Severe Cholestasis in Neonates with Hemolytic Disease of the Fetus and Newborn-A Case Report.

Hemolytic disease of the fetus and newborn (HDFN) may cause severe cholestasis with direct bilirubin concentrations reaching up to 50 times the upper limit of normal. This case report describes twins whose highest direct bilirubin concentrations were 32.2 mg/dL and 50.2 mg/dL, with no significant signs of hepatic impairment. The index pregnancy was complicated by Rhesus factor immunization with anti-D antibodies present in maternal serum, which caused fetal anemia requiring intrauterine blood transfusions. Complementary tests demonstrated Rhesus D alloimmunization as the sole cause of cholestasis. To the best of our knowledge, this is the first study to describe such elevated direct bilirubin concentrations caused by HDFN.

Significance of immunohematologic testing in mother and newborn ABO incompatibility.

The aim of this study was to define risk factors for jaundice and anemia in newborns with a positive direct antiglobulin test (DAT) and/or with an incompatible crossmatch due to ABO incompatibility between mother and newborn. ABO incompatibility has become a more significant cause of hemolytic disease of the fetus and newborn since the introduction of effective anti-D prophylaxis. The condition is common and, if clinically significant at all, causes only mild jaundice, which can be treated with phototherapy (PT). However, rare and serious presentations, requiring transfusion therapy, have been noted. Clinical, laboratory, and immunohematologic data were collected retrospectively from medical records of ABO-incompatible newborns and their mothers over a 5-year period (2016-2020) from University Hospital Centre Zagreb. Two groups of newborns were compared: those who needed medical intervention because of hyperbilirubinemia or anemia and those who did not. Within the group of newborns requiring intervention, we also compared those with A and B blood groups. Over the 5-year period, 72 of 184 (39%) newborns required treatment. The treatment was PT in 71 (38%) newborns and erythrocyte transfusion in 2 (1%). In 112 (61%) newborns, ABO incompatibility was an accidental finding while performing blood group typing; these newborns did not require any therapy. In conclusion, we found a statistical, but not clinically significant, difference between the groups of treated and untreated newborns, related to the mode of delivery and DAT positivity within hours of delivery. There were no statistically significant differences in characteristics between the groups of treated newborns, except for two newborns with blood group A who received erythrocyte transfusions.

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

BACKGROUND: 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. OBJECTIVE: 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. STUDY DESIGN: 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. RESULTS: 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. CONCLUSION: 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.

Hemolytic disease of the fetus and newborn mediated by anti-Dia in a U.S. hospital.

Dia is one of the most clinically significant low-prevalence antigens in the Diego blood group system, since antibodies to Dia have, albeit rarely, been implicated in hemolytic transfusion reactions and hemolytic disease of the fetus and newborn (HDFN). Given the geographical association, most anti-Dia HDFN cases have been reported in Japan, China, and Poland. We describe a case of HDFN in a neonate born to a 36-year-old G4P2012 woman of self-identified Hispanic ethnicity and of South American descent with multiple negative antibody detection tests in a U.S. hospital. Upon delivery, a cord blood direct antiglobulin test was positive (3+ reactivity), and neonatal bilirubin levels were moderately elevated, but phototherapy and transfusion were not required. This case highlights a rare, unexpected cause of HDFN in the United States secondary to anti-Dia, given the near-universal absence of this antigen and antibody in most U.S. patient populations. The case also demonstrates the need for awareness of antibodies to antigens that are considered "low-prevalence" in most populations but that might be encountered more frequently in specific racial or ethnic groups and may require more extensive testing.

History and current standard of postnatal management in hemolytic disease of the fetus and newborn.

Since the discovery of the Rh blood group system in 1940, a greater understanding of hemolytic disease of the fetus and newborn (HDFN) was gained. In the years thereafter, researchers and clinicians came to the current understanding that fetal and neonatal red blood cells (RBC) are hemolyzed by maternal alloantibodies directed against RBC antigens potentially leading to severe disease. Preventative measures, such as Rhesus(D) immunoprophylaxis (RhIG), have greatly decreased the prevalence of Rh(D)-mediated HDFN, although a gap between high-income countries and middle- to low-income countries was created largely due to a lack in availability and high costs of RhIG. Other important developments in the past decades have improved the identification, monitoring, and care of pregnancies, fetuses, and neonates with HDFN. Prenatally, fetal anemia may occur and intrauterine transfusions may be needed. Postnatally, pediatricians should be aware of the (antenatally determined) risk of hemolysis in RBC alloimmunization and should provide treatment for hyperbilirubinemia in the early phase and monitor for anemia in the late phase of the disease. Through this review, we aim to provide an overview of important historic events and to provide hands-on guidelines for the delivery and postnatal management of neonates with HDFN. Secondarily, we aim to describe recent scientific findings and evidence gaps. CONCLUSION:  Multiple developments have improved the identification, monitoring, and care of pregnancies and neonates with HDFN throughout the centuries. Pediatricians should be aware of the (antenatally determined) risk of hemolysis in RBC alloimmunization and should provide treatment for hyperbilirubinemia in the early phase and monitor for late anemia in the late phase of the disease. Future studies should be set in an international setting and ultimately aim to eradicate HDFN on a global scale. WHAT IS KNOWN: • Developments have led to a greater understanding of the pathophysiology, an improved serological identification and monitoring of at-risk cases and the current pre- and postnatal treatment. WHAT IS NEW: • This review provides the pediatrician with hands-on guidelines for the delivery and postnatal management of neonates with HDFN. • Future studies should be set in an international setting with the ultimate aim of eradicating HDFN.

A case report on non-D HDFN: Highlighting the role of antibody screening in RhD positive antenatal women.

The widespread use of anti-D immunoglobulin has resulted in a relative increase in the importance of non-D alloimmunization as a cause of hemolytic disease of the fetus and newborn (HDFN). Non-D alloantibodies that are capable of causing severe HDFN include anti-K, anti-E, and anti-c. Anti-c is clinically the most important Rh system antibody after anti-D. Here, we report three cases of neonates presenting with anemia and hyperbilirubinemia with strongly positive direct antiglobulin test who required phototherapy and neonatal exchange transfusion due to non-D antibody in RhD positive antenatal women. Anti-c was common in all the three cases while two cases have one additional non-D antibody. Due to faulty practices, antenatal antibody screening was not done for any case considering the mother's RhD positive status. Hence, antenatal antibody screening should be performed routinely, in all RhD positive pregnant women to reduce the delay in diagnosis and the management of HDFN occurring due to non-D antibodies.

Neonatal outcomes following intrauterine transfusion for hemolytic disease of the fetus and newborn: a twenty-year service review.

OBJECTIVE: The primary objective was to explore perinatal and neonatal outcomes amongst infants who received intrauterine transfusion (IUT) for the management of hemolytic disease of the fetus and newborn (HDFN). The secondary objective was to evaluate the role of key investigations in the fetus at risk of HDFN and assess the relationship with neonatal outcomes. We hypothesized that middle cerebral artery peak systolic velocity (MCA-PSV) and corresponding multiples of the median (MoM) would be predictive of neonatal course. METHODS: This was a retrospective observational study conducted at a tertiary center in the United Kingdom between January 2000 and August 2020. Trust approval was obtained to conduct this service review. Pregnancies requiring IUT for HDFN were identified using the fetal medicine department database. Inclusion criteria were infants who received IUT for HDFN. 67 pregnancies were eligible for inclusion in the study with 156 IUT events. Data were extracted using healthcare records. Statistical analysis was performed using SPSS version 28.0, data were assessed for normality and Spearman's correlation analysis was performed with p values < .05 considered significant. RESULTS: 67 pregnancies were included in the study which led to the live birth of 68 infants (one twin pregnancy). There were no fetal deaths following IUT. There was one neonatal death due to extreme prematurity following spontaneous vaginal delivery at 23 + 4 weeks gestation, occurring three days following IUT. 97% of infants required admission to the neonatal intensive care unit and 88% required phototherapy. 25% of infants required readmission for red blood cell transfusion due to anemia. There was a significant correlation between maternal anti-D antibody levels and length of neonatal admission r = 0.477, p = .014. MCA-PSV and MoM measured prior to the last IUT had a significant positive correlation with the duration of phototherapy: r = 0.527 (p < .001) and r = 0.313 (p < .05) respectively. Linear regression analysis demonstrated a significant positive relationship between MCA-PSV and corresponding MoM recorded prior to the last IUT with r2= 0.177 (p = .003) and r2= 0.101 (p = .029). CONCLUSION: HDFN is an important cause of fetal anemia associated with significant neonatal morbidity. MCA-PSV and MoM may be predictive of neonatal phototherapy requirements. The predictive value of MCA-PSV appears to be dependent on the timing of measurement during the antenatal period and more research is needed. Multicentre collaboration is required to generate a reliable large-scale database to further delineate the value of MCA-PSV and MoM and predict neonatal outcomes in cases of HDFN requiring IUT. This data would assist clinicians in antenatal planning and enable more informed counseling of parents in the antenatal period.

Retrospective analysis of direct antiglobulin test positivity at tertiary academic hospital over 10 years.

BACKGROUND: Hemolytic disease of the fetus and newborn (HDFN) is a clinically significant problem that may potentially affect any pregnancy. Direct antiglobulin test (DAT) is considered to be an important test in identifying newborns who are suspected to have HDN. This study aims in reviewing data regarding a positive DAT result concerning etiology and the development of HDN over a period of 10 years. STUDY DESIGN AND METHODS: A retrospective study of all neonates with a positive DAT result between January 2011 and December 2020 was performed. Data were obtained from patients' electronic hospital files, transfusion medicine databases, and medical birth records. Laboratory parameters along with clinical interventions in neonates with a DAT-positive result and a comparison group of DAT-negative neonates were performed. RESULTS: 36,000 deliveries were registered in this period. 176 (2.65 %) neonates had a positive DAT result. ABO-incompatibility was the most common cause with 59.1 %; Rh incompatibility 13.8 %, minor blood group incompatibility, and other RBC-related antibodies 10.1 %, and unspecified etiology in 17 % of cases. Among DAT-positive cases, 32.7 % of neonates were diagnosed with HDN. ABO-incompatibility was the major reason as well. Initial mean total bilirubin levels were higher in the DAT-positive group than the control group (p < 0.001), and these neonates also had a lower initial hemoglobin level (p < 0.001). The need for therapeutic interventions was significantly higher in DAT-positive neonates (p < 0.001) as 86.8 % underwent phototherapy, with 32.7 %, and 17.6 % receiving exchange transfusion (ET) and intravenous immunoglobulin (IVIG), respectively. CONCLUSION: In conclusion, ABO incompatibility was the most common cause for neonatal DAT positivity. Besides the common causes of DAT positivity, there would be rare but important conditions that may lead to a positive result, such as antibodies passively acquired from mothers in the context of alloimmunizations or using drugs. In addition, as a high rate of therapeutic intervention was identified among neonates with a DAT-positive result, there is a crucial need for increasing awareness regarding early diagnosis of the condition, careful monitoring, and the employment of prenatal alloimmunization screening tests.

The combined effect of anti-D and non-D Rh antibodies in maternal alloimmunization

Objective: This study aims to investigate the distribution of antibodies that cause hemolytic disease of the fetus and newborn (HDFN) and compare the clinical outcomes of pregnancies affected by anti-D and anti-D combined with non-D Rh alloimmunization. Materials and Methods: We retrospectively searched and obtained the perinatal and neonatal data of patients with anti-D antibodies and anti-D combined with non-D Rh antibodies (anti-c, -C, -e, -E, and -Kell) from October 2015 to December 2018 at the University of Health Sciences Turkey, Kanuni Sultan Süleyman Training and Research Hospital. Univariate and multiple logistic regression analyses and adjusted odds ratios with their confidence intervals were used to define independent risk factors for non-D antibody positive. Results: The severe fetal hydrops rate was significantly higher in the anti-D combined non-D group (3/25, 12%) than in the anti-D group (1/128, 0.08%, p<0.001). The intrauterine transfusion (IUT) requirement in the anti-D combined non-D group (16/25, 64%) tended to be significantly higher than that in the anti-D group (5/128, 7.46%, p<0.001). The incidence of neonatal exchange transfusion, top-up transfusion, and postnatal phototherapy frequency in the anti-D combined non-D group was significantly higher than in the anti-D group. Conclusion: Anti-D combined with another non-D Rh alloantibody resulted in significantly higher HDFN rates than the anti-D alloimmunized pregnancies. Also, anti-D in association with non-D Rh antibodies resulted in more severe HDFN requiring more invasive treatment procedures, including IUT, neonatal exchange transfusion, or top-up transfusion.

Management and clinical consequences of red blood cell antibodies in pregnancy: A population-based cohort study.

INTRODUCTION: Anti-D alloimmunization is the most common cause of severe hemolytic disease of the fetus and newborn (HDFN). The management of pregnancies affected by less frequent red blood cell (RBC) antibodies poses a challenge to clinicians, and perinatal outcomes are less well described. This study aimed to describe the frequency of clinically significant RBC antibodies in our pregnant population and analyze the risk of prenatal and postnatal treatment for HDFN in relation to our national risk classification system and management guidelines. MATERIAL AND METHODS: A retrospective cohort study in the population of all alloimmunized singleton pregnancies in the Stockholm region 1990-2016. Descriptive summaries of different RBC antibodies and pregnancy outcomes were presented, the risks of intrauterine blood transfusion (IUT) and neonatal treatment for HDFN were estimated by type of antibodies. RESULTS: Of the 1724 alloimmunized pregnancies, 1079 (63%) were at risk of HDFN and constituted our study cohort. Anti-D was detected in 492 (46%) pregnancies, followed by anti-E in 161 (15%), and anti-c in 128 (12%). Eighty-seven (8%) pregnancies had IUT, with the highest risk in pregnancies affected by anti-D combined with other antibodies. The maximum titer recorded before IUT was 64 or above, except for two pregnancies affected by anti-c, for which the maximum titers were 8 and 16. For the 942 (95%) live-born neonates from 992 alloimmunized pregnancies without IUT, the median gestational age at birth was 38+5  weeks compared with 35+5  weeks for those who had IUT. Neonatal treatment was most common in the anti-D alone and anti-D combined groups, with 136 (57%) and 21 (44%), respectively, treated with phototherapy and 35 (15%) and 9 (20%) receiving exchange transfusions, respectively. For pregnancies complicated by moderate- and low-risk antibodies, phototherapy was less frequent (32 [36%] and 21 [19%]) and exchange transfusion was rare (5 [6%] and 3 [3%]). CONCLUSIONS: Anti-D, especially in combination with other antibodies, presents the highest risk of severe HDFN. The classification of less frequent and less well-known RBC antibodies into risk groups can help clinicians in assessing the risk of HDFN and counseling alloimmunized pregnant women regarding the risk of prenatal and postnatal treatments.

Implementation of a Standardized Prenatal Testing Protocol in an Integrated, Multihospital Health System.

OBJECTIVES: When our institution grew into an integrated multihospital health system, we were faced with the need to standardize laboratory processes, including blood bank processes, across all locations. The purpose of this article is to describe our experience of standardizing the protocols for prenatal testing. METHODS: For each hospital in the system, we established service tiers to define tests offered on site or referred to another location. For each prenatal test, we examined the related processes for ways to improve uniformity, efficiency, and reliability. Throughout this process of standardization, we collaborated with the clinical services to gain concurrence on the interpretation and reporting of results. RESULTS: We created and implemented a uniform protocol for testing prenatal patients. The protocol standardized the definition of critical titer, instituted criteria to identify passively acquired anti-D, and established a process for the follow-up of women with inconsistent serologic results on Rh(D) typing. CONCLUSIONS: Close collaboration with the clinical services ensured that our testing protocol is aligned with the needs of the integrated obstetrics service in the health system. The approach described in this article may provide a plan outline for pathologists facing similar challenges at other integrated health systems.

Hemolytic Disease of the Fetus and Newborn Caused by Maternal Autoantibody with Mimicking Anti-E Specificity.

OBJECTIVE: There are few reports of hemolytic disease of the fetus and newborn (HDFN) caused by maternal autoantibodies. METHODS: We describe the case of a pregnant patient aged 26 years with systemic lupus erythematosus without any transfusion history who developed autoantibody with mimicking anti-E specificity. Her newborn developed HDFN caused by the maternal autoantibody. RESULTS: The clinical symptoms of the newborn were not serious. After bilirubin light phototherapy and other symptomatic supportive treatment, the baby was discharged with a good prognosis. CONCLUSION: This is the first reported case of HDFN caused by maternal autoantibody with mimicking anti-E specificity. However, the real antigenic target of the autoantibody was not clear.

Hemolytic disease of the fetus and newborn due to multiple alloantibodies in pregnancy.

Immune hemolytic disease of the fetus and newborn is a condition in which there is the premature destruction of fetal or neonatal red cells due to maternal alloantibody against red cell antigen inherited from father. We report the case of Hemolytic disease of fetus and newborn (HDFN) due to anti-E and anti-Fya antibody. Blood grouping was done using the conventional tube technique. Rh and Kell phenotyping of the patient and her husband performed by column agglutination and Duffy phenotyping were done by the conventional tube technique. Direct antiglobulin test was performed by column agglutination technique. Antibody screening and identification were done. Anti-E and Anti-Fya were identified with titer of Anti-E: 1:64 and Anti-Fya: 1:256. The patient's neonate developed jaundice. Phototherapy was given. Bilirubin stabilized and discharged on the 12th day.

A case of mild HDFN caused by anti-C, anti-D, and anti-G: Diagnostic strategy and clinical significance of distinguishing anti-G from anti-D and anti-C.

Anti-G is commonly present with anti-D and anti-C and can confuse serological investigations. The differentiation of anti-G from anti-D and anti-C is particularly essential for the accurate diagnosis of hemolytic disease of the fetus and newborn (HDFN) and appropriate administration of anti-D immunoglobulin prophylaxis in Rhesus (Rh) negative women. We reported a rare case of anti-G together with anti-D and anti-C in a pregnant woman and her female neonate. The titers of IgG anti-D, anti-C, and anti-G in the woman were 256, 128, and 32, respectively. While the titers of IgG anti-D, anti-C, and anti-G in the neonate were 16, 8, and 4, respectively. The neonate experienced mild HDFN and only received phototherapy during hospitalization. This report discusses the diagnostic strategy and clinical significance of differentiating anti-G from anti-D and anti-C.

Anemic Disease of the Newborn With Little Increase in Hemolysis and Erythropoiesis Due to Maternal Anti-Jra: A Case Study and Review of the Literature.

The severity of the hemolytic disease of the fetus and newborn (HDFN) due to Jra mismatch ranges from no symptoms to severe anemia that requires intrauterine and exchange transfusions. We encountered a newborn, born to a healthy mother having anti-Jra at 38 weeks of pregnancy, who had moderate anemia, a positive direct antiglobulin test (DAT) result, no increased erythropoiesis, and no jaundice at birth. Flow cytometry revealed that the Jra antigen of red cells in the infant was nearly negative at birth, biphasic at 5 weeks, and lowly expressed at 7 months of life. We searched online for previous case reports on HDFN due to Jra incompatibility. Among 63 reported cases, excluding 25 cases, 38 were included with the present case for analysis. Of 39 newborns, 10 developed clear anemia (hemoglobin <10.0 g/dL), and 1 died, 5 developed hydrops fetalis, 4 needed intrauterine transfusion and/or exchange transfusion, and 3 received red cell transfusion after birth; overlaps were included. Among 29 neonates with no anemia, 8 needed interventions including phototherapy and γ-globulin infusion, and the remaining 21 received conservative supports only. The maternal anti-Jra titer, ranging between 4 and 2048, did not correlate with the severity of anemia, levels of bilirubin, or any interventions required. The DAT of red cells was positive in 29 of 36 fetuses/newborns tested, whereas it was often negative among anemic neonates (4 of 9) (P < .05). Hematopoiesis did not increase effectively, as indicated by reticulocyte ratios between 1.7% and 22.3%, even with the increase in reticulocytes in anemic neonates compared with nonanemic neonates (P < .05). Total bilirubin levels ranged broadly between 0.2 and 14.3 mg/dL but were generally low. The maternal anti-Jra titer and IgG3 subclass did not correlate with the morbidity of the newborns. Being identical/compatible between mothers and their infants may possibly enhance infants' morbidity, as a weak tendency was observed (P = .053). Maternal anti-Jra may suppress erythropoiesis in fetuses via a mechanism different from the established HDFN, such as anti-D, as evidenced by the lower reticulocyte count and small increase in bilirubin in neonates. As the anti-Jra titer, IgG subclass, and DAT were not correlated with the severity, the mechanism of anti-Jra-induced HDFN remains to be elucidated.

Molecular characterization and multidisciplinary management of Gerbich hemolytic disease of the newborn.

Gerbich (Ge) antigens are high frequency red cell antigens expressed on glycophorin C (GYPC) and glycophorin D. Hemolytic disease of the fetus and newborn (HDFN) due to Gerbich antibody is rare and presents a clinical challenge, as Gerbich negative blood is scarce. We report a case of HDFN due to maternal Ge3 negative phenotype and anti-Ge3 alloimmunization, successfully managed by transfusion of maternal blood. Molecular testing revealed that the mother has homozygous deletion of exon 3 of GYPC, the father is homozygous wildtype for GYPC, and the infant is obligate heterozygote expressing Ge3.

Anti-M Alloimmunization: Management and Outcome at a Single Institution.

Objective The objective of this study was to review the management strategies and outcomes in gravidas with anti-M alloimmunization over 15 years. Study Design Data collected from 195 pregnant patients with anti-M antibodies from July 2000 through June 2016 were reviewed retrospectively. We analyzed indirect antiglobulin test titer results, paternal or fetal/neonatal M antigen status, antepartum course, and perinatal outcomes. Results Anti-M antibodies were found in 146 women and 195pregnancies. Among those with positive indirect antiglobulin tests, 193 pregnancies had titers at or below 1:4. Only one patient with an initial low titer experienced a more than twofold increase to a titer 1:64. Two women underwent an amniocentesis and cordocentesis. Ninety-five (73.6%) of the 129 infants tested were positive for the M antigen. Nine infants required phototherapy. There were no cases of hemolytic disease of the fetus or newborn, mild or severe. Conclusion The incidence of severe hemolytic disease of the newborn due to anti-M is extremely low. We found no cases in our review of 195 pregnancies, despite several cases of severe hemolytic disease of the newborn reported in the literature. We have created an algorithm for the management of anti-M antibodies in pregnancy based on our data and extensive literature review.

Targeted antenatal anti-D prophylaxis program for RhD-negative pregnant women - outcome of the first two years of a national program in Finland.

INTRODUCTION: The aim of this study was to assess the accuracy of the non-invasive fetal RHD test at 24-26 weeks of gestation as part of the national antenatal screening program to target routine antenatal anti-D prophylaxis (RAADP) at 28-30 weeks at women carrying an RhD-positive fetus. MATERIAL AND METHODS: A prospective cohort study involving all maternity care centers and delivery hospitals in Finland between February 2014 and January 2016. Fetal RHD genotyping using cell-free fetal DNA in maternal plasma was performed with real-time polymerase chain reaction in a centralized setting. The results were systematically compared with the serological newborn RhD typing. The main outcome measure was the accuracy of the fetal RHD assay; the secondary variable was compliance with the newly introduced RAADP program. RESULTS: Fetal RHD was screened from 10 814 women. For the detection of fetal RHD, sensitivity was 99.99% [95% confidence interval (CI) 99.92-99.99] and specificity 99.81% (95% CI 99.60-99.92). One false-negative and seven false-positive results were reported by the delivery hospitals in two years. The negative predictive value of the test was 99.97% (95% CI 99.81-99.99). At the end of the study period, over 98% of the RhD-negative women participated in the new screening program. CONCLUSIONS: The targeted RAAPD program was implemented effectively in the national maternity care program in Finland. An accurate fetal RHD screening test allows discontinuation of newborn testing without risking the postnatal prophylaxis program. In the future, the main area to investigate will be the clinical effect of RAADP on subsequent pregnancies.

Neonatal management and outcome in alloimmune hemolytic disease.

INTRODUCTION: Hemolytic disease of the fetus and newborn (HDFN) occurs when fetal and neonatal erythroid cells are destroyed by maternal erythrocyte alloantibodies, it leads to anemia and hydrops in the fetus, and hyperbilirubinemia and kernicterus in the newborn. Postnatal care consists of intensive phototherapy and exchange transfusions to treat severe hyperbilirubinemia and top-up transfusions to treat early and late anemia. Other postnatal complications have been reported such as thrombocytopenia, iron overload and cholestasis requiring specific management. Areas covered: This review focusses on the current neonatal management and outcome of hemolytic disease and discusses postnatal treatment options as well as literature on long-term neurodevelopmental outcome. Expert commentary: Despite major advances in neonatal management, multiple issues have to be addressed to optimize postnatal management and completely eradicate kernicterus. Except for strict adherence to guidelines, improvement could be achieved by clarifying the epidemiology and pathophysiology of HDFN. Several pharmacotherapeutic agents should be further researched as alternative treatment options in hyperbilirubinemia, including immunoglobulins, albumin, phenobarbital, metalloporphyrins, zinc, clofibrate and prebiotics. Larger trials are warranted to evaluate EPO, folate and vitamin E in neonates. Long-term follow-up studies are needed in HDFN, especially on thrombocytopenia, iron overload and cholestasis.

Clinical Significance of an Alloantibody against the Kell Blood Group Glycoprotein.

BACKGROUND: Kell null (K0) individuals can produce anti-Ku, an antibody against many epitopes in the Kell glycoprotein, after transfusion and/or pregnancy. Since sensitized K0 patients are rare, little is known about anti-Ku clinical relevance and in particular about its association to hemolytic disease of the fetus and newborn. CASE REPORT: This work describes a case of neonatal hyperbilirubinemia due to immune-mediated erythrocyte destruction by an alloantibody directed against the Kell glycoprotein. Serologic and molecular approaches identified an anti-Ku alloantibody in maternal serum. A homozygous IVS3 + 1g>a point mutation (KEL*02N.06 allele) was found to be responsible for the lack of Kell antigen expression in the mother's red blood cell and subsequent alloimmunization after a previous pregnancy. Even though in most cases Kell antibodies are clinically severe and may cause suppression of erythropoiesis, in our case the newborn had a moderate anemia and hyperbilirubinemia that was successfully treated with phototherapy without requiring exchange transfusion. Serological and molecular studies performed in the proband's family members allowed us to provide them with proper counseling regarding alloimmunization after transfusion and/or pregnancy. CONCLUSIONS: This case enlarges the understanding of the clinical significance of alloantibodies against Kell blood group antigens.