of disease demographics, severity, and treatments. This study aimed to estimate the live birth prevalence of HDFN and the proportion of severe cases of HDFN in the United States, to describe the associated risk factors, and to compare the clinical outcomes and treatments among healthy newborns, newborns with HDFN, and newborns who are sick without HDFN using a nationally representative hospital discharge database. In this retrospective, observational cohort study, we used data from the 1996 to 2010 National Hospital Discharge Survey to identify live births, defined by inpatient visits with the newborn flag, with and without a diagnosis of HDFN across 200 to 500 sampled hospitals (≥6 beds) per year. Patient and hospital characteristics, alloimmunization status, disease severity, treatment, and clinical outcomes were evaluated. Frequencies and weighted percentages were calculated for all variables. Logistic regression was used to compare the characteristics between newborns with HDFN and other newborns using odds ratios. Of 480,245 live births identified, 9810 HDFN cases were recorded. When weighted to the United States population, this corresponded to a live birth prevalence of 1695 per 100,000 live births. Compared with other newborns, newborns with HDFN were more likely to be female, Black, living in the South (vs the Midwest or West), and treated at larger (>100 beds) and government-owned hospitals. ABO and Rh alloimmunization accounted for 78.1% and 4.3% of newborns with HDFN, respectively, whereas HDFN caused by other antigens, such as Kell and Duffy, accounted for 17.6% of the cases. Among newborns with HDFN, 22% received phototherapy, 1% received simple transfusions, and 0.5% received exchange transfusions or intravenous immunoglobulin. Newborns affected by HDFN caused by Rh alloimmunization were more likely to require medical interventions, including simple or exchange transfusions, and more likely to be delivered by cesarean delivery. Overall, HDFN was associated with a longer hospital length of stay in the neonatal intensive care unit when compared with healthy and other sick newborns, a higher rate of cesarean delivery, and a higher rate of nonroutine discharge than healthy newborns. Overall, the live birth prevalence of HDFN was higher than those previously reported, whereas Rh-induced HDFN live birth prevalence was similar to those previously reported. HDFN live birth prevalence owing to Rh alloimmunization decreased over time, likely because of continued Rh immune globulin prophylaxis. Treatment patterns for newborns with HDFN and the comparative clinical outcomes when compared with healthy newborns confirm the continued clinical needs of this population.

Human neutrophil antigen-1, -3, -4, and -5 allele and genotype frequencies in the Croatian blood donor population and their clinical significance.

Human neutrophil antigens (HNAs) and antibodies play an important role in allo- and autoimmunity associated with immune neutropenia and transfusion reactions. The aim of this study was to determine the HNA-1, -3, -4 and -5 allele and genotype frequencies in the Croatian blood donor population to assess the role of HNA-1, -3, -4, and -5 alleles in the development of neonatal alloimmune neutropenia and antibody-mediated transfusion-related acute lung injury. A total of 371 blood samples from unselected healthy blood donors were analyzed. Samples from all 371 donors were genotyped for HNA-1, samples from 160 donors were genotyped for HNA-3, and samples from 142 donors were genotyped for HNA-4 and HNA-5 using the polymerase chain reaction with sequence-specific primers (PCR-SSP) method. The frequencies of the FCGR3B*01, FCGR3B*02 and FCGR3B*03 HNA-1 alleles were 0.393, 0.607 and 0.022, and of the SLC44A2*01 and SLC44A2*02 HNA-3 alleles 0.781 and 0.219, respectively. The frequencies of the ITGAM*01 and ITGAM*02 HNA-4 alleles were 0.796 and 0.204, and of the ITGAL*01 and ITGAL*02 HNA-5 alleles 0.718 and 0.282, respectively. These are the first results on the HNA allele and genotype frequencies in the Croatian blood donor population. We observed no deviations from previous reports on Caucasian populations. Determination of the HNA antigen frequencies in the population is important to estimate the risk of alloimmunization to HNA, especially the risk of fetal-maternal incompatibility and alloantibody production by transfusion of the HNA incompatible blood components.

Fetal-maternal incompatibility in the Rh system. Rh isoimmunization associated with hereditary spherocytosis: case presentation and review of the literature.

Next to A and B antigens, agglutinogen D exhibits the highest immunogenicity. Following the transfusion of D-positive red blood cells (RBCs), almost 80% of D-negative recipients develop anti-D antibodies (Abs). Subsequently, anti-D immunization further promotes the synthesis of Abs towards other blood group antigens in or outside the Rh system. The D antigen is also involved in 95% of cases of hemolytic disease of the newborn. Transfusions, hemotherapy, grafts, and obstetric history (abortions, ectopic pregnancy, births) are all risk factors for Rh isoimmunization. In the case of ABO compatibility between mother and fetus, Rh-positive fetal RBCs that have reached the maternal bloodstream are not destroyed by group agglutinins, and Rh antigenic sites are not hidden by the maternal immune system. But a Rh-negative mother with a homozygous Rh-positive husband will certainly have a Rh-positive fetus. As it has an irreversible evolution, the Rh isoimmunization once installed cannot be influenced in the sense of decreasing the Ab titer, therefore, injectable globulin has no effect. A particular case was that of a newborn with Rh system incompatibility associated with hereditary spherocytosis The clinical balance at birth reflects the severe jaundice of the female newborn of 3140 g, gestational age 38∕39 weeks, extracted by lower-segment transverse Caesarean section, with a double loop nuchal cord, Apgar score 8. Because the jaundice was severe and atypical (face and upper chest), we considered the possibility of coexistence of hemolytic disease of the newborn by Rh blood group incompatibility associated with hereditary spherocytosis, as it turned out to be true and mentioned. Changes in genes encoding proteins in the structure of the RBC membrane have amplified hemolysis induced by maternal-fetal isoimmunization in the Rh system. Massive hemolysis accentuated by congenital spherocytosis, confirmed later, imposed blood transfusion and dynamic monitoring.

Implementation of Low Titer Whole Blood for French overseas operations: O positive or negative products in massive hemorrhage?

Massive hemorrhage is the leading preventable cause of death during military operations. During these operations, the delay between initial treatment and arrival at a surgical facility is considerably longer than in Metropolitan settings. This increased prehospital period requires the availability of blood products during the prehospital stage and justifies the availability of Low Titer Whole Blood (LTOWB) for surgical facilities. This product is a fully authorized labile blood product processed by the French Military Blood Institute according to French regulations. Its shelf life is 21 days when stored between 2 and 6°C. It provides the three products necessary for the transfusion management of war injuries in a single product and in physiological proportions. The low anti-A and anti-B titers (<1/64) make LTOWB compatible with any recipient. However, the RhD antigen remains an issue due to its potential harm in cases of transfusion to a D-negative childbearing-age woman due to the potential risk of fetal-maternal incompatibility. This risk must be balanced with the availability of D-negative blood products. Considering the epidemiology of war injuries and LTOWB use guidelines, in addition to the current knowledge on anti-RhD fetal-maternal alloimmunization, the harm-benefit assessment favors the use of RhD-positive LTOWB during overseas operations. Follow-up of childbearing recipients and setup of countermeasures to prevent alloimmunization in those cases remain key points of transfusion safety.

Are HPA-5b antibodies a significant cause of FNAIT and associated bleeding or merely an incidental finding?

Are HPA-5b antibodies a significant cause of FNAIT and associated bleeding or merely an incidental finding?

Prevalence of Neonatal Jaundice in the Zone Hospital of Suru-Lere at Cotonou (Benin)

Objectives: Summarize the data for better management of jaundice in neonatology Patients and methods: This was a study on 842 Beninese newborns aged 0 to 7 days hospitalized over the period from June 2014 to June 2015. Results: On 842 newborns, 170 were neonatal jaundice franc is 20.19%. The ratio is in favor of boys (1.8); jaundice is early in 2.35% of cases. Etiologies are represented by physiological jaundice, infection, maternal-fetal incompatibility erythrocyte. The use of exchange transfusion was required in 5.29% of cases. The rest of the treatment was dominated by intensive phototherapy and / or associated with conventional etiological treatment. Prematurity and infection are the main risk factors identified in our series. Conclusion: Jaundice is a common condition of course, but we draw attention to the importance of the rate of neonatal jaundice in our context related primarily to the non-monitoring of pregnancies, early discharge of maternity and consultations late.&#x0D; Tags: jaundice, prevalence, newborn, spectrophotometer, bilirubin.

Feto-Maternal Incompatibility in the ABO System at EHS Nouar Fadela

Introduction: Fetal-maternal blood incompatibility (IFM) is one of the major causes of neonatal jaundice that can progress to kernicterus. Objective: To determine the frequency and the titre of anti-A and anti-B hemolysins in women in the immediate postpartum period as well as the associated risk factors. Patients and methods: The study is cross-sectional conducted in mothers and their newborns from January 1 to October 31, 2019. ABO blood groups were determined in all participants. In mothers, research and titration of hemolysins was done. Pearson's chi-squares were used for statistical tests. A p value <0.05 was a statistically significant difference. Results: We recorded 120 cases of fetal-maternal ABO incompatibility. Anti-A, anti-B and anti-AB hemolysins were found in 9.4%, 17.9% and 66.7% of cases, respectively. the highest titers were those of anti-B hemolysins (43%). Risk factors included: multiparity, advanced age and ABO fetal-maternal incompatibility. Conclusion: It is necessary to introduce systematic research for hemolysins among immunohematological monitoring tests in pregnant women and their implication in newborns.

Maternal-fetal Blood Major Crossmatching in Merino Sheep.

To determine the incidence of ex vivo incompatibility between ovine maternal RBCs and fetal plasma, we performed cross-matching of blood samples from ewes and from lambs delivered by cesarean section. Twenty-one date-mated singleton pregnant Merino ewes were anesthetized for cesarean delivery of the fetus. At the time of delivery, paired maternal and fetal blood samples were collected and subsequently separated for storage as packed red blood cells and fresh frozen plasma. Gel column major cross matching was performed within 2 wk. All fetus-dam crossmatches were major crossmatches, combining fetal (recipient) plasma with dam (donor) RBCs. 172 individual dam-dam cross matches were performed. Two of these tests were incompatible (1.2%). In addition, 19 fetal blood samples collected immediately after cesarean delivery were crossmatched with 21 maternal samples to generate 174 maternal-fetal individual cross matches. No maternal-fetal incompatibility reactions were observed. The results of this study demonstrate that all maternal donors and fetal recipients were compatible. In addition, the incidence of an incompatible crossmatch between adult ewes was 1.2%. These data suggest that lambs may not be born with antibodies against other blood types, but rather may acquire such antibodies at some time during early life. In addition, these data suggest the risk of incompatibility reactions between ewes of a similar breed and from a single farm of origin is very low.

Prevalence of ABO Incompatibility and its effect on Neonates Hyperbilirubinemia

Introduction: Neonatal jaundice is one of the most common causes of fetus morbidity. It is a worldwide condition occurring in up to 80% of preterm and 60% of term neonate in first life’s week. maternal-fetal ABO incompatibility occurs when the fetus has blood group A or B And his mother has blood group O. Material and Methods: The data was collected from hospital case file after newborn examination by use questionnaire method on a sample size of 75 term neonates with jaundice. This study included neonate with hyerbilirubinemia needing phototherapy and/or exchange transfusion duo to maternal-fetal ABO incompatibility or other causes of neonatal jaundice. Results: In this study the neonatal jaundice was more common in male than in female. highly significant difference in gestational age, neonate age at admission, time of initiation of breast feeding, presence of hemolysis was presented among the study neonates. Highest percentage of study neonates had blood group O and A (41.3 and 34.7%) respectively while the lowest had blood group AB (1.3%). The ABO incompatibility reported with thirteen neonates (17.33%), neonates had blood group A and 6 neonates had blood group B. The present study showed that mean serum bilirubin and hemoglobin levels were close approximately for ABO compatible and incompatible neonates. Majority of study neonates needs the duration of phototherapy for =24 hours. Conclusion: This study revealed that the prevalence of neonatal ABO incompatibility was (17.33%), and there was no significant difference in mean of serum bilirubin and hemoglobin between the ABO compatible and incompatible neonates.

Neonatal Bilirubin Encephalopathy: Study of 30 Cases at Albert Royer National Children Hospital of Dakar

Introduction: Unconjugated bilirubin jaundice is a common symptom in neonatal period. In some babies, excessive serum bilirubin concentrations can place them at risk of acute bilirubin encephalopathy (BE) when the unconjugated pigment crosses the blood-brain barrier. Our study aimed to describe epidemiology, diagnosis and prognosis of BE at the Neonatology Department of Albert Royer Children’s Hospital of Dakar. Materials and Methods: It was a retrospective, descriptive study of cases of BE from January 1, 2015 to June 30, 2019. Obstetric and perinatal data as well as postnatal jaundice data (onset time, associated signs, signs of encephalopathy, treatment and evolution) were collected and analyzed by SPSS software version 2.0. Almost all newborns (27 cases; 90%) were exclusively breastfed. At admission, all children exhibited blunt jaundice and signs of encephalopathy dominated by the abolition of archaic reflexes (76.7%), low suction (22 cases; 73.3%), central apnea (12 cases, 40%). The mean serum bilirubinemia was 322 mg/litre. Neonatal infection (10 cases; 33.3%) and fetal-maternal incompatibility (16 cases; 53.3%) were the main causes. All children received intensive phototherapy and exsanguino transfusion was performed for 7 newborns (23.3%). Nine children died (30% mortality rate). Conclusion: Only better organisation of perinatal care with enhanced postnatal follow-up can reduce the incidence of EB.

Management and outcome of pregnancies in women with red cell isoimmunization: a 15-year observational study from a tertiary care university hospital

BackgroundThe aims of this study were to determine the prevalence of the different anti-erythrocytic alloantibodies, to describe pregnancy outcomes according to a low-risk and high-risk classification for fetal anemia and to determine the factors that influence adverse perinatal outcomes.MethodsThis retrospective observational study included women referred to our center following the identification of maternal anti-erythrocytic alloantibodies between 2002 and 2017. Pregnancies were classified as high risk for fetal anemia in cases with clinically significant antibodies, no fetal-maternal compatibility and titers ≥1:16 or any titration in cases of Kell system incompatibility. In high-risk pregnancies, maternal antibody titration and the fetal middle cerebral artery peak systolic velocity (MCA-PSV) were monitored. Low-risk pregnancies underwent routine pregnancy follow-up.ResultsMaternal antibodies were found in 337 pregnancies, and 259 (76.9%) of these antibodies were clinically significant. The most frequent antibodies were anti-D (53%) and anti-K (19%). One hundred forty-three pregnancies were classified as low risk for fetal anemia, 65 (25%) cases were classified as no fetal-maternal incompatibility, 78 had clinically nonsignificant antibodies, 4 (2.8%) resulted in first-trimester pregnancy loss, and 139 (97.2%) resulted in livebirths. Of the 194 high-risk pregnancies, 38 had titers < 1:16 (resulting in 38 livebirths), and 156 had titers ≥1:16 or anti-K antibodies. In the last group, 6 cases miscarried before 18 weeks, 93 had a MCA-PSV < 1.5 multiples of the median (MoM), resulting in 3 perinatal deaths that were unrelated to fetal anemia, one termination and 89 livebirths; and 57 had a MCA-PSV > 1.5 MoM, resulting in 3 intrauterine deaths, 6 terminations and 48 livebirths. Ninety-two intrauterine transfusions were performed in 45 fetuses (87% anti-D). Adverse outcomes were related to a MCA-PSV > 1.5 MoM (p < 0.001), hydrops (p < 0.001) and early gestational age at first transfusion (p = 0.029)ConclusionAnti-D remains the most common antibody in fetuses requiring intrauterine transfusion. A low or high-risk classification for fetal anemia based on the type of antibody, paternal phenotype and fetal antigen allows follow-up of the pregnancy accordingly, with good perinatal outcomes in the low-risk group. In the high-risk group, adverse perinatal outcomes are related to high MCA-PSV, hydrops and early gestational age at first transfusion.

Fetal-Neonatal Alloimmune Thrombocytopenia (FNAIT): Guidance to Reduce the Risk of Intracranial Bleeding

IntroductionFNAIT is associated with severe bleeding, especially intracranial hemorrhage (ICH), in the fetus and/or newborn. More than 75% of ICHs occur in utero and up to 50% before 32 weeks gestation. The consequences of ICH include death (35%) or serious neurological sequelae in survivors (83%). FNAIT requires prompt identification and treatment antepartum, postpartum and in subsequent pregnancies. An international panel was convened by the International Collaboration for Transfusion Medicine Guidelines (ICTMG) to develop evidence based recommendations for diagnosis and management of FNAIT.MethodsThe international panel consisted of specialists in adult and pediatric hematology, maternal fetal medicine (MFM), neonatology, methodology, transfusion medicine, and a patient representative. Clinical questions were developed for diagnostic testing, antenatal screening and management, and postnatal interventions. A systematic search for articles published between 1946 and June 2017 in MEDLINE, EMBASE and Cochrane was conducted. Recommendations were formulated based on the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) method which incorporates the quality of the evidence, benefits and risks, and resource utilization. Web conferences and electronic correspondence were used to discuss the results of the systematic reviews and formulate recommendations. Considerations for clinical practice such as dosing of intravenous immunoglobulin (IVIG) and corticosteroids were detailed. Electronic surveys were sent to all members to assess agreement with recommendations. The final guidance document was sent to maternal fetal, hematology and pediatric societies for comments.ResultsThree systematic reviews (antenatal management, postnatal management and use of laboratory investigations to identify pregnancies at risk) were developed. Antenatal recommendations: Women with FNAIT in a previous pregnancy or sisters of women with FNAIT should be referred to MFM centers. Fetal HPA typing (e.g. HPA-1a/1b) should be performed in HPA-immunized pregnant women when the paternity is unknown or the partner is heterozygous or unavailable for testing. Prenatal HPA-1 typing should preferentially be performed by a non-invasive method e.g. cell-free fetal DNA (cffDNA) in maternal plasma if adequately quality assured. Antenatal IVIG administration to the mother commencing at 12-16 weeks gestation should be offered to all women in a subsequent pregnancy with maternal fetal incompatibility who have had a previous fetus or neonate with FNAIT related ICH. For all other pregnancies with a previous neonate with FNAIT (without ICH), administering antenatal IVIG to the mother should be discussed prior to a subsequent pregnancy or when pregnancy with maternal fetal incompatibility is confirmed. If corticosteroids are used with IVIG, dexamethasone should not be used because of the associated risk of oligohydramnios. Postnatal recommendations: HPA-selected platelets should be made available at delivery for potentially affected infants to increase the neonatal platelet count. If HPA-selected platelets are not immediately available, unselected platelets should be used. In the presence of life-threatening neonatal hemorrhage such as intracranial or gastrointestinal bleeding, platelets should be transfused to maintain platelet counts above 50 to 100x109/L for at least 7 days. In the absence of life-threatening bleeding in a neonate such as intracranial or gastrointestinal bleeding, platelets should be transfused to maintain a platelet count above 30x109/L.ConclusionsThe intent of this guidance document developed from systematic reviews is to promote best practices in the management of FNAIT. The guideline development group developed algorithms for treatment, podcasts for physicians and patients, pamphlets for patients and a slide set to assist with the implementation of recommendations into practice. This expert panel identified key areas for future research. One is the optimal approach to antenatal management of the next affected pregnancy. Developing biomarkers of fetal severity would be critical to this endeavor. In addition, creating comprehensive screening to identify HPA-1b1b women at risk of FNAIT would advance successful prevention of this disease. DisclosuresBakchoul:German Research Society (DFG): Research Funding; Aspen Germany gGmbH, CLS Behring, Stago gGmbH: Honoraria; Robert Bosch gGmbH: Research Funding. Kjaer:Prophylix Pharma: Equity Ownership. Kjeldsen-Kragh:Prophylix Pharma: Equity Ownership. Oepkes:Towards routine HPA screening in pregnancy: Research Funding. Bussel:Uptodate: Honoraria; Rigel: Consultancy, Research Funding; Novartis: Consultancy, Research Funding; Protalex: Consultancy; Amgen Inc.: Consultancy, Research Funding; Prophylix: Consultancy, Research Funding; Momenta: Consultancy. Arnold:Bristol Myers Squibb: Research Funding; Amgen: Consultancy, Research Funding; UCB: Consultancy; Novartis: Consultancy, Research Funding; Bristol Myers Squibb: Research Funding; UCB: Consultancy; Novartis: Consultancy, Research Funding; Amgen: Consultancy, Research Funding. Savoia:Neonatal Alloimmune Thrombocytopenia Registry of the Transfusion Outcomes Research Collaborative (TORC) Australia: Membership on an entity's Board of Directors or advisory committees.

Severe neonatal thrombocytopenia due to fetomaternal anti-A alloimmunization: A case report

Severe neonatal thrombocytopenia due to fetomaternal anti-A alloimmunization: A case report

Prophylaxie anti-D dans l’incompatibilité fœto-maternelle érythrocytaire en Tunisie

Generalization of postnatal prophylaxis using anti-D immunoglobulins decreased the incidence of erythrocyte fetal-maternal incompatibility (EFMI) in the Rhesus system. Few recent studies have investigated the situation of anti-D prophylaxis in Tunisia and its effects on maternal and neonatal health. The aim of this study was therefore to analyze the situation of anti-D prophylaxis in Tunisia to detect defects and propose solutions. We conducted a retrospective descriptive study of IFME cases in the rhesus system in the Department of Medicine and Neonatal Resuscitation of the Tunis Maternity and Neonatology Center (CMNT) during an 8-year period from 1January 2006to 31December 2015. We collected 51cases of IFME. The prevalence of IFME was 3.4per 10000live births; 41% of the patients were transferred in utero and they were from the northwest of the country (17%). The rate of women with a history of at least one spontaneous miscarriage (SCF) was 45%. In 42% of the cases, pregnancies were monitored at local clinics. The search for irregular agglutinins (RAI) was performed in 86% of the women studied. RAI was positive in 97% of the cases. Anti-D prophylaxis was correctly performed in only 27% of the cases. The systematic prophylaxis of the third trimester and a systematic Kleihauer test must be combined with postpartum prophylaxis to better identify dysfunctions and improve the application of the recommendations.

Hemolytic disease by isoimmunization in Rh and ABO systems in newborns. A clinical study

The following study aims are to establish the incidence of the hemolytic disease, the risk factors, clinical forms and the main therapeutic measures in the newborns of Constanta County Emergency Hospital over a period of two years, on a group of 76 newborn infants diagnosed with the Rh and ABO hemolytic disease incompatibility. Out of the76 cases of maternal-fetal incompatibility, 39 newborn infants presented Rh isoimmunization, 20 cases presented ABO isoimmunization, and 17 cases presented group and Rh double isoimmunization. Pathological jaundice was presented in all cases, occurred within 24 hours since birth. Based on the classification of clinical signs and laboratory investigations, patients could be divided in two clinical forms of neonatal hemolytic disease: 9 cases with severe anemia at birth and 67 with severe jaundice and moderate anemia. In this cases, we recommend the use of the guide regarding Rh incompatibility in pregnancy which represents a modern and uniform approach of this pathology at national level, decreasing in this way the number of immunized patients during pregnancy.

Genetical study of mutation in maternal-fetal ABO incompatibility.

This study looked into a family involving a rare mother-child ABO blood type inconsistency and explored its genetic and molecular basis. In the family, the mother had type AB blood and the father was blood type B and they gave birth to a baby of blood type O. Their blood types were phenotypically identified by using different techniques, including micro-column gel test, immune inhibition test, absorption and elution tests. The sequences of all 7 exons of ABO allele from the core family members were determined by using PCR and clone-based sequencing. The loci of mutated gene were compared against normal human genes. The result showed that the mother's erythrocytes were agglutinable with monoclonal anti-A antibody (2+) and had agglutination reaction with anti-B antibody (4+). The mother's serum registered agglutination action with standard blood type A cells. The findings showed an ABO inconsistency. When domestic antibodies were used, the mother's erythrocytes yielded agglutination reaction with humanized anti-B serum (4+) and anti-B monoclonal antibody but were non-agglutinable with humanized anti-A serum and anti-A monoclonal antibody. Upon absorption and elution, the titer of anit-A antibody was 128 both before and after the absorption test, with no significant difference found between pre- and post-absorption values. Our results confirmed that the mother's allelic gene was type B and contained type A. The father's blood type was type B, and son's blood type was type O. Clone-based sequencing revealed that the mother carried a heterozygous gene of B101.01 (ntA640→G)/O01, which contained an M214→V mutation that could express a weak expression of antigen A, resulting in blood type AB. However, their son did not have the M214→V mutation, which yielded a false ABO-inconsistency between him and his mother. We were led to conclude that type B gene with a M214→V mutation can encode both antigen B and weak antigen B that can lead to false ABO-inconsistencies.

Financial implications of RHD genotyping of pregnant women with a serologic weak D phenotype.

Hemolytic disease of the fetus and newborn, classically caused by maternal-fetal incompatibility of the Rh blood group D antigen, can be prevented by RhIG prophylaxis. While prophylactic practices for pregnant women with serologic weak D phenotypes vary widely, RHD genotyping could provide clear guidance for management. This analysis evaluated the financial implications of using RHD genotyping to guide RhIG prophylaxis among pregnant females. A Markov-based model was constructed to evaluate the costs of RHD genotyping for pregnant females with serologic weak D phenotypes to inform RhIG prophylaxis. Using a comparison strategy of managing these women conservatively as D-, direct medical costs were assessed over 10- and 20-year periods for a simulated population of US women. One-way and probabilistic sensitivity analyses were used to assess the robustness of conclusions. Using base-case variables, RHD genotyping for pregnant women with serologic weak D phenotypes is expected to marginally reduce overall costs. RHD genotyping these patients, rather than conservatively managing them as D-, would be cost-saving when the cost of genotyping is below $256. Genotyping would decrease net costs among non-Hispanic Caucasian females (-$0.17/pregnancy), but would increase costs among non-Hispanic African Americans (+$0.51/pregnancy), non-Hispanic American Indian/Alaskans (+$0.10/pregnancy), and Hispanics (+$0.37/pregnancy). Incorporating RHD genotyping would not significantly impact costs among Asians and Hawaiians/Pacific Islanders. Using RHD genotyping to guide RhIG prophylaxis among pregnant women with serologic weak D phenotypes may be clinically beneficial without increasing overall costs.

Neonatal Alloimmune Neutropenia Due to Maternal Alloimmunization Against Human Neutrophil Alloantigen-1 and -3

Introduction: Neonatal alloimmune neutropenia (NAN) is a potentially lethal disorder that results from maternal alloimmunization to human neutrophil antigens (HNAs) present in the fetus. The alloantibodies more frequently involved in NAN are against the HNA-1 and -2 systems; however HNA-3, HNA-4 and HNA-5 systems have also been associated with cases of NAN. In this study we examined the frequency of neonatal neutropenia and investigated the presence of maternal anti-HNA-1, anti-HNA-3 and anti-HLA alloantibodies when neonatal neutropenia and maternal-fetal incompatibility to HNA-1 and HNA-3 systems were observed. Furthermore, we investigated the association between neutrophil alloimmunization and HLA-DRB1 alleles.Methods: A cross sectional study included samples from 10,000 unselected neonates born in 4 obstetric units in Sao Paulo City (Brazil). Neonatal neutropenia was defined as neutrophil count <1.5x109/L in cord blood. Genotyping studies were performed in 88 neutropenic newborns and their mothers (83 mothers with 3 pairs of twins and 1 triplet) by PCR-SSP technique for the detection of HNA-1a, -1b and -1c alleles and by PCR-RFLP technique for the detection of HNA-3a and -3b alleles; the PCR-RFLP technique amplifies the sequence for rs2288904 and the amplified product was digested with enzyme Taqα1 specific to nucleotide guanine that codifies the HNA-3a antigen (Lopes et al., Transfusion 2014;54(6):1619-21.). Serologic studies for detecting maternal HNA alloantibodies were performed in maternal-fetal incompatibility cases by granulocyte agglutination test (GAT) that was done in duplicate using a specific panel of donors previously genotyped for HNA-1 and HNA-3 systems. Anti-HLA-I/II antibodies were investigated in maternal serum, and all 83 mothers were genotyped for the HLA-DRB1 gene. Two control groups included mothers with maternal-fetal incompatibility but without alloantibodies, and healthy individuals.Results: Neonatal neutropenia was identified in 88 of 10,000 (0.9%) newborns in the studied population. Genotyping studies revealed 39/88 (44.3%) maternal-fetal HNA incompatibilities corresponding to 28/88 (31.8%) for HNA-1 and 13/88 (14.8%) for HNA-3. In 12/28 (42.9%) cases we found incompatibility for the HNA-1a allele; in 9/28 (32.1%) for HNA-1b; in 4/28 (14.3%) for HNA-1c; in 1/28 (3.6%) for both HNA-1a and -1c; and in 2/28 (7.1%) for both HNA-1b and -1c alleles. In all neutropenic cases related to HNA-3 system mothers were typed as HNA-3a/a and neonates as HNA-3a/b. Using the GAT, HNA alloantibodies were found in 21/39 (53.8%) mothers including 16/28 (57.2%) anti-HNA-1 and 5/13 (38.5%) anti-HNA-3b. The specificity of HNA-1 alloantibodies was confirmed in 9 cases for anti-HNA-1a and in 7 for anti-HNA-1b. Anti-HLA antibodies were detected in 6/16 GAT(+) maternal serum containing anti-HNA-1 and in 2/5 GAT(+) with anti-HNA-3. Two maternal-fetal incompatibility cases occurred concomitantly for HNA-1 and HNA-3 systems; however, only anti-HNA-3b alloantibodies could be identified using the panel of donors. HLA-DRB1 genotyping showed an increased frequency of HLA-DRB1*01 and HLA-DRB1*10 alleles in mothers with HNA incompatibility when anti-HNA were not found. A statistically significant difference was observed between these mothers with HNA incompatibility not alloimmunized and the healthy individuals (HLA-DRB1*01 p=0.0433; HLA-DRB1*10 p=0.0208).Conclusions: The observed frequency of neonatal neutropenia in Brazilians of 0.9% is similar to those described in North Americans and Europeans with a comparable positive serology rate of 53.8% more frequently due to the presence of anti-HNA-1 (76.2%). As for the best of our knowledge this is the first study reporting the presence of anti-HNA-3b alloantibodies in newborns with NAN (23.8%). The frequencies of the HLA-DRB1*01 and HLA-DRB1*10 alleles were increased in mothers with HNA incompatibility without HNA alloantibodies suggesting that such HLA-DRB1 alleles may confer protection against neutrophil alloimmunization in cases of maternal-fetal incompatibility for HNA systems involved with NAN. DisclosuresNo relevant conflicts of interest to declare.