Intrauterine blood transfusion: current indications and associated risks

'Old is gold' does conventional test tube method still reign supreme? An immuno-haematological survey of anti-D detection and titration in ante-natal cases among major hospitals across India

INTRODUCTION

Anti-D detection and titration plays a major role in RhD negative antenatal cases both, for monitoring maternal as well as fetal status as well as initiation of early therapeutic interventions, such as intra-uterine transfusions (IUT) to improve maternal as well as fetal morbidity and mortality and reduce the adverse effects of haemolytic disease of fetus and newborn (HDFN). We conducted a survey focusing on the policies and procedures of anti-D detection and titration among major tertiary care centres across India.

METHODOLOGY

The survey was drafted by a working group of transfusion medicine and immunohematology specialists from six different centres in India. Data were obtained via the use of an online questionnaire.

RESULTS

Results were categorised into four categories, Hospital information, immuno-haematological testing methodology, clinical significance of anti-D testing and the role of transfusion medicine specialists. The survey highlighted the modalities as well as the methodologies of anti-D detection and titration in antenatal women across different major tertiary care centres in India.

CONCLUSION

This survey provided a unique snapshot of the prevalent methodologies being employed by major tertiary care centres across the country for detection and titration of anti-D levels as well as the important role it plays in the therapy of affected antenatal women to minimise adverse effects on the fetus.

Maternal isoimmunization associated fetal anemia: A case report

Maternal isoimmunization occurs when a pregnant woman develops an immune reaction due to the inheritance of a red-cell antigen, which is paternally derived and can result in fetal anemia, hemolysis, fetal death, and hydrops fetalis as the antibodies might travel through the placenta and get adhered to the antigens present in the erythrocytes of the fetus. This report highlights a rare case of Rh isoimmunization leading to fetal anemia in a 26-year-old female and evaluates the impact of intrauterine transfusion (IUT) in terms of the gestational age at delivery along with the mode of delivery, procedural complications, and overall survival rate of the fetus. In conclusion, the most frequent cause of fetal anemia is Rh alloimmunization, which should be taken into consideration while making a differential diagnosis throughout the assessment. Improvements in IUT procedures and earlier detection of the MCA-PSV by Doppler ultrasonographic examination have also contributed to better results.

Incidence and Risk Factors of Cholestasis in Newborns with Hemolytic Disease-A Case-Control Study

Background/Objectives: One of the rare causes of cholestasis may be hemolytic disease of the fetus and newborn (HDFN). Methods: We retrospectively analyzed 88 medical records of HDFN newborns with cholestasis and 186 records of children with HDFN without cholestasis and conducted an observational, case-control, retrospective study. Results: Factors influencing the risk of cholestasis were lower gestational age at birth (36.83 ± 1.9 vs. 37.57 ± 1.8, p = 0.002), Rh or Kidd HDFN (80.7% vs. 53.2%), and the need for intrauterine transfusion (27.3 vs. 11.8%). The subjects had lower hemoglobin concentrations at birth (14.01 ± 3.8 vs. 16.39 ± 2.8 g/dL) and during whole hospital stay, higher cord blood total bilirubin concentration (4.26 ± 1.8 vs. 2.39 ± 1.4 mg/dL), higher maximum bilirubin concentration (15.27 ± 5.8 vs. 10.24 ± 3.4 mg/dL), and more frequent liver ultrasound abnormalities (19.9 vs. 6.3%). They also required more extended hospitalization due to higher rates of postnatal blood transfusion (33 vs. 3.8%), more frequent need for exchange transfusion (8.8% vs. 2.2%), more extended time and higher risk of phototherapy (94.3 vs. 59.1%), and higher usage of immunoglobulins (55.7 vs. 8.1%), parenteral nutrition (45.5 vs. 12.9%), and antibiotics (14.8 vs. 4.8%). Conclusions: The risk factors for cholestasis in children with HDFN are lower gestational age at delivery, Rh and Kidd serological type of HDFN, and the need for intrauterine transfusions.

Effect of Anti-D titers in RhD-negative pregnant women on fetuses and newborns: A retrospective study

BACKGROUND

Transplacental-derived anti-D IgG in RhD-negative pregnant women can trigger an immune response to Rh D-positive red cells in fetuses and newborns. We assessed the effect of anti-D titers in RhD-negative pregnant women on fetuses and newborns.

METHODS

The clinical data of 142 singleton RhD-sensitized pregnancies were retrospectively collected. The pregnant women received routine prenatal care and the newborns had standard care. Based on the tertile categories of the pregnancies, the maximum titers of anti-D IgG in the pregnant women were divided into three groups ranging from low to high as follows: low-titer group (anti-D titer: 1:4-1:128, n = 57); medium-titer group (anti-D titer: 1:256-1:512, n = 50); and high-titer group (anti-D titer: 1:1024-1:4096, n = 35).

RESULTS

The frequencies of major neonatal complications did not significantly differ among the three groups. The high-titer group had the highest frequency of pregnancies requiring intrauterine transfusion (IUT) and number of IUTs among the three groups. The high-titer group had a significantly higher frequency of newborns treated with top-up transfusion, number of top-up transfusions, frequency of newborns treated with exchange transfusion (ET), and number of ETs when compared to the low-titer group.

CONCLUSION

Higher anti-D titers in RhD-negative pregnant women predict more severe fetal and neonatal hemolytic anemia. Increasing maternal anti-D titers results in an increased need for IUTs, and neonatal top-up transfusions and ETs. Methods for reducing titers of anti-D IgG in RhD-sensitized pregnant women warrants further investigation.

Intravenous immunoglobulin for the treatment of severe maternal alloimmunization: individual patient data meta-analysis

OBJECTIVE

This study aimed to investigate the outcomes associated with the administration of maternal intravenous immunoglobulin in high-risk red blood cell-alloimmunized pregnancies.

DATA SOURCES

Medline, Embase, and Cochrane Library were systematically searched until June 2023.

STUDY ELIGIBILITY CRITERIA

This review included studies reporting on pregnancies with severe red blood cell alloimmunization, defined as either a previous fetal or neonatal death or the need for intrauterine transfusion before 24 weeks of gestation in the previous pregnancy as a result of hemolytic disease of the fetus and newborn.

METHODS

Cases were pregnancies that received intravenous immunoglobulin, whereas controls did not. Individual patient data meta-analysis was performed using the Bayesian framework.

RESULTS

Individual patient data analysis included 8 studies consisting of 97 cases and 97 controls. Intravenous immunoglobulin was associated with prolonged delta gestational age at the first intrauterine transfusion (gestational age of current pregnancy - gestational age at previous pregnancy) (mean difference, 3.19 weeks; 95% credible interval, 1.28-5.05), prolonged gestational age at the first intrauterine transfusion (mean difference, 1.32 weeks; 95% credible interval, 0.08-2.50), reduced risk of fetal hydrops at the time of first intrauterine transfusion (incidence rate ratio, 0.19; 95% credible interval, 0.07-0.45), reduced risk of fetal demise (incidence rate ratio, 0.23; 95% credible interval, 0.10-0.47), higher chances of live birth at ≥28 weeks (incidence rate ratio, 1.88; 95% credible interval, 1.31-2.69;), higher chances of live birth at ≥32 weeks (incidence rate ratio, 1.93; 95% credible interval, 1.32-2.83), and higher chances of survival at birth (incidence rate ratio, 1.82; 95% credible interval, 1.30-2.61). There was no substantial difference in the number of intrauterine transfusions, hemoglobin level at birth, bilirubin level at birth, or survival at hospital discharge for live births.

CONCLUSION

Intravenous immunoglobulin treatment in pregnancies at risk of severe early hemolytic disease of the fetus and newborn seems to have a clinically relevant beneficial effect on the course and severity of the disease.

Double-Filtration Plasmapheresis and High-Dose Intravenous Immunoglobulin Therapy in a Case of Anti-M Alloimmunization

Hemolytic disease is a common cause of fetal morbidity and mortality. The anti-M blood cell alloantibodies are one of the most severe causes of fetal anemia and intrauterine death. Since no standard treatment method has been established for pregnant women, the management of this pathology is through conventional methods used for treating Rh blood-type alloimmunization. For the first time, we report a unique case wherein a pregnant woman who had intrauterine fetal death in two previous pregnancies with very low titers of anti-M antibodies had negative effects during very early pregnancy, which were successfully managed in her third pregnancy with a novel protocol. We aggressively managed the blood type (anti-M antibody) and blood platelet incompatibilities (anti-HPA-4b antibody) through combination therapy twice a week (46 cycles between 12 and 34 weeks) of double filtration plasmapheresis (DFPP) and high-dose γ-globulin (20-40 g/wk). An elective cesarean section was performed at 34 weeks, and a healthy neonate was born without detection of alloantibodies in the umbilical cord blood. Our report suggests that the combination of DFPP and intravenous immunoglobulin should be considered for the treatment of anti-M alloimmunization in pregnant women.

First intrauterine transfusion in Rh isoimmunised triplet pregnancy

G3P2L1, 28+4 weeks of gestation rhesus (Rh) isoimmunised pregnant women, was referred with trichorionic triamniotic triplet pregnancy with Rh antibody titres of 1:32. Nuchal translucency and anomaly scan were within normal limits with no major malformation for any of the fetuses. Obstetric colour Doppler with middle cerebral artery peak systolic volume revealed foetal anaemia in all three fetuses having velocities corresponding to around 1.5 times the median. Decision of intrauterine transfusion of blood to all three fetuses was taken. Access to fetuses was challenging and expertise in interventional ultrasound was required for transfusion. The patient tolerated the procedure well and eventually went on to deliver uneventfully at 34 weeks of gestation for worsening pre-eclampsia. After birth, all three triplets received triple-surface intensive phototherapy and intravenous immunoglobulin at a dosage of 1 g/kg. Phototherapy was gradually reduced and discontinued within 72 hours, and the infants were discharged from the neonatal intensive care unit at 96 hours of age.

The selection and preparation of red cell components for intrauterine transfusion: A national survey

BACKGROUND AND OBJECTIVES

The practice regarding the selection and preparation of red blood cells (RBCs) for intrauterine transfusion (IUT) is variable reflecting historical practice and expert opinion rather than evidence-based recommendations. The aim of this survey was to assess Canadian hospital blood bank practice with respect to red cell IUT.

MATERIALS AND METHODS

A survey was sent to nine hospital laboratories known to perform red cell IUT. Questions regarding component selection, processing, foetal pre-transfusion testing, transfusion administration, documentation and traceability were assessed.

RESULTS

The median annual number of IUTs performed in Canada was 109 (interquartile range, 103-118). RBC selection criteria included allogeneic, Cytomegalovirus seronegative, irradiated, fresh units with most sites preferentially providing HbS negative, group O, RhD negative, Kell negative and units lacking the corresponding maternal antibody without extended matching to the maternal phenotype. Red cell processing varied with respect to target haematocrit, use of saline reconstitution (n = 4), use of an automated procedure for red cell concentration (n = 1) and incorporation of a wash step (n = 2). Foetal pre-transfusion testing uniformly included haemoglobin measurement, but additional serologic testing varied. A variety of strategies were used to link the IUT event to the neonate post-delivery, including the creation of a unique foetal blood bank identifier at three sites.

CONCLUSION

This survey reviews current practice and highlights the need for standardized national guidelines regarding the selection and preparation of RBCs for IUT. This study has prompted a re-examination of priorities for RBC selection for IUT and highlighted strategies for transfusion traceability in this unique setting.

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.

Liver Dysfunction with Severe Cholestasis and Coagulation Disorders in the Course of Hemolytic Disease of the Newborn Requiring Chelation Therapy-A Case Report and Review of the Literature

Severe hemolytic disease of the fetus and newborn (HDFN) requiring intrauterine transfusions (IUTs) may cause iron accumulation, resulting in liver damage, which may lead to cholestasis and coagulation disorders. In this article, we reported a case of a female neonate who underwent chelation therapy with a positive outcome, and we reviewed the English and Polish literature on chelation therapy in HDFN available in PubMed. The patient with maximum ferritin concentration above 33,511.2 ng/mL developed liver dysfunction with coagulation disorders requiring multiple transfusions of fresh frozen plasma (FFP), Octaplex® and cryoprecipitate, and hypoalbuminemia treated with numerous albumin infusions. Furthermore, severe cholestasis was observed with direct bilirubin levels up to 33.14 mg/dL. Additionally, the child developed transient myelosuppression with neutropenia, thrombocytopenia, and low reticulocyte count due to several blood transfusions. The differential diagnosis tests were conducted to rule out any causes of hepatic failure other than hemolytic disease of the newborn. This case proves that adequate treatment of severe HDFN with anemia requiring IUT and hepatic failure can lead to positive outcomes with no long-term consequences.

Massive fetomaternal hemorrhage in a monochorionic-diamniotic twin pregnancy: a case report

Fetomaternal hemorrhage (FMH) result into severe, life-threatening fetal anemia and cause intrauterine death of the fetus. It is tough for an early diagnosis of FMH before pregnancy and few authors reported FMH in a twin pregnancy. Therefore, we reported a case of massive FMH. The patient felt a decrease in fetal movements at 33⁺⁵ gestational weeks. Cardiotocography showed sinusoidal heart rate patterns in one fetus. The fetal hemoglobin level in maternal blood was 6.4% (normal range for single pregnancy, 0.0%-2.0%). Since the patient was diagnosed with fetal distress, cesarean section was performed and both babies delivered to receive neonatal treatment. Severe anemia was apparent in both neonates, based on red blood cell count, hemoglobin concentration, and hematocrit of 0.75 × 10¹²/L and 0.61 × 10¹²/L, 2.8 g/dL and 2.4 g/dL, and 10.0% and 8.4%, respectively. The neonates were admitted to the intensive care unit for prematurity care and presently are well. In our experience, an early diagnosis of FMH contributed to saving fetus. Obstetricians should highlight fetal movements counting to every patient. Once massive FMH occurs in monochorionic twins, both fetuses may develop severe anemia and require emergency intervention.

Management of large placental chorioangioma: two-port laser approach for fetal intervention

OBJECTIVES

There is a paucity of literature providing evidence-based guidelines for the management of large placental chorioangioma (≥ 4 cm in diameter). The objectives of this study were to compare outcomes between patients managed expectantly and those undergoing in-utero intervention and to describe the different in-utero techniques used for cessation of blood flow to the tumor and the associated outcome.

METHODS

This was a retrospective cohort study of 34 patients referred for the management of large placental chorioangioma in a single center between January 2011 and December 2022, who were managed expectantly or underwent in-utero intervention. In-utero intervention was performed when the fetus developed any signs of impending compromise, including high combined cardiac output (CCO), worsening polyhydramnios or abnormal fetal Doppler velocimetry findings. Interventions included radiofrequency ablation (RFA), interstitial laser ablation (ILA) and single-port or two-port fetoscopic laser photocoagulation (FLP). Treatment selection was dependent on the proximity of the tumor to the umbilical cord insertion (UCI) and placental location. The two-port technique was performed in patients with a chorioangioma with large feeding vessels (≥ 3 mm) located in the posterior placenta, in which one port was used for occlusion using bipolar forceps and the other port was used for laser photocoagulation of the feeding vessels downstream. The single-port technique was used for chorioangioma with small feeding vessels (< 3 mm) located in the posterior placenta. ILA or RFA was performed in cases with an anterior placenta. Supportive treatments, including amnioreduction and intrauterine transfusion (IUT), were performed for worsening polyhydramnios and suspected fetal anemia based on middle cerebral artery Doppler flow studies, respectively. Comparative statistical analysis between cases undergoing expectant management vs in-utero intervention was performed. Descriptive details were provided for patients who underwent in-utero intervention.

RESULTS

Thirty-four cases of large chorioangioma were evaluated, of which 25 (73.5%) were managed expectantly and nine (26.5%) underwent intervention. The frequency of polyhydramnios was significantly higher in the intervention group compared with the expectant-management group (66.7% vs 8.0%, P < 0.001). The live-birth rate among expectantly managed cases with large chorioangioma was significantly higher compared with that in cases that underwent in-utero intervention (96.0% vs 62.5%, P = 0.01). In the intervention group, preoperative CCO was elevated in all cases with available information and preoperative hydrops was present in 33.3% (3/9) of cases. One patient experienced fetal demise following IUT prior to planned FLP. Among the remaining eight patients, four underwent two-port FLP, two underwent single-port FLP, one underwent ILA and one underwent both ILA and RFA. All three cases in which hydrops was present at the time of intervention resulted in fetal demise.

CONCLUSIONS

In-utero interventions aimed at cessation of blood flow in the feeding vessels are a therapeutic option for the management of cases with large chorioangioma. The two-port percutaneous technique appears to improve the efficiency of FLP when a large chorioangioma with large feeding vessels is located in the posterior placenta. We propose that in-utero interventions for large chorioangioma should be initiated prior to the development of fetal hydrops. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Maternal and fetal safety outcomes after in utero stem cell injection: A systematic review

OBJECTIVE

To investigate the maternal and fetal safety of In utero stem cell transplantation (IUSCT).

METHODS

Medline®, Embase and Cochrane library (1967-2023) search for publications reporting IUSCT in humans. Two reviewers independently screened abstracts and full-text papers.

RESULTS

Sixty six transplantation procedures in 52 fetuses were performed for haemoglobinopathies (n = 14), red cell/bleeding disorders (n = 4), immunodeficiencies (n = 15), storage disorders (n = 7), osteogenesis imperfecta (n = 2) and healthy fetuses (n = 10). The average gestational age was 18.9 weeks; of procedures reporting the injection route, cells were delivered by intraperitoneal (n = 37), intravenous (n = 19), or intracardiac (n = 4) injection or a combination (n = 3); most fetuses received one injection (n = 41). Haematopoietic (n = 40) or mesenchymal (n = 12) stem cells were delivered. The cell dose was inconsistently reported (range 1.8-3.3 × 109 cells total (n = 27); 2.7-5.0 × 109 /kg estimated fetal weight (n = 17)). The acute fetal procedural complication rate was 4.5% (3/66); the acute fetal mortality rate was 3.0% (2/66). Neonatal survival was 69.2% (36/52). Immediate maternal and pregnancy outcomes were reported in only 30.8% (16/52) and 44.2% (23/52) of cases respectively. Four fetal/pregnancy outcomes would also classify as ≥ Grade 2 maternal adverse events.

CONCLUSIONS

Short-, medium-, and long-term maternal and fetal adverse events should be reported in all IUSCT studies.

Accuracy of a portable hemoglobinometer (HemoCue) to measure fetal hemoglobin values during in utero transfusion

OBJECTIVES

The current recommended treatment for severe fetal anemia is in utero transfusion (IUT). During this procedure, the evaluation of the necessary volume of transfused blood is based on regular measurement of fetal hemoglobin (FHb) concentration. The gold standard measurement is performed in the biology laboratory. A rapid medical test such as HemoCue® is an effective way to predict FHb concentration. It would reduce the time to obtain results and therefore the procedure duration. To evaluate the accuracy of HemoCue® to measure FHb during IUT, we compared Hb levels obtained by HemoCue® and by our biology laboratory.

METHODS

This retrospective study involved all pregnant women who had undergone an IUT in the university hospital of Clermont-Ferrand, France, during the period from 1 January 2010 to 6 June 2021. The FHb level was evaluated by two methods, a rapid medical test, HemoCue®, and a standard method in the biology laboratory.

RESULTS

We obtained 244 pairs of results from HemoCue® and our laboratory, of 90 IUT procedures. The correlation between the two sets of results was excellent, with Lin's concordance correlation coefficient of 0.979. However, we established that the measurements were not significantly modified by IUT number, puncture time, cause of fetal anemia, estimated fetal weight, gestational age, and delay between two IUT or middle cerebral artery peak systolic velocity values.

CONCLUSION

Our results allowed to extend the relevance of FHb measurements by HemoCue® during IUT.

How do we perform intrauterine transfusions?

BACKGROUND

Intrauterine transfusion (IUT) is an invasive but critical and potentially life-saving intervention for severe fetal anemia with demonstrated improvement in outcomes. The fetus is vulnerable to hemodynamic alterations and transfusion-related adverse events; therefore, special consideration must be given to blood component selection and modification. There is widespread IUT practice variability, and existing guidance primarily relies on expert opinion and single center experiences.

STUDY DESIGN AND METHODS

Experts in Maternal Fetal Medicine, Pediatric Hematology, and Transfusion Medicine from centers across the United States, collectively performing about 120 IUT annually, offer a multidisciplinary perspective on the performance of IUT and preparation of blood components. This perspective includes strategies for identifying an at-risk fetus, communicating between disciplines, determining the necessary blood volume, selecting and processing blood components, documenting the procedure in medical record, and managing the neonate.

RESULTS

Identifying an at-risk fetus relies on review of the clinical history, non-invasive monitoring, and laboratory evaluation. We recommend the use of relatively fresh, group O, cytomegalovirus-safe, freshly irradiated, red blood cells (RBC) that are Hemoglobin S negative and antigen-negative for any maternal antibody, if indicated. These RBC units should be concentrated to remove additives and increase the hematocrit thus minimizing fluctuations in fetal volume status. The units intended for IUT should be labeled clearly and the documentation of transfusion differentiated in the maternal medical record.

DISCUSSION

An awareness of the technical, logistical, and regulatory considerations for IUT performance will facilitate improved communication and patient care, especially when rare units of RBC are required.

Intrauterine enzyme replacement therapies for lysosomal storage disorders: Current developments and promising future prospects

Lysosomal storage disorders (LSDs) are a group of monogenic condition, with many characterized by an enzyme deficiency leading to the accumulation of an undegraded substrate within the lysosomes. For those LSDs, postnatal enzyme replacement therapy (ERT) represents the standard of care, but this treatment has limitations when administered only postnatally because, at that point, prenatal disease sequelae may be irreversible. Furthermore, most forms of ERT, specifically those administered systemically, are currently unable to access certain tissues, such as the central nervous system (CNS), and furthermore, may initiate an immune response. In utero enzyme replacement therapy (IUERT) is a novel approach to address these challenges evaluated in a first-in-human clinical trial for IUERT in LSDs (NCT04532047). IUERT has numerous advantages: in-utero intervention may prevent early pathology; the CNS can be accessed before the blood-brain barrier forms; and the unique fetal immune system enables exposure to new proteins with the potential to prevent an immune response and may induce sustained tolerance. However, there are challenges and limitations for any fetal procedure that involves two patients. This article reviews the current state of IUERT for LSDs, including its advantages, limitations, and potential future directions for definitive therapies.

Double/Triple Intrauterine Blood Transfusion in Rh-isoimmunized Anemic Fetuses in Multiple Pregnancies with Favorable Outcome

Background

Multiple pregnancies have increased with the use of assisted reproduction, and we expect more women reporting with Rh isoimmunization among multiple gestation in near future. Intrauterine transfusion in singleton itself is technically difficult and requires a lot of skill and precision. Performing double/triple transfusion in twins/triplets is expected to be more demanding.

Aim

To create awareness on the technical difficulties encountered in intrauterine transfusion in twins and triplets.

Methodology

We report a case series of four Rh-isoimmunized twins/triplets in 5 years who presented with severe anemia requiring intrauterine transfusion.

Results

Each of the four sets of cases had their own intricacies that needed to be pondered before tackling them as not much was available in the literature. In Case 1, the first twin intrauterine transfusion in our 20-year-long experience, the difficulty in the approach to the first twin due to a posteriorly placed placenta has been highlighted. Case 2 was rare due to the concomitant presence of atypical antibodies in the mother in addition to Rh-D isoimmunization that made it difficult to cross match any donor blood for intrauterine transfusion. The third case was exclusive due to its monochorionic-diamniotic nature of the twins where the impact of inter-twin anastomosis on the transfusion was to be taken into consideration. Fourth case was a triplet gestation where the difficulty of which cord to be assigned to which fetus, the crowded space for intervention, as well as the risk of prolonged operative time and associated risk of preterm/premature rupture of membranes were our concern.

Conclusion

Intrauterine transfusion (IUT) in twins/triplets is challenging. Difficulties encountered during IUT in multifetal gestation are due to different or uncertain chorionicity, intraplacental anastomosis between vessels, different degree of anemia in twins, difficult to ascertain cord-fetus relationship and difficulty to reach placental insertion site due to crowding by multiple fetal parts.

Early-onset hypoproliferative anemia in an intrauterine-transfused neonate with severe Rh hemolytic disease

A fetus with features of hydrops was given intra-uterine transfusion at 27 weeks and 31 weeks of gestation. Mother had been alloimmunized with anti-D and anti-C antibodies. At birth, laboratory investigations revealed bone marrow suppression along with features of hemolytic anemia. The neonate was started on a combination of phototherapy and intravenous immunoglobulin. During the course, the neonate was transfused with one unit of packed red cells (top-up transfusion). Neonatal hyperbilirubinemia responded to phototherapy and the bone marrow activity spontaneously resumed after 3 weeks of life. In neonates with anemia at birth who have history of multiple intra-uterine transfusions, early-onset hypoproliferative anemia should be considered.

Prenatal management of fetal anemia due to pyruvate kinase deficiency: A case report

BACKGROUND

Pyruvate Kinase (PK) deficiency is the most common enzyme defect of glycolysis, leading to congenital hemolytic anemia, which can occur during the neonatal period.

STUDY DESIGN AND METHODS

We report the prenatal management of fetal anemia related to PK deficiency in a family with a severe proband.

RESULTS

The couple had a first child born with hydrops, whose PK deficiency was diagnosed at 18 months of life. He was treated with allogeneic bone marrow transplantation. The second child was free from disease. For the third pregnancy, the amniocentesis revealed a PK deficiency. Weekly ultrasound monitoring of the middle cerebral artery velocity allowed the detection of severe fetal anemia. Two intrauterine red blood cell transfusions (IUTs) were performed, raising the fetal hemoglobin from 6.6 to 14.5 g/dl at 28 weeks' gestation and from 8.9 to 15.3 g/dl at 31 weeks. A hematopoietic stem cell allograft was discussed prenatally but not chosen, as it would not have significantly changed the perinatal prognosis. The patient delivered a 2730 g girl at 37 weeks, with hemoglobin of 13.6 g/dl. The child presented with neonatal jaundice treated with phototherapy and received postnatal transfusions.

DISCUSSION

When a proband is identified in a family, fetal investigation is warranted, to set up third-trimester ultrasound surveillance and perinatal management. In case of fetal severe anemia of unknown etiology, the workup on fetal blood sampling before IUT should comprise the search for erythrocytes enzymopathies, such as PK deficiency. IUTs allow safer full-term delivery in cases with PK deficiency.

Survey of intrauterine red blood cell (RBC) transfusion practices in the United States

BACKGROUND

A paucity of data exists about the current practice of fetal red blood cell (RBC) transfusion in the United States (US). This investigation describes intrauterine transfusion (IUT) RBC product selection and processing practices at different US institutions.

METHODS

A transfusion medicine and maternal-fetal medicine (MFM) team designed a survey to interrogate and characterize RBCs utilized for IUT. This survey was distributed to seventy US institutions with fetal treatment centers (October 2020-April 2021) identified through the NAFTNet (North American Fetal Therapy Network).

RESULTS

Thirty-seven institutions responded (response rate 53%, 37/70), but five were excluded for not performing IUTs. Most (84%; 27/32) performed 1-24 IUTs annually; two performed >50 IUTs/year. Group O, Rh(D) negative RBC units were always used by 66% (21/32), and 75% (24/32) provided hemoconcentrated RBCs by washing (17/24) or dry packing (6/24). Overall, 66% (21/32) targeted a hematocrit ≥75%. Fifty percent provided both leukocyte-reduced and CMV-negative RBC units. Irradiation of RBC units was performed within 6 h of issue at 63% (20/32) of sites. Most (81%, 26/32) used RBC units at <7 days of age after collection, 56% (18/32) always provided washed RBC units, while 19% (6/32) issued washed RBC only if fresh units are unavailable. Implicated maternal RBC alloantibodies were matched for 78% (25/32) of the time. The transfused volume was universally determined by the MFMs.

DISCUSSION

Heterogeneity and lack of standardization exist in RBC product selection and special processing steps for IUTs in the US. Hence, the establishment of a consensus to standardize IUT protocols is needed.

In utero transplantation of myoblasts and adipose-derived mesenchymal stem cells to murine models of Duchenne muscular dystrophy does not lead to engraftment and frequently results in fetal death

Introduction

Duchenne muscular dystrophy (DMD) is a progressive disease that leads to damage of muscle and myocardium due to genetic abnormalities in the dystrophin gene. In utero cell transplantation that might facilitate allogenic transplantation is worth considering to treat this disease.

Methods

We performed allogeneic in utero transplantation of GFP-positive myoblasts and adipose-derived mesenchymal stem cells into murine DMD model animals. The transplantation route in this study was fetal intraperitoneal transplantation and transplacental transplantation. Transplanted animals were examined at 4-weeks old by immunofluorescence staining and RT-qPCR.

Results

No GFP-positive cells were found by immunofluorescence staining of skeletal muscle and no GFP mRNA was detected by RT-qPCR in any animal, transplantation method and cell type. Compared with previous reports, myoblast transplantation exhibited an equivalent mortality rate, but adipose-derived stem cell (ASC) transplantation produced a higher mortality rate.

Conclusions

In utero transplantation of myoblasts or ASCs to murine models of DMD does not lead to engraftment and, in ASC transplantation primarily, frequently results in fetal death.

Human parvovirus B19 infection in a pregnant patient resulting in severe hydrops, foetal death and persistent infection

Human parvovirus B19 (B19V) is the aetiological agent of erythema infectiosum. Primary infection during pregnancy can be transmitted to the foetus and cause foetal abnormalities related to depletion of erythrocyte progenitor cells, including congenital anaemia, hydrops, and foetal death. In this paper we report the detection of B19V infection in a pregnant patient, which onset occurred without appreciable signs and symptoms until she developed inappropriate contractions for gestational age and fluid loss. B19V infection resulted in severe hydrops fetalis with a fatal course for the foetus, while persisted in the mother at least 12 months after foetal death. The objective of this report is to highlight the importance of optimizing B19V diagnosis through early suspicion and testing during pregnancy. Knowing the mother’s immune status before or at the beginning of gestation can contribute, together with early diagnosis, to improve the management of patients at risk.

Prenatal Somatic Cell Gene Therapies: Charting a Path Toward Clinical Applications (Proceedings of the CERSI-FDA Meeting)

We are living in a golden age of medicine in which the availability of prenatal diagnosis, fetal therapy, and gene therapy/editing make it theoretically possible to repair almost any defect in the genetic code. Furthermore, the ability to diagnose genetic disorders before birth and the presence of established surgical techniques enable these therapies to be delivered safely to the fetus. Prenatal therapies are generally used in the second or early third trimester for severe, life-threatening disorders for which there is a clear rationale for intervening before birth. While there has been promising work for prenatal gene therapy in preclinical models, the path to a clinical prenatal gene therapy approach is complex. We recently held a conference with the University of California, San Francisco-Stanford Center of Excellence in Regulatory Science and Innovation, researchers, patient advocates, regulatory (members of the Food and Drug Administration), and other stakeholders to review the scientific background and rationale for prenatal somatic cell gene therapy for severe monogenic diseases and initiate a dialogue toward a safe regulatory path for phase 1 clinical trials. This review represents a summary of the considerations and discussions from these conversations.

Intrauterine transfusion in 103 fetuses with severe anemia caused by parvovirus infection. A multicenter retrospective study

PURPOSE

Evaluating procedure-related complications and perinatal outcomes after intrauterine transfusion (IUT) before or after 20⁺⁰ weeks of gestation in fetuses with severe anemia due to intrauterine human parvovirus B19 infection.

METHODS

A retrospective study investigating fetuses requiring IUT for fetal Parvo B19 infection in two tertiary referral centers between December 2002 and December 2021. Procedure-related complications, intrauterine fetal death (IUFD), and perinatal outcome were correlated to gestational age (GA) at first IUT, the presence of hydrops and fetal blood sampling results.

RESULTS

A total of 186 IUTs were performed in 103 fetuses. The median GA at first IUT was 19⁺³ (13⁺⁰-31⁺⁴) weeks of gestation. IUFD occurred in 16/103 fetuses (15.5%). Overall survival was 84.5% (87/103). Hydrops (p = 0.001), lower mean hemoglobin at first IUT (p = 0.001) and low platelets (p = 0.002) were strongly associated with IUFD. There was no difference observed in fetuses transfused before or after 20⁺⁰ weeks of gestation.

CONCLUSION

IUT is a successful treatment option in fetuses affected by severe anemia due to parvovirus B19 infection in specialized centers. In experienced hands, IUT before 20 weeks is not related to worse perinatal outcome.

Maternal bleeding complications in pregnancies affected by red blood cell alloimmunization

OBJECTIVE

To investigate whether women with red blood cell (RBC)¹ alloimmunization are more likely to experience bleeding complications during pregnancy or delivery than women without RBC alloimmunization.

STUDY DESIGN

Retrospective study involving all singleton pregnancies affected by RBC alloimmunization and without pre-existing maternal bleeding disorders or placenta previa, from 1 July 1999 to 30 June 2019 ("cases"). Only bleedings not related to invasive procedures (amnio- or cordocenteses) were included. Patients who were already at increased risk of pre- or perinatal bleeding due to their medical history (pre-existing bleeding disorders, antithrombotic therapy), or known obstetrics parameters (placental abnormalities etc.) were not included a priori. Cases were compared to controls without RBC alloimmunization, matched for maternal age and body mass index, from the same tertiary referral center in Austria.

RESULTS

130 cases were compared to 130 controls. Cases had significantly more previous pregnancies and miscarriages and their newborns had lower birthweight and were more often transferred to the intensive care unit than newborns of controls. 18/130 (13.8%) cases, compared to 8/130 (6.2%) controls experienced any bleeding during pregnancy or delivery (p = 0.061). Bleeding most often happened during the third trimester (cases: 4.6% vs. controls 0.8%, p = 0.12) and during or after delivery (cases: 7.7% vs. controls: 4.6%, p = 0.168). Binary logistic regression for the prediction of any bleeding complication during pregnancy, delivery or postpartum revealed immunization against RBC antigens as the only independent contributor (p = 0.04). Age, smoking, or previous obstetric history had no influence on the likelihood of maternal bleeding complications. Neither RBC antibody specificity nor titers were predictive of maternal bleeding during pregnancy or delivery.

CONCLUSION

Pregnancies affected by RBC alloimmunization might be at increased risk of maternal bleeding complications during pregnancy and delivery.

Extremely Rare Case of Fetal Anemia Due to Mitochondrial Disease Managed with Intrauterine Transfusion

This report describes a rare case of fetal anemia, confirmed as a mitochondrial disease after birth, treated with intrauterine transfusion (IUT). Although mitochondrial diseases have been described in newborns, research on their prenatal features is lacking. A patient was referred to our institution at 32 gestational weeks owing to fetal hydrops. Fetal anemia was confirmed by cordocentesis. After IUT had been performed three times, the anemia and associated fetal hydrops showed improvement. However, after birth, the neonate had recurrent pancytopenia and lactic acidosis. He was eventually diagnosed with Pearson syndrome and died 2 months after birth. This is the first case report of fetal anemia associated with mitochondrial disease managed with IUT.

Severe Neonatal Anemia Due to Spontaneous Massive Fetomaternal Hemorrhage at Term: An Illustrative Case with Suspected Antenatal Diagnosis and Brief Review of Current Knowledge

Fetomaternal hemorrhage is defined as transfer of fetal blood into placental circulation and therefore into maternal circulation during pregnancy, and represents an important contributor to intrauterine fetal demise and neonatal death. The condition is rarely diagnosed prenatally because clinical findings are often nonspecific, and it is unpredictable. In this paper we present an illustrative case of massive spontaneous fetomaternal hemorrhage where the diagnosis was highly suspected antenatally based on maternal reported reduced fetal movements, abnormal suggestive cardiotocographic trace, and increased peak systolic velocity in the fetal middle cerebral artery. We discuss obstetrical and neonatal management and review the current knowledge in the literature. Maintaining a high index of suspicion for this condition allows the obstetrician to plan for adequate diagnostic tests, arrange intrauterine treatment or delivery, and prepare the neonatal team.

Complications of intravascular intrauterine transfusion for Rh alloimmunization

BACKGROUND

Intravascular intrauterine transfusion (IUT) is considered a safe procedure, but complications still occur, including fatalities.

OBJECTIVE

Review the outcomes of Rh alloimmunization, including indications and possible complications.

DESIGN

Retrospective cohort (medical record review).

SETTING

Tertiary care center.

PATIENTS AND METHODS

We retrieved the records for all mothers who had an IUT for Rh alloimmunization between January 2009 and August 2019. We collected data on complications, post-transfusion hemoglobin and antibody combinations.

MAIN OUTCOME MEASURE

Complications of IUT.

SAMPLE SIZE

119 mothers with 154 fetuses (154 different pregnancies).

RESULTS

The 154 fetuses had 560 intrauterine transfusions. The median pre-IUT hemoglobin was a median of 8.0 g/dL while the median post-IUT hemoglobin 16 g/dL. Immediate procedure-related complications included fetal bradycardia in 2.7%, significant bleeding from the cord puncture site (for more than 2 minutes in 0.9%), and contractions in 0.9%. Eight (5.2%) were delivered by cesarean delivery due to IUT-specific complications such as post-procedure fetal bradycardia. Intrauterine fetal death complicated 8.4% of the pregnancies (13 fetuses). Phototherapy was required in 76 (49.4%), postnatal blood transfusions in 17 (11%), and exchange transfusion in 11 (7.1%). Neonatal death occurred 8 (5.2%). Data were insufficient to assess associations of complications with antibody combinations.

CONCLUSIONS

Intrauterine transfusion is an effective treatment with high survival rates (around 90% for cases of Rh alloimmunization).

LIMITATIONS

Case series.

CONFLICT OF INTEREST

None.

A very preterm infant born to mother of mirror syndrome secondary to fetomaternal hemorrhage: a case report

Background

Mirror syndrome (MS) is defined as maternal edema with fetal hydrops and placental edema with different etiologies, such as rhesus isoimmunization and twin-twin transfusion syndrome. Herein, we showcased a unique MS case secondary to fetomaternal hemorrhage (FMH).

Case presentation

A 32-year-old gravida 2 para 0 woman diagnosed with fetal hydrops was admitted to our hospital. Maternal laboratory tests revealed anemia, slightly increased creatinine and uric acid levels, hypoproteinemia, and significantly increased alpha-fetoprotein and hemoglobin-F levels. Therefore, FMH was diagnosed initially. Two days after admission, the woman had unexpectedly progressive anasarca and started to feel chest distress, palpitations, lethargy, and oliguria, and MS was suspected. An emergency cesarean section was performed to terminate the pregnancy. The maternal clinical symptoms and laboratory tests rapidly improved after delivery. A very preterm infant with a 2080-g birthweight at 31 weeks gestation survived after emergency cesarean section, active resuscitation, emergency blood transfusion, abdominocentesis, and advanced life support.

Conclusions

FMH could develop into MS, providing new insights into the etiology of MS. Once MS is diagnosed, emergency cesarean section might be an alternative treatment. The very preterm infant survived with a favorable long-term outcome, and a well-trained perinatal work team is needed for such cases.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-04179-5.

Conservative Management of Presumed Fetal Anemia Secondary to Maternal Chemotherapy for Acute Myeloid Leukemia

Acute myeloid leukemia occurs rarely during pregnancy. When it is diagnosed remote from term, treatment in the form of daunorubicin plus cytarabine induction with consolidative cytarabine is typically undertaken after the first trimester. There is little data to guide fetal monitoring, in particular, whether and how often middle cerebral artery peak systolic velocity (MCA PSV) should be measured to screen for fetal anemia. Cytarabine may be particularly myelosuppressive to the fetus, but information pertaining to the management of this complication is also lacking in published literature. To our knowledge, we present the first case of presumed severe fetal anemia related to in utero exposure to chemotherapy that was managed conservatively with close sonographic monitoring, including serial measurement of MCA PSV. This case suggests that in the absence of hydrops fetalis or other signs of fetal decompensation, expectant management with ultrasound twice weekly, including MCA PSV, is appropriate. Ultrasounds may be decreased to weekly when MCA PSV does not suggest fetal anemia. Screening for fetal anemia can provide helpful information to guide the timing of chemotherapy administration and delivery. Key Points Chemotherapy for acute myeloid leukemia can cause fetal anemia.Fetal MCA PSV can be used to safely and effectively screen for fetal anemia.Observation of fetal anemia due to chemotherapy is reasonable, in the absence of hydrops.Monitoring of fetal MCA PSV can help guide timing of chemotherapy and delivery.

Prenatal politics: fetal surgery, abortion and disability rights in the United States

While fetal surgery-and pregnancy termination as a possible therapeutic alternative-have been examined in a number of studies, very few have addressed the issues and tensions that arise when prenatal surgery is considered from the standpoint of Disability Studies. This article will expose these concerns by tracing the medical development of fetal surgery; the arguments for and against prenatal surgery; and the connections between fetal surgery, abortion, and disability rights. Like other dimensions of the life cycle that involve reproduction, prenatal surgery has become highly politicized in the United States which has, to a certain extent, stalled critical discussion. However, the skepticism with which many disability rights advocates and policymakers approach prenatal medical intervention in general has opened a new space for active debate concerning fetal surgery in terms of how it medicalizes pregnancy, pathologizes diversity, contributes to the valuation of life, and emphasizes 'perfect babies' at any cost.

Tolerance induction and microglial engraftment after fetal therapy without conditioning in mice with Mucopolysaccharidosis type VII

Mucopolysaccharidosis type VII (MPS7) is a lysosomal storage disorder (LSD) resulting from mutations in the β-glucuronidase gene, leading to multiorgan dysfunction and fetal demise. While postnatal enzyme replacement therapy (ERT) and hematopoietic stem cell transplantation have resulted in some phenotypic improvements, prenatal treatment might take advantage of a unique developmental window to penetrate the blood-brain barrier or induce tolerance to the missing protein, addressing two important shortcomings of postnatal therapy for multiple LSDs. We performed in utero ERT (IUERT) at E14.5 in MPS7 mice and improved survival of affected mice to birth. IUERT penetrated brain microglia, whereas postnatal administration did not, and neurological testing (after IUERT plus postnatal administration) showed decreased microglial inflammation and improved grip strength in treated mice. IUERT prevented antienzyme antibody development even after multiple repeated postnatal challenges. To test a more durable treatment strategy, we performed in utero hematopoietic stem cell transplantation (IUHCT) using congenic CX3C chemokine receptor 1-green fluorescent protein (CX3CR1-GFP) mice as donors, such that donor-derived microglia are identified by GFP expression. In wild-type recipients, hematopoietic chimerism resulted in microglial engraftment throughout the brain without irradiation or conditioning; the transcriptomes of donor and host microglia were similar. IUHCT in MPS7 mice enabled cross-correction of liver Kupffer cells and improved phenotype in multiple tissues. Engrafted microglia were seen in chimeric mice, with decreased inflammation near donor microglia. These results suggest that fetal therapy with IUERT and/or IUHCT could overcome the shortcomings of current treatment strategies to improve phenotype in MPS7 and other LSDs.

Role of Imaging in Obstetric Interventions: Criteria, Considerations, and Complications

US has an established role in the prenatal detection of congenital and developmental disorders. Many pregnant women undergo US at 18-20 weeks of gestation for assessment of fetal anatomy and detection of structural anomalies. With advances in fetoscopy and minimally invasive procedures, in utero fetal interventions can be offered to address some of the detected structural and physiologic fetal abnormalities. Most interventions are reserved for conditions that, if left untreated, often cause in utero death or a substantially compromised neonatal outcome. US is crucial for preprocedural evaluation and planning, real-time procedural guidance, and monitoring and assessment of postprocedural complications. Percutaneous needle-based interventions include in utero transfusion, thoracentesis and placement of a thoracoamniotic shunt, vesicocentesis and placement of a vesicoamniotic shunt, and aortic valvuloplasty. Fetoscopic interventions include myelomeningocele repair and tracheal balloon occlusion for congenital diaphragmatic hernia. In rare cases, open hysterotomy may be required for repair of a myelomeningocele or resection of a sacrococcygeal teratoma. Monochorionic twin pregnancies involve specific complications such as twin-twin transfusion syndrome, which is treated with fetoscopic laser ablation of vascular connections, and twin reversed arterial perfusion sequence, which is treated with radiofrequency ablation. Finally, when extended placental support is necessary at delivery for repair of congenital high airway obstruction or resection of lung masses, ex utero intrapartum treatment can be planned. Radiologists should be aware of the congenital anomalies that are amenable to in utero interventions and, when necessary, consider referral to centers where such treatments are offered. Online supplemental material and the slide presentation from the RSNA Annual Meeting are available for this article. ^©RSNA, 2021.

A comparative study on perinatal outcomes of red blood cell-alloimmunized pregnancies with anti-RhD in combination and anti-RhD alone in China

BACKGROUND AND OBJECTIVES

The advent of intrauterine transfusion (IUT) has improved the survival of severe foetal anaemia. The aim of this study was to compare the perinatal outcomes of red blood cell (RBC)-alloimmunized pregnancies with anti-RhD in combination and anti-RhD alone in China.

MATERIALS AND METHODS

A retrospective study was conducted involving RBC-alloimmunized pregnancies with anti-RhD in combination and anti-RhD alone admitted to The First Affiliated Hospital, Sun Yat-sen University, between January 2007 and December 2019. Obstetric data and neonatal outcomes were compared.

RESULTS

A total of 165 alloimmunized pregnancies were identified, with 32 pregnancies in the anti-RhD-in-combination group (25 pregnancies with anti-RhD + anti-RhC and 7 pregnancies with anti-RhD + anti-RhE) and 133 pregnancies in the anti-RhD-alone group. The anti-RhD-in-combination group had significantly higher frequency of IUTs than the anti-RhD-alone group (59.4% [19/32] vs. 30.1% [40/133]; p < 0.01). The postnatal frequency of top-up transfusions was significantly higher in the anti-RhD in combination group than the anti-RhD-alone group (90.6% [29/32] vs. 70.7% [94/133]; p = 0.02). There was no significant difference in the frequency of exchange transfusions (ETs) between the two groups (15.6% [5/32] vs. 17.3% [23/133]; p = 0.82).

CONCLUSIONS

Compared to alloimmunized pregnancies with anti-RhD alone, pregnancies with anti-RhD in combination with anti-RhC or anti-RhE have an increased requirement for antenatal IUTs and postnatal top-up transfusions but do not have an increased need for ETs.

Perinatal outcomes and survival predictors of severe red-cell alloimmunization treated by intrauterine transfusion

OBJECTIVE

To evaluate perinatal survival rates and predictors in severely anemic fetuses that underwent intrauterine transfusion (IUT).

METHOD

This was a retrospective study of both Turkish and Syrian patients who underwent IUT for fetal anemia due to Rh alloimmunization between 2015 and 2019. The association between pretransfusion factors and perinatal survival was evaluated by multivariate logistic regression. Receiver operating characteristics (ROC) curves were used to identify the level of fetal hemoglobin deficits that predict perinatal survival.

RESULTS

Eighty-seven IUTs were performed in 42 pregnancies. Approximately 75% of fetuses were severely anemic and the overall perinatal survival rate was 50%. The survival rate was better in Syrian refugees compared to Turkish patients (71.4% vs. 39.3%, p < 0.05). In univariate analysis, hydrops presence (odds ratio [OR] = 0.2; 95% confidence interval [CI] = 0.05-0.7; p < 0.05), first IUT week (OR = 1.4; 95% CI = 1.1-1.8; p < 0.05), pretransfusion hemoglobin level (OR = 1.99; 95% CI = 1.22-3.27; p < 0.05), hemoglobin deficit (OR = 0.5; 95% CI = 0.3-0.8; p < 0.05), and birth week (OR = 2.3; 95% CI = 1.3-3.9; p < 0.05) were associated with survival. However in a multivariate analysis, only hemoglobin deficit (OR = 0.47; 95% CI = 0.22-0.99; p < 0.05) and birth week (OR = 3.3; 95% CI = 1.1-10.3; p < 0.05) were found to be associated with survival. On ROC analysis, a hemoglobin deficit of ≤6.25 g/dl showed a sensitivity of 0.95 and specificity of 0.62 for predicting perinatal survival.

CONCLUSION

Despite the improvement in the treatment of fetal anemia, perinatal survival rate remains extremely low in severely anemic cases. Among pretransfusion factors, hemoglobin deficit seemed to be most important in predicting survival during fetal anemia.

A narrative review of in utero gene therapy: advances, challenges, and future considerations

The field of in utero gene therapy (IUGT) represents a crossroad of technologic advancements and medical ethical boundaries. Several strategies have been developed for IUGT focusing on either modifying endogenous genes, replacing missing genes, or modifying gene transcription products. The list of candidate diseases such as hemoglobinopathies, cystic fibrosis, lysosomal storage disorders continues to grow with new strategies being developed as our understanding of their respective underlying molecular pathogenesis increases. Treatment in utero has several distinct advantages to postnatal treatment. Biologic and physiologic phenomena enable the delivery of a higher effective dose, generation of immune tolerance, and the prevention of phenotypic onset for genetic diseases. Therapeutic technology for IUGT including CRISPR-Cas9 systems, zinc finger nucleases (ZFN), and peptide nucleic acids (PNAs) has already shown promise in animal models and early postnatal clinical trials. While the ability to detect fetal diagnoses has dramatically improved with developments in ultrasound and next-generation sequencing, treatment options remain experimental, with several translational gaps remaining prior to implementation in the clinical realm. Complicating this issue, the potential diseases targeted by this approach are often debilitating and would otherwise prove fatal if not treated in some manner. The leap from small animals to large animals, and subsequently, to humans will require further vigorous testing of safety and efficacy.

Nationwide survey of intrauterine blood transfusion for fetal anemia in Japan

AIM

The present study investigated the current situation regarding intrauterine blood transfusion (IUT) for fetal anemia in Japan.

METHODS

We conducted a nationwide, multicenter, retrospective cohort questionnaire survey for cases that underwent IUT from 2011 to 2015. The questionnaire required perioperative information, indications, details of the procedure, procedure-related complications, and neonatal morbidity.

RESULTS

A total of 100 IUT procedures were performed in 66 cases at 19 institutions during the study period. The most frequent indication of IUT was complicated monochorionic diamniotic (MCDA) twins in 28 (42.4%) cases, followed by 16 (24.2%) cases of red-cell alloimmunization, and 10 (15.2%) cases of parvovirus B19 infection. IUT was performed through the umbilical cord in the vast of majority cases (92%). Bleeding from the IUT site was the most common adverse event (40%). Two cases (2%) underwent emergency cesarean section after the procedure. There were no cases of rupture of membrane or intrauterine infection after IUT. The neonatal survival rate was 77.3% in the 66 total cases and 64% in the hydrops cases. The neonatal survival rates in MCDA twins, red-cell alloimmunization, and parvovirus B19 infection were 75%, 93.8%, and 70%, respectively.

CONCLUSIONS

IUT was performed for mainly three indications in Japan: MCDA twins, red-cell alloimmunization, and parvovirus B19 infection. The incidences of severe adverse events seemed very low. The outcomes after IUT were favorable with variations in survival rates according to indications. However, further studies with long-term follow-up will be required to assess the effectiveness of IUT, especially for complicated MCDA twins.

Hemolytic Disease of the Fetus and Newborn: Historical and Current State

Hemolytic disease of the fetus and newborn (HDFN) is an immune-mediated disorder affecting neonates globally, with a range of clinical presentations from severe and life threatening to mild or even asymptomatic. Historically, HDFN has been responsible for a large proportion of perinatal mortality, and, despite advances in diagnosis and management, this morbidity and mortality has not been eradicated. Blood banking techniques and blood transfusion have contributed to improved prophylaxis and management, drastically improving the outcome of newborns with HDFN over the last century.

Therapeutic Approaches to Treat Mitochondrial Diseases: "One-Size-Fits-All" and "Precision Medicine" Strategies

Primary mitochondrial diseases (PMD) refer to a group of severe, often inherited genetic conditions due to mutations in the mitochondrial genome or in the nuclear genes encoding for proteins involved in oxidative phosphorylation (OXPHOS). The mutations hamper the last step of aerobic metabolism, affecting the primary source of cellular ATP synthesis. Mitochondrial diseases are characterized by extremely heterogeneous symptoms, ranging from organ-specific to multisystemic dysfunction with different clinical courses. The limited information of the natural history, the limitations of currently available preclinical models, coupled with the large variability of phenotypical presentations of PMD patients, have strongly penalized the development of effective therapies. However, new therapeutic strategies have been emerging, often with promising preclinical and clinical results. Here we review the state of the art on experimental treatments for mitochondrial diseases, presenting "one-size-fits-all" approaches and precision medicine strategies. Finally, we propose novel perspective therapeutic plans, either based on preclinical studies or currently used for other genetic or metabolic diseases that could be transferred to PMD.

Immunohematologic aspects of alloimmunization and alloantibody detection: A focus on pregnancy and hemolytic disease of the fetus and newborn

Alloimmunization to non-ABO, red blood cell (RBC) antigens remains one of the most clinically-relevant complexities faced by blood banking practitioners. In the setting of transfusion therapy, these antibodies raise risks for incompatibilities, while for pregnant patients they can mediate deadly forms of hemolytic disease of the fetus and newborn. As such, a thorough understanding of pathways that lead to alloimmunization, as well as the tools used by blood banks to detect alloantibodies, is critical to transfusion practice. In this review, in which alloimmunization in the setting of pregnancy will be emphasized, we will review: 1) the clinical impacts of RBC alloantibodies in the peri-partum period; 2) the current pathophysiologic mechanisms thought to influence non-ABO antigen alloimmunization; 3) the strengths and weaknesses of laboratory tools used in aiding alloimmunization detection; and 4) future directions of the transfusion community related to alloimmunization impacting pregnancy.

SARS-CoV-2 Infection and COVID-19 During Pregnancy: A Multidisciplinary Review

The global pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the cause of coronavirus disease 2019 (COVID-19), has been associated with worse outcomes in several patient populations, including the elderly and those with chronic comorbidities. Data from previous pandemics and seasonal influenza suggest that pregnant women may be at increased risk for infection-associated morbidity and mortality. Physiologic changes in normal pregnancy and metabolic and vascular changes in high-risk pregnancies may affect the pathogenesis or exacerbate the clinical presentation of COVID-19. Specifically, SARS-CoV-2 enters the cell via the angiotensin-converting enzyme 2 (ACE2) receptor, which is upregulated in normal pregnancy. Upregulation of ACE2 mediates conversion of angiotensin II (vasoconstrictor) to angiotensin-(1-7) (vasodilator) and contributes to relatively low blood pressures, despite upregulation of other components of the renin-angiotensin-aldosterone system. As a result of higher ACE2 expression, pregnant women may be at elevated risk for complications from SARS-CoV-2 infection. Upon binding to ACE2, SARS-CoV-2 causes its downregulation, thus lowering angiotensin-(1-7) levels, which can mimic/worsen the vasoconstriction, inflammation, and pro-coagulopathic effects that occur in preeclampsia. Indeed, early reports suggest that, among other adverse outcomes, preeclampsia may be more common in pregnant women with COVID-19. Medical therapy, during pregnancy and breastfeeding, relies on medications with proven safety, but safety data are often missing for medications in the early stages of clinical trials. We summarize guidelines for medical/obstetric care and outline future directions for optimization of treatment and preventive strategies for pregnant patients with COVID-19 with the understanding that relevant data are limited and rapidly changing.

Short-term outcomes following intrauterine transfusions for fetal anaemia: A retrospective cohort study

BACKGROUND

Intrauterine transfusion (IUT) is the accepted standard for management of severe fetal anaemia. However, fetal transfusion may be associated with procedural complications such as fetal demise. There is a paucity of recent data on outcomes for severe fetal anaemia in Australia as compared with published outcomes from large international centres.

AIMS

To review the indications for and the procedural, obstetric and neonatal outcomes following intrauterine transfusion for fetal anaemia conducted at the New South Wales Fetal Therapy Centre (NSW FTC).

MATERIALS AND METHODS

Retrospective cohort study conducted between 2005 and 2017 of the outcomes of 85 IUT procedures (39 pregnancies). Data collected included maternal demographics, procedural and obstetric details and short-term neonatal outcomes.

RESULTS

Complete outcome data were available for 36/39 pregnancies. Red cell antibodies were the main indication for fetal transfusion (79%, predominantly D, Kell and other Rhesus antibodies) with parvovirus accounting for 8% of procedures. IUT was associated with a pregnancy loss rate of 1.2%/procedure, amounting to 2.6%/pregnancy. Fetal losses were limited to those complicated by hydrops prior to IUT (3/10 hydrops vs 0/26 non-hydropic; P = 0.003).

CONCLUSIONS

Procedural outcomes at NSW FTC compare favourably with international centres (1.1-8.7% procedural loss rate). However, this comparison is limited, as no procedures were performed during the last 24 months of the study. Given this, a nationwide audit is recommended to help guide appropriate centralisation of procedures and thereby maximise clinician experience and outcome.

Red cell alloimmunization: A 2020 update

Management of maternal red cell alloimmunization has been revolutionized over the last 60 years. Advances in the prevention, screening, diagnosis, and treatment of alloimmune-induced fetal anemia make this condition an exemplar for contemporary practice in fetal therapy. Since survival is now an expectation, attention has turned to optimization of long-term outcomes following an alloimmunized pregnancy. In this review, the current management of red cell alloimmunization is described. Current research and future directions are discussed with particular emphasis on later life outcomes after alloimmune fetal anemia.

Mortality and hospital readmissions in the first year of life after intra-uterine and neonatal blood product transfusions: A population data linkage study

AIM

Blood product transfusions are a potentially life-saving therapy for fetal and neonatal anaemia, but there is limited population-based research on outcomes. We aimed to describe mortality, readmission and average hospital stay in the first year of life for infants with or without intra-uterine or neonatal blood product transfusions.

METHODS

Linked birth, hospital and deaths data from New South Wales, Australia (January 2002-June 2014) were used to identify singleton infants (≥23 weeks' gestation, surviving to 29 days; n = 1 089 750) with intra-uterine or neonatal transfusion or no transfusion. Rates of mortality and readmission in the first year (29-365 days) and days in hospital were calculated.

RESULTS

Overall, 68 (0.06/1000) infants had experienced intra-uterine transfusion and 4332 (3.98/1000) neonatal transfusion. Transfusion was more common among those born at earlier gestational ages requiring invasive ventilation. Mortality, readmissions and average days in hospital were higher among transfused than non-transfused infants. Over half of infants with intra-uterine and neonatal transfusion had ≥1 readmission in the first 29-365 days (55.9 and 51.8%, respectively), and around a quarter had ≥2 (20.6 and 28.5%, respectively) compared with 15.3% with ≥1 and 3.5% with ≥2 in the non-transfused group.

CONCLUSION

Infants with a history of blood product transfusion, particularly those needing a neonatal transfusion, had higher mortality and more frequent contact with the hospital system in the first year of life than those infants with no history of transfusion.

Perinatal outcomes of intrauterine transfusion for foetal anaemia due to red blood cell alloimmunisation

The aim of this study was to evaluate the maternal and neonatal outcomes of patients who underwent intrauterine transfusion (IUT) for foetal anaemia due to red blood cell alloimmunisation and to determine the factors that affected the outcomes. All pregnancies that were treated with IUT due to Rh immunisation between January 2015 and June 2018 in the Kanuni Sultan Süleyman Training and Research Hospital, Department of Obstetrics and Gynaecology, were evaluated retrospectively. IUT due to non-Rh alloimmunisation, parvovirus B19 infection, chronic fetomaternal haemorrhage and foetal anaemia due to homozygous alpha-thalassemia were not included in the study. The perinatal and neonatal outcomes of the patients were retrospectively analysed. The gestational age, ultrasonography findings before and after IUT, laboratory results, complications related to IUT, and data on the newborns were recorded. The cases were divided into two groups, those with complication and those without complications, and their perinatal outcomes were compared. A total of 110 IUTs were performed in 42 foetuses. The survival rate after transfusion was 80.95%. Procedure-related complications were found in 12.7% of cases. There were no significant differences between the demographic and clinical characteristics of the patients with and without complications. The survival rate was lower and perinatal mortality was higher in foetuses with hydrops fetalis. IUT is a safe and effective procedure that can be used in the treatment of foetal anaemia in experienced centres. Survival rates can be increased by referring patients to experienced perinatology centres, by improving the IUT technique, and by reducing technique-related complications.Impact statementWhat is already known on this subject? The predominant use of IUT is to treat foetal anaemia due to red blood cell alloimmunisation. Despite the decrease after anti-D immune globulin prophylaxis, Rh immunisation is still a major cause of foetal anaemia. However, foetal survival rates have increased with the use of IUT.What do the results of this study add? The survival rates were increased after the development of a high-resolution ultrasound. Because foetal monitoring can be performed by ultrasonography, cord accidents and overload findings can be detected during transfusion, which allows for early interventions and increases survival rates.What are the implications of these findings for clinical practice and/or further research? The IUT procedure can be used in the treatment of foetal anaemia in experienced centres. After the technique was improved, the complication rates related to the procedure were decreased and foetal survival rates were increased. Further studies on the use of different IUT techniques will extend our findings.

Anesthesia for predelivery procedures: ex-utero intrapartum treatment/intrauterine transfusion/surgery of the fetus

PURPOSE OF REVIEW

The aim of this study was to review the current literature on anesthesia for predelivery procedures and to summarize recent findings on anesthesiological methods used.

RECENT FINDINGS

Ex-utero intrapartum treatment (EXIT)-procedures are performed to secure the newborn's oxygenation in case of severe airway obstruction due to multiple conditions. A key feature of EXIT is continued intactness of the maternofetal circulation by uterine relaxation achieved by general anesthesia with high doses of anesthetic gases. A dose reduction may be achieved by combining inhaled anesthesia with propofol. After intrauterine transfusion the anesthesia team needs to be prepared for a potential need of emergency cesarean section. Temporary fetal endoluminal tracheal occlusion and laser coagulation for twin-to-twin transfusion syndrome may be either performed in monitored anesthesia care or neuraxial anesthesia. Neuraxial anesthesia also is a method of choice for fetal valvuloplasty and amniotic band release. Fetal myelomenigocele repair requires general anesthesia with tocolysis.

SUMMARY

Predelivery procedures require a differentiated anesthesia approach depending on the invasiveness of the intervention. Anesthesia ranges from monitored care to neuraxial anesthesia and general anesthesia. Depending on the procedure uterine relaxation and fetal immobilization are crucial for technical success. Interdisciplinary consultation optimizes the anesthesia plan for complex procedures.