Intravascular Transfusion Research Articles

Current clinical management of anti-Kell alloimmunization in pregnancy

Objectives Few reports have been published of the current clinical management of anti-Kell alloimmunization in pregnancy; its low frequency of occurrence means that the few long series published have covered very ample time periods in which different kinds of clinical management have overlapped. The objective of the present paper is to present our experience in the current clinical management of pregnant women who are positive for the anti-Kell antibody. Study design A retrospective analysis was carried out of the case histories of pregnant women who were alloimmunized for the Kell antigen and who were studied and/or treated at the Department of Fetal Medicine in the Virgen de las Nieves University Hospital in Granada (Spain), between 2000 and 2004. The clinical management included the basal measurement of the titre of antibodies, the identification of the paternal phenotype (and that of the fetus, if necessary), the ultrasonographic monitoring of the fetus to detect signs of anaemia, sampling of fetal blood by cordocentesis when fetal anaemia was suspected, and fetal intravascular transfusion when necessary. Results Of the 10 pregnancies with anti-Kell antibodies, The Kell antigen was confirmed in the fetus in three cases, in all of which moderate to severe fetal anaemia developed, requiring fetal intravascular transfusions. Although one of the fetus developed antenatal hydrops, a good perinatal result was advised. Conclusions The current approach to anti-Kell alloimmunization enables pregnant women who have Kell-positive fetuses to be treated successfully.

Successful treatment of fetal erythroblastosis due to anti‐M alloimmunization with fetal intravascular transfusion

Prenatal DiagnosisVolume 27, Issue 4 p. 385-387 Letter to the Editor Successful treatment of fetal erythroblastosis due to anti-M alloimmunization with fetal intravascular transfusion Mee Won Seo, Corresponding Author Mee Won Seo Department of Obstetrics and Gynecology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, KoreaDepartment of Obstetrics and Gynecology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, KoreaSearch for more papers by this authorHye-Sung Won, Hye-Sung Won Department of Obstetrics and Gynecology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, KoreaSearch for more papers by this authorSun-Kwon Kim, Sun-Kwon Kim Department of Obstetrics and Gynecology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, KoreaSearch for more papers by this authorJae-Yoon Shim, Jae-Yoon Shim Department of Obstetrics and Gynecology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, KoreaSearch for more papers by this authorSeog-Woon Kwon, Seog-Woon Kwon Department of Laboratory Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, KoreaSearch for more papers by this authorPil Ryang Lee, Pil Ryang Lee Department of Obstetrics and Gynecology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, KoreaSearch for more papers by this authorAhm Kim, Ahm Kim Department of Obstetrics and Gynecology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, KoreaSearch for more papers by this author Mee Won Seo, Corresponding Author Mee Won Seo Department of Obstetrics and Gynecology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, KoreaDepartment of Obstetrics and Gynecology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, KoreaSearch for more papers by this authorHye-Sung Won, Hye-Sung Won Department of Obstetrics and Gynecology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, KoreaSearch for more papers by this authorSun-Kwon Kim, Sun-Kwon Kim Department of Obstetrics and Gynecology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, KoreaSearch for more papers by this authorJae-Yoon Shim, Jae-Yoon Shim Department of Obstetrics and Gynecology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, KoreaSearch for more papers by this authorSeog-Woon Kwon, Seog-Woon Kwon Department of Laboratory Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, KoreaSearch for more papers by this authorPil Ryang Lee, Pil Ryang Lee Department of Obstetrics and Gynecology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, KoreaSearch for more papers by this authorAhm Kim, Ahm Kim Department of Obstetrics and Gynecology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, KoreaSearch for more papers by this author First published: 29 March 2007 https://doi.org/10.1002/pd.1679Citations: 2AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article.Citing Literature Volume27, Issue4April 2007Pages 385-387 RelatedInformation

High additional maternal red cell alloimmunization after Rhesus- and K-matched intrauterine intravascular transfusions for hemolytic disease of the fetus

Intrauterine transfusion (IUT) is a life-saving therapy for the severely anemic fetus with hemolytic disease. However, maternal additional antibody formation is a complication of the procedure. In this study, we determined antibody formation after introduction of preventive Rh-D, -C, -c, -E, and -e and K matching of IUT donors. This was a retrospective follow-up study. During an 11-year period, 686 Rhesus- and K-matched IUTs were performed in 233 pregnancies and in 95% (652/686) posttransfusion antibody testing was performed after a median interval of 21 days. Twenty-five percent (53/212) of the women formed 64 new antibodies and, compared to our previous study, this incidence was not decreased by the use of Rhesus- and K-matched donors. After delivery, 72% (153/212) of the women had multiple RBC antibodies. Additional antibodies were in 48% (31/64) directed against Rhesus and K antigens, induced by the fetus, or as natural antibodies. In 52% (33/64) the antibodies were directed against non-Rhesus and -K antigens and in 65% (11/17) of eligible cases the IUT donor and not the fetus expressed the corresponding antigen(s). Despite Rhesus- and K-matching, women treated with IUTs still show strikingly broad red cell alloimmunization. More extensive IUT donor red cell matching, including FY, JK, and S antigens, to reduce the formation of new red cell antibodies should be explored.

Long-term neurodevelopmental outcome and brain volume after treatment for hydrops fetalis by in utero intravascular transfusion

Long-term neurodevelopmental outcome and brain volume after treatment for hydrops fetalis by in utero intravascular transfusion

Early intraperitoneal transfusion and adjuvant maternal immunoglobulin in severe alloimmunisation, prior to fetal intravascular transfusion

In this cohort, case series study, we describe the management of 6 pregnancies (in whom a previous pregnancy the fetus has been hydropic and severely anemic prior to 20 weeks gestation associated with a high perinatal mortality (60%)). In the subsequent pregnancy, a treatment regimen of intraperitoneal transfusion from 16 weeks until intravascular transfusion occured at 22 weeks.

Intrauterine intravenous transfusion therapy for hydrops fetalis due to anemia of uncertain causes

The treatment and prognosis of hydrops fetalis depend on the etiology or underlying fetal conditions. Intrauterine transfusions for fetal anemia can be effective in the selected cases [1,2]. Theoretically, anemia of unknown cause, after excluding common lethal problems such as Hb Bart’s disease, is probably justified for intrauterine transfusion. The purpose of the study was to demonstrate the possibility to reverse hydrops fetalis due to fetal anemia of unknown causes with intrauterine intravascular transfusion.

Discordant Fetal Infection for Parvovirus B19 in a Dichorionic Twin Pregnancy

There are only a few reports of fetal parvovirus infection in the circumstance of a twin pregnancy. We report a case of differential fetal infection following maternal parvovirus B19 infection in a dichorionic twin pregnancy culminating in a dual live-birth. A 32-year-old woman was diagnosed with parvovirus infection following exposure to her infected child at 19 weeks' gestation in a dichorionic twin gestation. Maternal IgG seroconversion was documented and maternal blood parvovirus B19 DNA was detected by PCR testing. Fetal monitoring with serial ultrasound assessment was instituted. At 25 weeks' gestation Twin I (male) displayed minor ascites, small pericardial effusion, placentomegaly and oligohydramnios. Middle cerebral artery peak systolic velocity (MCA PSV) studies were abnormal. Twin II (female) was sonographically unremarkable. A single fetal intravascular transfusion for Twin I was performed (pretransfusion Hb 80 g/L). Twin I fetal blood parvovirus B19 DNA was detected by polymerase chain reaction (PCR) and serum demonstrated both B19 IgG and IgM. Following fetal transfusion the hydrops resolved, although the placentomegaly persisted. Two live infants were delivered at 37 weeks' gestation. Individual neonatal venepuncture detected B19 DNA by PCR in Twin I but not in Twin II. B19 IgM was present in Twin I but not Twin II. Both neonates had B19 IgG antibodies. Placental histopathology demonstrated mild edema for Twin I but no inclusion cells. The placenta of Twin II was unremarkable. This case demonstrates the ability for differential transplacental infection of this virus and the assistance of fetal MCA flow studies to guide therapy in a multiple pregnancy at risk of parvovirus infection.

Discordant Fetal Infection for Parvovirus B19 in a Dichorionic Twin Pregnancy

AbstractThere are only a few reports of fetal parvovirus infection in the circumstance of a twin pregnancy. We report a case of differential fetal infection following maternal parvovirus B19 infection in a dichorionic twin pregnancy culminating in a dual live-birth. A 32-year-old woman was diagnosed with parvovirus infection following exposure to her infected child at 19 weeks' gestation in a dichorionic twin gestation. Maternal IgG seroconversion was documented and maternal blood parvovirus B19 DNA was detected by PCR testing. Fetal monitoring with serial ultrasound assessment was instituted. At 25 weeks' gestation Twin I (male) displayed minor ascites, small pericardial effusion, placentomegaly and oligohydramnios. Middle cerebral artery peak systolic velocity (MCA PSV) studies were abnormal. Twin II (female) was sonographically unremarkable. A single fetal intravascular transfusion for Twin I was performed (pretransfusion Hb 80 g/L). Twin I fetal blood parvovirus B19 DNA was detected by polymerase chain reaction (PCR) and serum demonstrated both B19 IgG and IgM. Following fetal transfusion the hydrops resolved, although the placentomegaly persisted. Two live infants were delivered at 37 weeks' gestation. Individual neonatal venepuncture detected B19 DNA by PCR in Twin I but not in Twin II. B19 IgM was present in Twin I but not Twin II. Both neonates had B19 IgG antibodies. Placental histopathology demonstrated mild edema for Twin I but no inclusion cells. The placenta of Twin II was unremarkable. This case demonstrates the ability for differential transplacental infection of this virus and the assistance of fetal MCA flow studies to guide therapy in a multiple pregnancy at risk of parvovirus infection.

Long-term neurodevelopmental outcome and brain volume after treatment for hydrops fetalis by in utero intravascular transfusion

We tested the hypothesis that long-term neurodevelopmental outcomes of successfully treated fetuses with immune hydrops are similar to their unaffected siblings according to a protocol that addresses the underlying pathophysiologic condition. Sixteen of 18 consecutive hydropic fetuses (89%) who were treated in a dedicated fetal medicine unit between July 1985 and October 1995 survived. The transfusion protocol used a 2-step correction over a 2 to 4 day interval, combined with umbilical venous pressure measurements to avoid over transfusion and bicarbonate administration to assure a posttransfusion UV pH of >7.30. Survivors were evaluated at a mean age of 10 years. Statistical analyses included t-test, Wilcoxon rank-sum test, Fisher's exact test, and Pearson coefficients. Overall, death or major neurologic morbidity occurred in 4 of 18 of the fetuses (22%) who were treated (2/16 of survivors [12.5%]). Among the survivors, the children with immune hydrops had physical, neurologic, and cognitive outcomes statistically similar to their siblings, except for a measure of visual attention. Two of the children (12%) had major neurologic sequelae. Brain volumes were statistically smaller than unrelated control subjects by 8.8%, but these control subjects were not matched for height at testing or gestational age at birth. Both groups had brain volumes within the normal range. Intravascular transfusion of fetuses with profoundly anemic immune hydrops results in high survival rates and favorable long-term neuropsychological outcomes.

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% ≤5 SD and 27% ≤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.

The Effects of Serial Intravascular Transfusions in Ascitic/Hydropic RhD-alloimmunized Fetuses

The Effects of Serial Intravascular Transfusions in Ascitic/Hydropic RhD-alloimmunized Fetuses

Long-term neurodevelopmental and neuropsychological outcomes after treatment for immune hydrops fetalis by intravascular transfusion (IVT)

Long-term neurodevelopmental and neuropsychological outcomes after treatment for immune hydrops fetalis by intravascular transfusion (IVT)

P06.03: Discordant fetal infection for parvovirus in a dichorionic twin pregnancy

There are only a very few reports of fetal parvovirus infection in the circumstance of a twin pregnancy. We report a case of differential fetal infection following maternal parvovirus infection in a dichorionic twin pregnancy. A 32-year-old woman was diagnosed with parvovirus infection following exposure to her infected child at 19 weeks’ gestation in a dichorionic diamniotic twin gestation. Maternal seroconversion was documented and parvovirus B19 DNA was present on PCR testing. Fetal monitoring with serial ultrasound assessment was instituted and at 25 weeks gestation Twin I (male) displayed mild ascites, pericardial effusion, placentomegaly and oligohydramnios. The MCA PSV was elevated. Twin II (female) was sonographically unremarkable and the MCA PSV was not elevated. A single fetal intravascular transfusion for Twin I was performed (pretransfusion Hb 80 g/L). Twin I fetal blood was positive for parvovirus B19 DNA and serum demonstrated both IgG and IgM. Following the fetal transfusion the sonographic hydrops resolved, although the placentomegaly persisted. Delivery at 37 weeks’ gestation resulted in live male and female fetuses. Both were vigorous at delivery. Individual neonatal venepuncture showed B19 DNA on PCR to be present in Twin I but absent in Twin II. IgM was present for B19 in Twin I but not Twin II. Both neonates had B19 IgG antibodies, passively acquired from the mother. Histopathology of the placentae demonstrated mild edema in that of Twin I but no inclusion cells. The placenta of Twin II was unremarkable. In conclusion, we present a case of discordant fetal infection in a dizygotic dichorionic twin pregnancy for parvovirus, with a dual live birth at term and no adverse perinatal sequelae. This case demonstrates the ability for differential transplacental infection of this virus and the assistance of MCA flow studies to guide therapy in a multiple pregnancy at risk of parvovirus infection.

Fetal Intravascular Transfusion for Hydropic Disease due to Rhesus Isoimmunization

Objective: To evaluate the management of hydropic fetuses, due to rhesus isoimmunization, with fetal intrauterine intravascular transfusions. Material and Methods: This is a retrospective analysis of 18 rhesus-negative pregnant women presenting at our hospital with fetal hydrops during a 7-year period. All cases were managed with serial intrauterine intravascular transfusions with the goal of delivery by cesarean section beyond 33 weeks of gestation. All patients received prophylactic ampicillin and ritodrine for 4 days after the procedure. Results: There were 11 mildly and 7 severely hydropic fetuses. All fetuses with mild hydrops and 5 of the 7 with severe hydrops were delivered alive after 32 weeks of gestation in a good condition. Two fetuses both with severe hydrops died in utero, at 28 weeks of gestation. Intrauterine reversal of hydrops occurred in 90.9% of fetuses with mild hydrops and in 57.1% of severely hydropic fetuses. Conclusions: The survival rate for the hydropic fetuses in our study was 88.9% and it was associated with the severity of fetal hydrops.

Transfusión intravascular fetal en el tratamiento de la isoinmunización

Objective To assess perinatal outcome after fetal intravascular transfusion in the treatment of alloimmunization between 1990 and 2003. Subjects and methods Fetal blood sampling was offered to immunized pregnant women when significant fetal anemia was suspected. Intravascular fetal transfusion was performed when the fetal hematocrit was below –2 standard deviations for gestational age. Serial transfusions were scheduled every 3 weeks until approximately 34-35 weeks. Results Cordocentesis was performed in 32 singleton pregnancies. In 11 (34%) of these, no fetal anemia as defined by the established criteria was detected. Fifty intravascular fetal transfusions were performed in 19 pregnancies, from the 21st to the 35th week. No spontaneous fetal losses were observed. At 0-13 years of age, all the children showed normal development for their age. Conclusion Fetal intravascular transfusion is an effective procedure in the prenatal treatment of fetal anemia with favorable long-term outcome.

The effects of serial intravascular transfusions in ascitic/hydropic RhD‐alloimmunized fetuses

To evaluate the effects of serial intravascular transfusions on RhD-alloimmunized fetuses with ascites/hydrops at the time of the first transfusion by measuring multiple hematological/biochemical blood variables. Thirty-one singleton pregnancies were referred for management of RhD alloimmunization. Seven fetuses had hydrops on presentation and were transfused immediately. The remainder underwent weekly ultrasound examinations, and fetal blood sampling and transfusion were performed on development of ascites. In the 104 samples collected overall from the 31 fetuses, glucose, uric acid, urea, creatinine, total protein, total and direct bilirubin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyltransferase, alkaline phosphatase, lactic dehydrogenase, amylase, pseudocholinesterase (PCHE), creatine kinase, triglycerides and cholesterol were measured and compared with a reference range for non-anemic fetuses. The median gestational age at first transfusion was 26 (range, 18-34) weeks. There were three fetal losses after the first transfusion, two of which were due to procedure-related complications; one further loss occurred. At the first transfusion fetal hematocrit, pO2, total protein, PCHE, creatinine and urea concentrations were significantly decreased compared to reference data, while total and direct bilirubin, AST, ALT, amylase, triglyceride and uric acid concentrations were increased. In all surviving fetuses ascites/hydrops had disappeared by the second transfusion. Fetal pO2, total protein, AST, ALT and PCHE concentrations had normalized by the third transfusion. Correction of fetal anemia did not affect the other variables. RhD-alloimmunized fetuses with ascites/hydrops at the time of the first transfusion had a survival rate of 87%. Alterations of several biochemical fetal blood indices are present at the first sampling/transfusion, but most variables normalize with intravascular transfusions.

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

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

Treatment of fetal anemia due to red-cell alloimmunization with intrauterine transfusions in the Netherlands, 1988-1999.

To assess pregnancy outcome after intrauterine transfusion (IUT) for fetal anemia due to red-cell alloimmunization in the Netherlands over 11 years, in order to improve care and counseling. A retrospective cohort study was conducted from January 1, 1988, to January 1, 1999. Data were collected prospectively on all red-cell alloimmunized pregnancies requiring intrauterine blood transfusions. Primary outcome variables were fetal and neonatal survival in relation to the type of antibody, gestational age and presence or absence of hydrops. In addition, we studied short-term neonatal morbidity and procedure-related complications. A total of 210 fetuses from 208 pregnancies received 593 transfusions. Overall survival rate was 86%. Survival of hydropic fetuses (78%) was significantly different from those without hydrops (92%). Low survival rates were especially found in hydropic fetuses with the first transfusion at gestational ages of 20 weeks or less (55%) or between 28 and 32 weeks (59%). In maternal rhesus D [Rh(D)] immunization 89% of fetuses survived, whereas survival in the case of Kell immunization was 58%. All fetuses with anemia due to Rh(c) immunization survived. The overall fatal procedure-related complication rate was 1.7% per procedure, resulting in a fetal loss rate of 4.8%. Intrauterine intravascular transfusions are effective in the management of fetal alloimmune anemia. Fetal hydrops, mostly associated with late referral, decreases the chance of survival. To improve the outcome of red-cell alloimmunized pregnancies early diagnosis of fetal anemia and referral to a specialized center are important, enabling the start of treatment before hydrops develops.

Relation of ANP and BNP to their N-terminal fragments in fetal circulation: evidence for enhanced neutral endopeptidase activity and resistance of BNP to neutral endopeptidase in the fetus.

To investigate the role of neutral endopeptidase in the turnover of atrial (ANP) and brain (BNP) natriuretic peptides and their N-terminal fragments in human fetal circulation. Retrospective case-control study. Department of Obstetrics and Gynaecology, University of Leipzig, Germany. Nine control pregnancies and nine pregnancies with rhesus isoimmunisation before and after intravascular transfusion. Natriuretic peptides and N-terminal fragments in maternal and fetal blood were measured by radio-immunoassay. Neutral endopeptidase activity was determined by HPLC. Maternal and fetal plasma concentrations of ANP, NT-proANP, BNP, NT-proBNP as well as neutral endopeptidase activity. Ratios between mature peptide and N-terminal fragment. Feto-maternal ratio. Plasma NT-proANP concentrations are 11.7 times higher in fetal than in maternal circulation. The ANP concentration is only 1.8 times higher, probably due to doubled neutral endopeptidase activity. In contrast, both NT-proBNP and BNP are doubled in fetal plasma. Fetuses with Rh isoimmunisation had significantly higher NT-proBNP but not NT-proANP and neutral endopeptidase activity than controls. An additional volume load by intravascular transfusion did not influence N-terminal fragments or neutral endopeptidase activity. Our study is the first to determine NT-pro natriuretic peptide concentrations and neutral endopeptidase activity in human fetuses. The results show that increased fetal neutral endopeptidase activity shifts the ANP/NT-proANP but not the BNP/NT-proBNP ratio and that the shifted BNP/NT-proBNP ratio in fetuses with Rh isoimmunisation does not involve increased neutral endopeptidase activity. These findings point to a BNP degradation that is not dependent on neutral endopeptidase.

Sonographic demonstration of brain injury in fetuses with severe red blood cell alloimmunization undergoing intrauterine transfusions.

To assess sonographically brain anatomy in fetuses with severe anemia due to red blood cell alloimmunization undergoing intrauterine intravascular transfusions. Multiplanar neurosonography was performed in seven consecutive hydropic fetuses undergoing intrauterine transfusions (mean gestational age 22 +/- 2.5 weeks; mean hemoglobin concentration at the first transfusion 2.3 +/- 1.0 g/dL). Abnormal cerebral findings were identified in four out of seven fetuses. An intracerebellar hemorrhage developed in two fetuses after the first transfusion and one fetus that had severe brain edema before the first transfusion was later found to have cystic periventricular leukomalacia. In one fetus unilateral ventriculomegaly was noted after the first transfusion. Two fetuses were terminated. The remaining pregnancies had an uneventful course, the infants were delivered between 34 and 36 gestational weeks and were alive and well at the time of writing. Prenatal diagnosis of brain injury was always confirmed except for the case with ventriculomegaly that underwent spontaneous intrauterine resolution. Fetuses with extreme anemia due to red blood cell alloimmunization can be salvaged by intrauterine transfusion. In some of these cases brain injury may occur prenatally, and the risk seems to be particularly high when the hemoglobin concentration at the time of the first transfusion is <or= 2 g/dL. We suggest that in these pregnancies detailed fetal neuroimaging by either multiplanar sonography and/or magnetic resonance imaging is indicated.