Two hundred intrauterine exchange transfusions in severe blood incompatibilities

Management Considerations for Air Medical Transport Programs Transfusing RhD-Positive Red Blood Cell-Containing Products to Females of Childbearing Potential

Recent years have seen increased discussion surrounding the benefits of damage control resuscitation, prehospital transfusion (PHT) of blood products, and the use of whole blood over component therapy. Concurrent shortages of blood products with the desire to provide PHT during air medical transport have prompted reconsideration of the traditional approach of administering RhD-negative red cell-containing blood products first-line to females of childbearing potential (FCPs). Given that only 7% of the US population has blood type O negative and 38% has O positive, some programs may be limited to offering RhD-positive blood products to FCPs. Adopting the practice of giving RhD-positive blood products first-line to FCPs extends the benefits of PHT to such patients, but this practice does incur the risk of future hemolytic disease of the fetus and newborn (HDFN). Although the risk of future fetal mortality after an RhD-incompatible transfusion is estimated to be low in the setting of acute hemorrhage, the number of FCPs who are affected by this disease will increase as more air medical transport programs adopt this practice. The process of monitoring and managing HDFN can also be time intensive and costly regardless of the rates of fetal mortality. Air medical transport programs planning on performing PHT of RhD-positive red cell-containing products to FCPs should have a basic understanding of the pathophysiology, prevention, and management of hemolytic disease of the newborn before introducing this practice. Programs should additionally ensure there is a reliable process to notify receiving centers of potentially RhD-incompatible PHT because alloimmunization prophylaxis is time sensitive. Facilities receiving patients who have had PHT must be prepared to identify, counsel, and offer alloimmunization prophylaxis to these patients. This review aims to provide air medical transport professionals with an understanding of the pathophysiology and management of HDFN and provide a template for the early management of FCPs who have received an RhD-positive red cell-containing PHT. This review also covers the initial workup and long-term anticipatory guidance that receiving trauma centers must provide to FCPs who have received RhD-positive red cell-containing PHT.

Intravenous immunoglobulin in the management of severe early onset red blood cell alloimmunisation

Our objective was to assess the effect of maternal intravenous immunoglobulin (IVIG) administration for severe red blood cell (RBC) alloimmunisation on fetal outcomes. This is a case-control study. Women with a history of severe early onset alloimmunisation resulting in fetal loss in a previous pregnancy and high anti-D or anti-K antibody titres received IVIG in a subsequent pregnancy. We assessed gestational age at first transfusion and fetal outcomes in the subsequent pregnancy and compared these with the outcomes in the previous pregnancy. The most responsible antibody was anti-D in 17 women and anti-K in two others, whilst seven had more than one antibody. In all, 19 women received IVIG in 22 pregnancies, two of which did not even need an intrauterine transfusion (IUT). For previous early losses despite transfusion, IVIG was associated with a relative increase in fetal haemoglobin between treated and untreated pregnancies of 36.5 g/L (95% confidence interval 19.8-53.2, p = 0.0013) and improved perinatal survival (eight of eight vs. none of six, p = 0.001). For previous losses at <20 weeks, it enabled first transfusion deferral in subsequent pregnancies to at least 19.9 weeks (mean 23.2 weeks). Overall, IVIG decreases the severity of haemolytic disease of the fetus and newborn and allows deferral of the first IUT to a safer gestation in severe early-onset RBC alloimmunisation and rarely may even avoid the need for IUT entirely.

Is fetal middle cerebral artery peak systolic velocity correlated with hemoglobin levels in cases of nonimmune fetal anemia?

OBJECTIVES

To establish whether a correlation exists between the fetal middle cerebral artery peak systolic velocity (MCA PSV) and fetal hemoglobin levels before intrauterine transfusion (IUT) in cases of severe fetal anemia.

METHODS

This was a single-center, retrospective study of data from 49 fetuses treated with IUT for fetal anemia between 2003 and 2018. Severe fetal anemia was suspected when MCA PSV was or exceeded 1.55 multiples of the median.

RESULTS

The causes of anemia were largely idiopathic, and the overall survival rate was 57%. MCA PSV and hemoglobin were correlated in all 34 fetuses with alloimmune fetal anemia, whereas the 15 fetuses with nonimmune causes showed no correlation. Of the 15 noncorrelated cases, twin pregnancy was most common, followed by idiopathic causes. All the twin pregnancies involved monochorionic twins. Fetal hydrops, especially ascites, was significantly associated with severe anemia.

CONCLUSIONS

Fetal MCA PSV may not be a reliable independent factor for the diagnosis of severe fetal anemia in nonimmune cases, and the presence of associated hydrops implies that the fetus is more likely to have severe fetal anemia than in a fetus without hydrops.

Fetal anemia: Diagnosis and management

Fetal anemia has been known for many years as a dangerous complication of pregnancy. Its most common causes are maternal alloimmunization and parvovirus B19 infection, although it can be associated with many different pathological conditions including fetal aneuploidies, vascular tumors, and arteriovenous malformations of the fetus or placenta and inherited conditions such as alpha-thalassemia or genetic metabolic disorders. Doppler ultrasonographic assessment of the peak velocity of systolic blood flow in the middle cerebral artery for the diagnosis of fetal anemia and intravascular intrauterine transfusion for its treatment are the current practice standards. Live birth rates as high as 95% have been reported in recent years. The additional role of intravenous immunoglobulin therapy and the long-term consequences of the condition are the subjects of active ongoing research.

Does an intrauterine exchange transfusion improve the fetal prognosis in parvovirus infection cases?

BACKGROUND

Almost 20% of parvovirus B19 foetal infections require intrauterine transfusions. In addition, myocardial dysfunction has been observed in severe parvovirus B19 infections. One objective of an intrauterine exchange transfusion (IUET) is to avoid an overload during the transfusion. Our aim was to study the obstetrical and neonatal outcomes in cases of IUETs performed for foetal parvovirus infections and to compare our survival rate to those studies in which simple in utero transfusions were chosen.

STUDY DESIGN AND METHODS

This was a retrospective monocentre study of all patients followed up for parvovirus B19 infections in which IUETs were performed. An IUET was indicated when foetal hydrops was observed and/or when severe foetal anaemia was diagnosed though an elevation in the middle cerebral artery peak systolic velocity. The characteristics of each pregnancy and the neonatal outcomes were studied until hospital discharge.

RESULTS

Thirty-five IUETs were performed in 26 foetuses. The median gestational age of the first IUET was 22.6 weeks. Only one foetal bradycardia incidence was recorded during the procedure. Three medical pregnancy terminations were observed in our series, secondary to severe cerebral anomalies confirmed in the magnetic resonance imaging. Five in utero deaths occurred, in which 2 of the foetuses underwent multiple IUETs. All the neonates had normal haemoglobin levels at birth, and none were transferred to the neonatal intensive care unit. The overall survival rate was 70%.

CONCLUSION

IUETs exhibit a survival rate similar to that of simple intrauterine transfusions in foetal parvovirus infection cases.

Contribution of fetal brain MRI in management of severe fetal anemia

INTRODUCTION

Intrauterine transfusion (IUT) has changed fetal anemia prognosis. However, long-term neurodevelopmental outcome is altered in 5% of children. Our objective was to study the contribution of fetal MRI to diagnosis brain lesions in case of fetal anemia.

MATERIAL AND METHODS

Retrospective monocentric descriptive study from 2005 to 2016, including all patients followed for fetal anemia requiring IUT. The indications for MRI were: hydrops fetalis and / or hemoglobin <5 g / dL and / or more than 3 IUTs and / or acute severe anemia and / or ultrasound abnormality. Fetal and neonatal outcome and pediatric neurological monitoring were studied.

RESULTS

89 patients were followed for fetal anemia with IUT and 28 (29.1%) had fetal MRI, 12 of which were abnormal. Two out of twelve had abnormal ultrasound. Seven out of twelve had poor neurological prognosis: 2 medical terminations of pregnancy were performed; 2 children had severe developmental delay and 3 children had schooling difficulties. Five out of twelve children had favorable neurological prognosis.

CONCLUSION

MRI of the fetal brain makes it possible to better detect brain lesions than ultrasound does in the management of severe fetal anemia and seems particularly appropriate in cases of acute anemia.

Management of red blood cell alloimmunization in pregnancy

The main cause of fetal anemia is maternal red blood cell alloimmunization (AI). The search of maternal antibodies by indirect antiglobulin test allows screening for AI during pregnancy. In case of AI, fetal genotyping (for Rh-D, Rh-c, Rh-E and Kell), quantification (for anti-rhesus antibodies) and antibody titration, as well as ultrasound monitoring, are performed. This surveillance aims at screening for severe anemia before hydrops fetalis occurs. Management of severe anemia is based on intrauterine transfusion (IUT) or labor induction depending on gestational age. After intrauterine transfusion, follow-up will focus on detecting recurrence of anemia and detecting fetal brain injury. With IUT, survival of fetuses with alloimmunization is greater than 90% but 4.8% of children with at least one IUT have neurodevelopmental impairment.

[Outcome of in utero transfusion in case of fœtomaternal red blood cell incompatibility]

OBJECTIVE

Erythrocyte allo-immunization's rate has decreased but without adapted treatment the prognosis is still poor. The aim of our study was to evaluate the fetal prognosis, the complication's rate and the risk factors of complications of the intrauterine transfusion.

METHODS

Retrospective study about 37 fetus and 86 intrauterine transfusions between 2001 and 2017. Our main criterion in judging was the occurrence of procedure related complications: premature membrane rupture or premature delivery within seven days from the procedure, chorioamnionitis, abnormal fetal heart rate indicating an emergency ceasarean section within the 24hours from the procedure, in utero death or neonatal death related to the procedure.

RESULTS

The survival rate was about 88.9% with a severe complication's rate of 5.8% per intrauterine transfusion and 13.5% per pregnancy. Intrauterine transfusions before 18 weeks of pregnancies was a complication risk factor: 50% of complications before 18 weeks vs. 1.3%, P=0.8×10^-3. On the contrary, hydrops did not seem to be a complication risk factor (16.7% of complication with hydrops vs. 3.9%, P=0.27). The localisation of the needle insertion, intra-abdominal or placental insertion, had no effect on the fetal prognosis.

CONCLUSION

Intrauterine transfusion complications are rare and it enhances the fetal prognosis. However, an early procedure is related to a higher rate of complications.

In utero treatment of severe fetal anemia resulting from fetomaternal red blood cell incompatibility: a comparison of simple transfusion and exchange transfusion

OBJECTIVE

To compare in utero exchange transfusions (IUET) and in utero simple transfusions (IUST) for the treatment of fetal anemia resulting from red blood cell fetomaternal incompatibility.

STUDY DESIGN

Retrospective comparative study from January 2006 through December 2011. The two techniques were compared for effectiveness, complications, and neonatal outcomes.

RESULTS

36 patients had 87 IUETs and 85 patients 241 IUSTs. Gestational age at the first transfusion was similar in both groups (IUET: 27±3.8 weeks; IUST: 27±4.7 weeks; NS) as was the initial fetal hemoglobin level (IUET: 6.4±2.8g/dL; IUST: 6.0±2.5g/dL; NS). No significant differences were noted for postprocedure complications or efficacy. The daily drop in hemoglobin level was similar in both groups (IUET: 0.41±0.23g/dL/day; IUST: 0.44±0.17g/dL/day; NS) as were the time intervals between two procedures. Gestational age at birth was earlier in the IUET group (34.4±1.3 weeks vs 35.5±1.8 weeks; p<0.001), but the postnatal transfusions or exchange transfusions rates and the duration of intensive phototherapy did not differ. No significant differences were noted for the overall survival rates (IUET: 100%; IUST: 96.4%; p>0.99).

CONCLUSION

IUET does not appear to provide any benefits compared with IUST, neither to be associated with a higher complication rate. The choice of the technique depends on availability of packed blood cells with high hematocrit (70-80%).

Severe neonatal anemia from fetomaternal hemorrhage: report from a multihospital health-care system

OBJECTIVE

The incidence of fetomaternal hemorrhage that is severe enough to cause neonatal anemia is not known. Owing to its relative rarity, much of the literature describing this condition is in the form of case reports and small case series. We performed a large, muiticentered, sequential, case series to determine the incidence, antecedents and outcomes.

STUDY DESIGN

From the multicentered databases of Intermountain Healthcare, we obtained records of all neonates with hematocrit (Hct) <30% or hemoglobin (Hgb) <10 g dl(-1) on the day of birth, who had Kleihauer-Betke staining or flow cytometric evidence of fetomaternal hemorrhage.

RESULT

Among 219,853 live births, 24 had anemia with evidence of fetomaternal hemorrhage (incidence estimate, 1 per 9160 live births). The initial Hgb ranged from 1.4 to 10.2 g dl(-1) (Hct 29.8%). The initial Hgb was <7 g dl(-1) in 18 (67%), <5 g dl(-1) in 12 (50%) and was <3 g dl(-1) in 7 (29%). All 7 mothers in whom neonatal Hgb was <3 g dl(-1) had reported absent fetal movement, as did 13 of 18 mothers when the initial Hgb was <7 g dl(-1). Outcomes were poorer in those with the lowest initial Hgb; in the two lowest, one died on day 1, and the other developed a grade 4 intraventricular hemorrhage (IVH). The adverse outcomes of death, IVH, periventricular leukomalacia, bronchopulmonary dysplasia or hypoxic-ischemic encephalopathy were common; occurring in 71% (17 of the 24), including all with an initial Hgb <5 g dl(-1) and all born at ≤35 weeks of gestation.

CONCLUSION

Fetomaternal hemorrhage is a rare but sometimes devastating condition. Those with fetomaternal hemorrhage and an initial Hgb of <5 g dl(-1) are expected to need resuscitation at birth, to receive emergent transfusion support and to be at risk for death and major morbidities. Antenatal suspicion of this diagnosis should occur when absent fetal movement is reported. Improvements in rapid diagnosis are needed to prepare first responders and transfusion services.

Techniques of intrauterine fetal transfusion for women with red-cell isoimmunisation for improving health outcomes

BACKGROUND

Red-cell alloimmunisation can occur when there are incompatibilities between a woman's blood type and that of her unborn baby. This can cause the baby to become anaemic (low red blood cell count), which may require treatment during the pregnancy by blood transfusion while the baby remains within the uterus (called an intrauterine blood transfusion).

OBJECTIVES

To compare, using the best available evidence, the benefits and harms of different techniques of intrauterine fetal blood transfusion for women with red-cell alloimmunisation.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (13 June 2012).

SELECTION CRITERIA

We considered randomised controlled trials comparing different techniques of intrauterine fetal blood transfusion (either alone or in combination with another technique) for inclusion.

DATA COLLECTION AND ANALYSIS

Two authors evaluated trials under consideration for appropriateness for inclusion and methodological quality, without consideration of their results according to the prestated eligibility criteria. We planned to use a fixed-effect meta-analysis for combining study data if we judged the trials to be sufficiently similar. We planned to investigate statistical heterogeneity using the I² statistic; if this indicated a high degree of statistical heterogeneity, we planned to use a random-effects model.

MAIN RESULTS

Our search strategy identified four reports of three studies for consideration, of which two met the inclusion criteria, involving 44 women. We identified a single trial comparing the use of intrauterine fetal blood transfusion and intravenous immunoglobulin versus intrauterine fetal blood transfusion alone, and a single trial comparing the use of atracurium and pancuronium. There were no statistically significant differences identified for any of the reported outcomes.

AUTHORS' CONCLUSIONS

There is little available high quality information from randomised controlled trials to inform the optimal procedural technique when performing fetal intrauterine fetal blood transfusions for women with an anaemic fetus due to red cell alloimmunisation. Further research evaluating the benefits and harms associated with different techniques is required.

Intrauterine transfusion for parvovirus B19 infection: long-term neurodevelopmental outcome

OBJECTIVE

To evaluate long-term neurodevelopmental outcome of children treated with intrauterine transfusions for fetal anemia because of parvovirus B19 infection.

STUDY DESIGN

Children treated with intrauterine transfusions for fetal anemia because of parvovirus B19 infection underwent standardized age-appropriate neurodevelopmental testing. Main outcome was the incidence of neurodevelopmental impairment.

RESULTS

Twenty-eight children were evaluated at a median age of 5 years (range, 1.5-13 years). Neurodevelopmental impairment was diagnosed in 3 of 28 (11%) children, including 1 child with combined cerebral palsy and severe developmental delay and 2 children with isolated severe developmental delay.

CONCLUSION

Neurodevelopmental impairment in children treated with intrauterine transfusion for parvovirus B19 infection is increased compared with the general population. Large long-term follow-up studies are required to determine potential risk factors.

Long-Term follow up after intra-Uterine transfusionS; the LOTUS study

BACKGROUND

The Leiden University Medical Center (LUMC) is the Dutch national referral centre for pregnancies complicated by haemolytic disease of the fetus and newborn (HDFN) caused by maternal alloimmunization. Yearly, 20-25 affected fetuses with severe anaemia are transfused with intra-uterine blood transfusions (IUT). Mothers of whom their fetus has undergone IUT for HDFN are considered high responders with regard to red blood cell (RBC) antibody formation. Most study groups report high perinatal survival, resulting in a shift in attention towards short- and long-term outcome in surviving children.

METHODS/DESIGN

We set up a large long-term observational follow-up study (LOTUS study), in cooperation with the Sanquin Blood Supply Foundation and the LUMC departments of Obstetrics, Neonatology and ImmunoHematology & Bloodtransfusion.The first part of this study addresses several putative mechanisms associated with blood group alloimmunization in these mothers. The second part of this study determines the incidence of long-term neurodevelopment impairment (NDI) and associated risk factors in children treated with IUT. All women and their life offspring who have been treated with IUT for HDFN in the LUMC from 1987-2008 are invited to participate and after consent, blood or saliva samples are taken. RBC and HLA antigen profile and antibodies are determined by serologic or molecular techniques. Microchimerism populations are tested by real time polymerase chain reaction (RT PCR).All children are tested for their neurological, cognitive and psychosocial development using standardised tests and questionnaires. The primary outcome is neurodevelopmental impairment (NDI), a composite outcome defined as any of the following: cerebral palsy, cognitive or psychomotor development < 2 standard deviation, bilateral blindness and/or bilateral deafness.

DISCUSSION

The LOTUS study includes the largest cohort of IUT patients ever studied and is the first to investigate post-IUT long-term effects in both mother and child. The results may lead to a change in transfusion policy, in particular future avoidance of certain incompatibilities. Additionally the LOTUS study will provide clinicians and parents better insights in the long-term neurodevelopmental outcome in children with HDFN treated with IUTs, and may improve the quality of antenatal counselling and long-term guidance.

Techniques of intrauterine fetal transfusion for women with red-cell isoimmunisation for improving health outcomes

BACKGROUND

Red-cell alloimmunisation can occur when there are incompatibilities between a woman's blood type and that of her unborn baby. This can cause the baby to become anaemic (low red blood cell count), which may require treatment during the pregnancy by blood transfusion while the baby remains within the uterus (called an intrauterine blood transfusion).

OBJECTIVES

To compare, using the best available evidence, the benefits and harms of different techniques of intrauterine fetal blood transfusion for women with red-cell alloimmunisation.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (March 2010).

SELECTION CRITERIA

We considered randomised controlled trials comparing different techniques of intrauterine fetal blood transfusion (either alone or in combination with another technique) for inclusion.

DATA COLLECTION AND ANALYSIS

Two authors evaluated trials under consideration for appropriateness for inclusion and methodological quality, without consideration of their results according to the prestated eligibility criteria. We planned to use a fixed-effect meta-analysis for combining study data if we judged the trials to be sufficiently similar. We planned to investigate statistical heterogeneity using the I(2) statistic; if this indicated a high degree of statistical heterogeneity, we planned to use a random-effects model.

MAIN RESULTS

Our search strategy identified four reports of three studies for consideration, of which two met the inclusion criteria, involving 44 women. We identified a single trial comparing the use of intrauterine fetal blood transfusion and intravenous immunoglobulin versus intrauterine fetal blood transfusion alone, and a single trial comparing the use of atracurium and pancuronium. There were no statistically significant differences identified for any of the reported outcomes.

AUTHORS' CONCLUSIONS

There is little available high quality information from randomised controlled trials to inform the optimal procedural technique when performing fetal intrauterine fetal blood transfusions for women with an anaemic fetus due to red cell alloimmunisation. Further research evaluating the benefits and harms associated with different techniques is required.

Fetal anaemia: diagnosis and management

Fetal anaemia can by treated by in-utero therapy, which results in a significant improvement in perinatal outcome. The important causes of fetal anaemia are rhesus alloimmunisation, kell alloimmunisation and parvovirus infection. At-risk pregnancies require serial monitoring to ensure timely intervention with intrauterine transfusion. Non-invasive testing with middle cerebral artery Doppler is becoming the monitoring modality of choice.

An Audit of Outcome in Intravascular Transfusions Using the Intrahepatic Portion of the Fetal Umbilical Vein Compared to Cordocentesis

INTRODUCTION

Maternal red cell alloimmunization is a potential cause of perinatal morbidity and mortality. The outcome of severe disease has been transformed by the use of in-utero and particularly, fetal intravascular transfusion. In the majority of instances this is performed by cordocentesis. However, this cohort study represents the experience in a large tertiary referral centre in performing fetal intravascular transfusions via the intrahepatic vein (IHV).

METHODS

Over an 8-year period, 1997-2004, 221 in-utero transfusions (IUT) were performed for rhesus disease in 66 pregnancies. 86% had severe fetal anaemia caused by anti-D, 10.6% by anti-Kell and 3.4% by anti-c. The median maternal age of the cohort was 31 years (range 19-43). The median gestation at initial IUT was 25 weeks (interquartile range (IQR) 23-29 weeks).

RESULTS

A median number of three IUT were performed in each fetus (IQR 2-5) with a median haemoglobin at first fetal blood sampling of 7.3 g% (IQR 4.6-8.8 g%) (73% < or =5 SD and 27% < or =2 SD). Of the total intravascular transfusions, 170 were performed via the IHV (71.7%), 33 via cordocentesis (13.9%) and 1 by intracardiac puncture (0.5%). There were 'transient' bradycardias complicating 4.1% of all transfusions and amniorrhexis following 1.4%. 92% of babies were live born at a median gestation of 34 weeks (range 21-38) with a birth weight centile of 50 (range 3-90). There was no significant difference in intravascular transfusion complication rate when the procedure was performed via the IHV (7.6%) as compared to cord root puncture (3.0%) (Fisher's exact test, p < 0.47).

CONCLUSION

IUT performed by fetal IHV puncture is safe and carries no excess morbidity when performed for severe rhesus disease.

[Kell alloimmunization in pregnancy]

INTRODUCTION

Kell alloimmunization is a rare disease, although its incidence is the highest after after anti-D alloimmunization.

METHODS

We report two recent cases and a review of the literature to describe practical management of Kell alloimmunization in pregnancy.

DISCUSSION

When an immunization against the Kell antigen was diagnosed, amniocentesis was performed at 14 weeks gestation to determine the fetal blood group. If the fetus was Kell positive, a first fetal blood sample was drawn at 17 weeks gestation in case of fetal hydrops, and at 20 weeks without fetal hydrops. The diagnosis of anemia led to in utero transfusion. A second fetal blood sample was taken at 8 to 10 days, every two weeks during the second trimester and every three or four weeks during the third trimester. Fetal well-being was assessed with weekly sonography and rates of hemoglobin decline. These measures enable adapting the frequency of fetal blood sampling.

Complications of intrauterine intravascular transfusion for fetal anemia due to maternal red-cell alloimmunization

OBJECTIVE

The purpose of this study was to establish the true procedure-related complication rate of intrauterine transfusion therapy.

STUDY DESIGN

A cohort study of 254 fetuses treated with 740 intrauterine blood transfusions for red-cell alloimmunization in a single center in the years 1988 to 2001. Our database was searched for perinatal deaths, emergency deliveries, infections, and preterm rupture of membranes associated with intrauterine blood transfusion. Complications were categorized by two independent obstetricians as procedure-related (PR) or not procedure-related (NPR). Logistic regression analysis was used to identify risk factors for complications.

RESULTS

Overall survival was 225/254 (89%). Fetal death occurred in 19 cases (7 PR) and neonatal death in 10 cases (5 PR). There were two cases of intrauterine infection with Escherichia coli (both PR) and two other cases of preterm premature rupture of membranes (1 PR) within a week of a procedure. Emergency delivery after a transfusion was performed in 18 pregnancies (15 PR). The total PR complication rate was 3.1%, resulting in an overall PR loss rate of 1.6% per procedure. Arterial puncture, transamniotic cord puncture, refraining from fetal paralysis, and advancing gestational age were associated with the occurrence of PR complications.

CONCLUSION

Our study shows that intrauterine transfusion is a safe procedure, with a relatively low PR perinatal loss rate. Arterial puncture and transamniotic cord needling carry a high risk for serious complications, whereas fetal paralysis improves the safety of the procedure. This information on risks of intrauterine transfusion therapy may help to further improve the safety of intrauterine transfusions. Data on complication rates of intrauterine transfusions are essential in counseling patients.

Quantitative determination of anti-K (KEL1) IgG and IgG subclasses in the serum of severely alloimmunized pregnant women by ELISA

BACKGROUND

Severe cases of HDN occur after the immunization of the mother with K (KEL1) antigen. To date, the only means of evaluating the concentration of anti-K in maternal serum is by titration with an indirect antiglobulin test (IAT). A more accurate estimation of the serum anti-K concentration is needed.

STUDY DESIGN AND METHODS

An ELISA technique was developed for the determination of the absolute concentration of anti-K IgG and IgG subclasses in the sera of alloimmunized patients. In this technique, after absorption of anti-K on K-positive RBCs and subsequent elution at acid pH, the concentration of anti-K in the eluate was measured with a sensitive and reproducible ELISA. This method was validated with monoclonal and polyclonal anti-K. It was then used to assay the sera of eight pregnant women with anti-K immunization, associated with early fetal anemia (Hct, 7-17%) detected between the 20th and the 31st week of pregnancy. In addition, in most of these cases, the anemia was associated with fetal hydrops.

RESULTS

The anti-K IgG concentration measured by ELISA in the sera of the eight women varied from 1.0 to 4.1 microg per mL (mean, 2.2 microg/mL). Therefore, severe and early forms of fetal anemia can be observed with a relatively low concentration of anti-K (as compared to the concentration of anti-D in similar cases of fetal anemia due to anti-D). The mean proportion of each IgG subclass of anti-K in these sera was IgG1, 95.9 percent; IgG2, 2.4 percent; IgG3, 1.3 percent; and IgG4, 0.4 percent.

CONCLUSION

A simple method for quantitative estimation of anti-K in human serum has been developed. Low concentrations of anti-K can cause fetal anemia relatively early in pregnancy. This method should lead to a better identification of pregnant women whose fetuses are at risk for severe fetal anemia due to anti-K.

[Management of Rhesus isoimmunization. Viewpoint of the obstetrician]

Although rare, severe forms of Rhesus isoimmunization are still observed. Early diagnosis and treatment with intrauterine transfusions allow an 80% survival rate. Anti-D alloimmunizations usually result from missed prophylaxis with anti-D serum at delivery, thus underlying the need for a rigorous application of this prophylaxis.

Intrauterine Transfusions Affect Fetal T-Cell Immunity

Intrauterine transfusion (IUT) therapy is the treatment of choice in severe hemolytic disease of the fetus. This treatment automatically implies the introduction of alloantigens in the fetal circulation, which might potentially influence the unprimed fetal immune system. The present study provides evidence that the fetal immune system is indeed prone to modulations of the T-cell receptor BV (TCRBV) repertoire as a result of IUT treatment. Most notably, IUT therapy affects the composition of the CD4+ repertoire, whereas this effect may be obscured in the CD8+ subset. The CD8+ subset was found to be influenced by alterations of the TCRBV repertoire both in IUT patients and controls, suggesting that modulations in this subset could be the result of developmental influences. A more detailed analysis on the composition of the individual TCRBV families was performed by evaluating the distribution of the complementarity determining region 3 (CDR3) size lengths of [32P]-radiolabeled TCRBV transcripts. Using this technique, referred to as spectratyping, only marginal changes were observed in the CD4+ and CD8+ subset during the course of treatment and gestational development of both IUT-treated patients and controls. Therefore, the alterations in the overall TCRBV repertoire were of a quantitative rather than a qualitative nature. To evaluate whether the observed alterations in TCRBV usage-frequencies were a reflection of an allo-reactive response, a primed lymphocyte test (PLT) was performed in 3 IUT-treated patients. We observed that IUT, performed as early as 23 weeks of gestation, may induce the establishment of memory T cells against the IUT donor. However, there was no association between the observed changes in TCRBV repertoire and the magnitude of the secondary allo-reactive response.

Intrauterine Transfusions Affect Fetal T-Cell Immunity

Intrauterine transfusion (IUT) therapy is the treatment of choice in severe hemolytic disease of the fetus. This treatment automatically implies the introduction of alloantigens in the fetal circulation, which might potentially influence the unprimed fetal immune system. The present study provides evidence that the fetal immune system is indeed prone to modulations of the T-cell receptor BV (TCRBV) repertoire as a result of IUT treatment. Most notably, IUT therapy affects the composition of the CD4+ repertoire, whereas this effect may be obscured in the CD8+ subset. The CD8+ subset was found to be influenced by alterations of the TCRBV repertoire both in IUT patients and controls, suggesting that modulations in this subset could be the result of developmental influences. A more detailed analysis on the composition of the individual TCRBV families was performed by evaluating the distribution of the complementarity determining region 3 (CDR3) size lengths of [32P]-radiolabeled TCRBV transcripts. Using this technique, referred to as spectratyping, only marginal changes were observed in the CD4+ and CD8+ subset during the course of treatment and gestational development of both IUT-treated patients and controls. Therefore, the alterations in the overall TCRBV repertoire were of a quantitative rather than a qualitative nature. To evaluate whether the observed alterations in TCRBV usage-frequencies were a reflection of an allo-reactive response, a primed lymphocyte test (PLT) was performed in 3 IUT-treated patients. We observed that IUT, performed as early as 23 weeks of gestation, may induce the establishment of memory T cells against the IUT donor. However, there was no association between the observed changes in TCRBV repertoire and the magnitude of the secondary allo-reactive response.

Outcome for children treated with fetal intravascular transfusions because of severe blood group antagonism

OBJECTIVE

To describe the outcome for 92 fetuses treated between May 1987 and January of 1993 with intrauterine (intravascular) transfusions for severe hemolytic disease in comparison with a high-risk and a healthy control group.

STUDY DESIGN

Information on the perinatal period was obtained from the patient records. The children regularly attended the outpatient clinic, and a general pediatric examination was performed on each visit. The psychometer development of the child until age 4 1/2 years was assessed according to Gesell. At the age of 5 years, the adaptation part of the Denver Developmental Screening Test and a Dutch-language test were used. A neurologic examination was performed according to Touwen.

RESULTS

In our study, 77 (83.7%) of 92 fetuses were born alive after intravascular transfusions. The overall survival rate was 79.3%. The follow-up group included 69 infants, with an age range of 6 months to 6 years. Correlation between antenatal and perinatal features showed a significant negative relationship between the number of intrauterine transfusions and the duration of phototherapy (p = 0.002). The probability that neurologic abnormalities would occur was significantly greater when perinatal asphyxia had been present (p < 0.05) and with a lower cord hemoglobin level at birth (p = 0.03). The total number of children with disabilities was 10.1% (7/69).

CONCLUSIONS

The neurodevelopmental outcome for the group of survivors compared favorably with a group of high-risk, very low birth weight infants (10.1% to 18%), and less favorably with a healthy control group (10.1% to 6%).

Polymerase chain reaction determination of RhC, Rhc, and RhE blood types: an evaluation of accuracy and clinical utility

OBJECTIVE

Polymerase chain reaction amplification of a portion of the RhC/c/E/e gene could lead to a rapid, accurate determination of fetal RhC/c/E status. The purpose of this study was to evaluate the accuracy of this technique by testing for the first time a large number of deoxyribonucleic acid samples derived from individuals whose RhC/c/E status was established by standard serologic methods. We also evaluated the potential clinical utility of polymerase chain reaction to ascertain fetal antigen status.

STUDY DESIGN

Samples were obtained from Centre d'Etude du Polymorphisme Humain families used for studies of genetic variation (n = 655). Deoxyribonucleic acid was extracted by standard techniques. With few modifications, published primers and reaction conditions were used. Samples were digested with restriction enzymes yielding characteristic electrophoresis patterns for RhC/c/E. Clinical utility was assessed by review of all patients evaluated for erythrocyte sensitization.

RESULTS

RhC-positive (n = 479), RhC-negative (n = 176), Rhc-positive (n = 524), Rhc-negative (n = 131), RhE-positive (n = 131) and RhE-negative (n = 524) samples were evaluated. The sensitivity of RhC/ c and E typing by polymerase chain reaction was 98.3%, 98.1%, and 96.9%, respectively. The specificity of polymerase chain reaction for identifying the RhC/c/E antigens was 91.5%, 94.7%, and 99.2%, respectively.

CONCLUSIONS

Although it would appear that use of polymerase chain reaction to establish RhC/c/E type could aid in evaluation of RhC/c/E sensitization, we are concerned about the instances of antigen-positive individuals characterized as antigen negative. Further study is necessary to determine if this reflects a polymorphism, mutation, a data coding error, or a combination. The Centre d'Etude du Polymorphisme Humain database is known to contain such errors at a rate that may surpass the error rate of our testing. A second molecular technique could be used to achieve better accuracy in the ascertainment of Rh C/c/E type. On the basis of a review of our patient population, molecular deoxyribonucleic acid techniques now available could aid the management of erythrocyte sensitization in pregnancy in > 96% of cases.

Alterations in cord blood leukocyte subsets of patients with severe hemolytic disease after intrauterine transfusion therapy

OBJECTIVES

The aim of this study was to compare, at delivery, the cord blood mononuclear cells of infants with severe hemolytic disease who received intrauterine transfusion (IUT) therapy with the cord blood mononuclear cells of healthy nonimmunized control neonates.

STUDY DESIGN

The expression of leukocyte markers on CBMNC of 14 IUT-treated and 18 control neonates was analyzed by means of a panel of well-defined monoclonal antibodies and flow cytometry.

RESULTS

Patients with severe hemolytic disease requiring IUT treatment displayed significant altered expression of some leukocyte markers when compared with control subjects. The circulating CD34+ progenitor cells were significantly increased in comparison with cord blood of nonimmunized neonates. IUT-treated patients also showed a statistically significant decrease in natural killer (NK) cell associated markers (CD16, CD57, and CD69), which correlated with a lower expression of CD56. In these patients an increased expression of CD3/CD45RO and CD3/CD5 was also noted. Although these latter alterations were statistically significant in a single-parameter analysis, the significance disappeared after multi-parameter analysis because of a loss of statistical power.

CONCLUSIONS

Compared with nonimmunized healthy newborn infants, patients who underwent IUT also exhibited a down-regulation of NK cells and NK cell associated markers, as well as increased numbers of CD34+ progenitor cells.

Diagnosis and treatment of fetal anemia due to isoimmunization

45 pregnant women affected by rhesus incompatibility were treated at the Department of Prenatal Diagnosis and Therapy, Vienna, between January 1992 and March 1993. 32 patients had a cordocentesis and on 21 fetuses, anemia requiring treatment was diagnosed. A total of 71 intravascular transfusions via the umbilical vein was given. The mean number of transfusions per fetus was 3.4 (range 1-11). Of the 7 fetuses who had already developed hydrops when therapy was started (hematocrit < 13%), 5 (71%) survived. The survival rate of non-hydropic anemic fetuses was 93% (13/14). By using intravascular transfusion for treatment of severe fetal anemia, a success rate of 86% (18/21) was achieved.

PCR-based determination of Rhc and RhE status of fetuses at risk of Rhc and RhE haemolytic disease

After anti-RhD, anti-Rhc is the most important red cell alloantibody which can cause haemolytic disease of the newborn (HDN) when the mother is Rhc-negative and the fetus Rhc-positive. We report here the development of polymerase chain reaction (PCR) assays which detect the presence of the Rhc alleles in amniotic cells by the use of allele-specific primers (ASP). It is expected that such determination will help in the management of pregnancies at risk of Rhc haemolytic disease. In the course of this study we have similarly performed PCR-ASP experiments to detect fetal RHE alleles since, in rare cases, anti-RhE can also cause HDN.

Clinical utility of fetal RhD typing in alloimmunized pregnancies by means of polymerase chain reaction on amniocytes or chorionic villi

OBJECTIVE

Our purpose was to describe the clinical utility of a deoxyribonucleic acid amplification method for determining fetal RhD status in alloimmunized pregnancies

STUDY DESIGN

Six RhD-negative women with alloimmunized pregnancies and heterozygous partners underwent amniocentesis (n = 5) or chorionic villus sampling (n = 1). Fetal RhD type was determined by polymerase chain reaction and results disclosed to the attending physicians.

RESULTS

Knowledge of the fetal RhD status avoided further invasive procedures in two pregnancies and facilitated the timing or performance of intrauterine transfusions in the remainder.

CONCLUSIONS

In alloimmunized pregnancies the ability to RhD-type the fetus in amniotic fluid avoids the risks of fetomaternal hemorrhage and increased sensitization associated with fetal blood sampling or chorionic biopsy. This allows more rational pregnancy management, avoiding invasive procedures in the presence of an RhD-negative fetus, or planning therapeutic interventions or offering termination of pregnancy in the presence of an RhD-positive fetus.

Ultrasound-guided fetal intravascular transfusions for severe erythroblastosis, 1984-1993

The results of the first 10 years' experience in ultrasound-guided fetal intravascular transfusions at the Royal Women's Hospital were reviewed. Since the first transfusion, a variety of techniques have been employed in 78 fetuses, all with severe erythroblastosis. A total of 288 intrauterine transfusions have been attempted with an overall survival rate of 75.6% (59 of 78). The overall survival rate for delivered fetuses improved from 64.3% (18 of 28) in 1984-1987, to 82.0% (41 of 50) in 1988-1993. There was a total of 33 hydropic fetuses, of whom 20 (60.6%) survived, significantly fewer compared with 86.7% (39 of 45) of the nonhydropic fetuses (odds ratio [OR] 0.25, 95% confidence interval [CI] 0.09 to 0.70, p < .01). Fetuses who were sicker at the time of transfusion, as reflected by larger haemoglobin deficits, had lower survival rates, as did those requiring transfusions at earlier gestational ages. When these variables were allowed for, the survival rate significantly improved over time (OR 6.3, 95% CI 1.3 to 30.4, p < 0.05), probably reflecting the increased skill of the ultrasonologists, but the presence of hydrops per se was no longer important. Variations of the technique employed, such as exchange or intraperitoneal transfusion, or different sites for transfusion, were not significantly related to survival.

Prenatal determination of fetal RhD type by DNA amplification

BACKGROUND

An RhD-negative woman whose partner is heterozygous may have preexisting anti-RhD antibodies that may or may not affect a subsequent fetus, depending on whether it is heterozygous. A safe method of determining fetal RhD type early in pregnancy would eliminate the risks to an RhD-negative fetus of fetal-blood sampling or serial amniocenteses.

METHODS

We determined the RhD type in 15 fetuses using the polymerase chain reaction in amniotic cells and serologic methods in fetal blood collected simultaneously. In another 15 fetuses, the RhD type determined from chorionic-villus samples was compared with that identified by typing of DNA from the fetus itself.

RESULTS

RhD typing of DNA from amniotic cells correctly indicated the serologic type in every fetus. Of 10 fetuses with RhD-negative mothers, 4 were identified as RhD-negative and 6 as RhD-positive. Of five fetuses with RhD-positive mothers, four were identified as RhD-positive and one as RhD-negative. There was also complete agreement between the results of RhD typing of DNA from chorionic-villus samples and the results of typing of DNA from fetal tissue. Eleven fetuses were RhD-positive, and 4 were RhD-negative. Four RhD-positive fetuses had RhD-negative mothers. Three RhD-negative fetuses had RhD-positive mothers. There was no contamination by maternal RhD-positive DNA of the samples from RhD-negative fetuses.

CONCLUSIONS

Determining fetal RhD type in amniotic cells without invading the fetomaternal circulation is a reliable method that will be valuable in the management of Rh alloimmunization.

Alloimmune conditions and pregnancy

Transfer of fetal red blood cells and platelets to the maternal circulation can stimulate an immune response with production of immunoglobulin that can cross the placenta. Similarly, passage of maternal stem cells to an immunologically incompetent fetus can theoretically produce graft-versus-host disease. disease. Maternal sensitization to red blood cell antigens such as D and Kell can result in anaemia, hydrops, and death in an incompatible fetus. Current assessment of these pregnancies involves serial analysis of amniotic fluid bilirubin concentration, with umbilical cord blood sampling reserved for special circumstances; neither ultrasound or Doppler blood flow analysis are accurate in the prediction of fetal haematocrit. Intravascular transfusion is the treatment of choice for hydropic fetuses. Perinatal survival in non-hydropic fetuses is similar with either intravascular or intraperitoneal transfusion, and the choice of procedures is individualized. Isoimmune fetal thrombocytopenia is usually the result of maternal sensitization to the PlA1 antigen. There is significant risk of intracranial haemorrhage, both antepartum and during labour and delivery. Umbilical cord blood sampling at term can determine fetal platelet count and the need for platelet transfusion, and can aid in deciding the appropriate route of delivery.

High-dose intravenous IgG for the treatment of severe rhesus alloimmunization

The value of intravenous immunoglobulin (IVIG) in the treatment of 24 severely Rh-sensitized pregnant women was studied. IVIG was infused at a daily dose of 0.4 g/kg maternal body weight for 4-5 consecutive days, and was administered again 15-21 days later until delivery, depending on the evolution of the hemolytic disease. Our population was divided into 3 groups according to the time of onset of therapy: group 1 (n = 8), before 20 weeks' gestation; group 2 (n = 7), 20-28 weeks, and group 3 (n = 9), after 28 weeks. Initial mean anti-D level was significantly higher in group 1 (25.9 +/- 12.9 IU/ml) than in the other 2 groups, whose mean values were, however, higher than 10 IU/ml. Amniotic-fluid total bilirubin levels before the onset of therapy were pathologic, and in 55% of the cases they coincided with zone 3 of Liley's chart. Hydrops fetalis at the onset of treatment accounted for the only 3 fetal deaths in groups 1 and 2. None of the fetuses developed hydrops during treatment. Six of the 9 neonates in group 3 were depressed at birth (1-min Apgar below 7). However, at 5 min only 1 newborn showed an Apgar below 7. Mean birth weight was over 2,500 g in all the cases. Neonatal hematological condition in group 2 (50% of the babies required only phototherapy) was better than in the other 2 groups (transfusional therapy). There was a significant fall in maternal anti-D titers and intrauterine hemolysis after IVIG treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Management of immune haemolytic disease in the fetus

Although Rh alloimmunization has been successfully reduced in frequency and severity since the implementation of Rh immune globulin, cases still occur. The management of affected pregnancies requires the efforts of a team which includes obstetrics/fetal medicine, the blood transfusion service, haematological support, nursing assistance and neonatology. The aim of antenatal management is to predict whether or not the fetus is severely affected, to correct the fetal anaemia and to deliver the baby at the optimal time. The management has improved markedly with the introduction of high-resolution real-time ultrasound, fetal blood sampling, intravascular fetal blood transfusion and/or intraperitoneal transfusion and meticulous fetal surveillance. With appropriate and timely management in severely alloimmunized patient, the survival rate of affected fetuses in some centres is now about 90%. There is still a need for research into new methods of treatment such as high dose intravenous immunoglobulin, which might non-invasively diminish fetal red cell destruction. Due to the reduced frequency of severe disease, regionalized treatment centres are essential in order to maximize the experience and efficiency of the management teams.

[Hydrops fetalis caused by maternal Parvovirus B19 infection]

Maternal infection with human Parvovirus B19 during pregnancy is one of the rare reasons, which can lead to a not immunologically conditioned hydrops fetalis. We report here a case of intrauterine Parvovirus infection associated with hydrops fetalis, diagnosed by intrauterine sonography in the 29 week of gestation, one week after the outbreak of Erythema. The B19 infection of the low birth weight baby, delivered in the 30 week of gestation, was diagnosed serologically with specific IgM and IgG against B19 by ELISA. No malformation could be detected in the liveborn infant, who died on the third day of life.

Intrauterine transfusion--intraperitoneal versus intravascular approach: a case-control comparison

Intravascular fetal transfusion has gained widespread acceptance and has supplanted the use of intraperitoneal fetal transfusion in management of severe alloimmune disease in many centers. This study compares the two methods with regard to multiple objective end points of performance, therapy, and outcome in a highly matched case-control fashion. The intravascular approach is better on almost every level. More surviving infants who are in better condition at a mature gestation and whose mothers have fewer complications and sequelae are the result. Whereas intraperitoneal transfusion should not be abandoned altogether, it is a second-line procedure used only in very limited circumstances. Intravascular fetal transfusion offers realistic prognosis for intact survival at virtually any extreme of alloimmune disease.