Complex Modes of Inheritance in Hereditary Red Blood Cell Disorders: A Case Series Study of 155 Patients

Hereditary erythrocytes disorders include a large group of conditions with heterogeneous molecular bases and phenotypes. We analyzed here a case series of 155 consecutive patients with clinical suspicion of hereditary erythrocyte defects referred to the Medical Genetics Unit from 2018 to 2020. All of the cases followed a diagnostic workflow based on a targeted next-generation sequencing panel of 86 genes causative of hereditary red blood cell defects. We obtained an overall diagnostic yield of 84% of the tested patients. Monogenic inheritance was seen for 69% (107/155), and multi-locus inheritance for 15% (23/155). PIEZO1 and SPTA1 were the most mutated loci. Accordingly, 16/23 patients with multi-locus inheritance showed dual molecular diagnosis of dehydrated hereditary stomatocytosis/xerocytosis and hereditary spherocytosis. These dual inheritance cases were fully characterized and were clinically indistinguishable from patients with hereditary spherocytosis. Additionally, their ektacytometry curves highlighted alterations of dual inheritance patients compared to both dehydrated hereditary stomatocytosis and hereditary spherocytosis. Our findings expand the genotypic spectrum of red blood cell disorders and indicate that multi-locus inheritance should be considered for analysis and counseling of these patients. Of note, the genetic testing was crucial for diagnosis of patients with a complex mode of inheritance.

Neonatal hereditary spherocytosis caused by a de novo frameshift mutation of the SPTB gene characterized by hydrops fetalis: A case report

RATIONALE

The etiology of non-immune hydrops fetalis is complex, and its prognosis is poor. One of its main causes is anemia. There are few reports on hydrops fetalis due to anemia caused by hereditary spherocytosis (HS), especially regarding its occurrence in the neonatal period. Thus, we report on a case of neonatal HS caused by a new SPTB gene mutation that was characterized by hydrops fetalis.

PATIENT CONCERNS

A neonate with intrauterine hydrops fetalis showed severe hyperbilirubinemia and anemia, reticulocytosis, and hepatosplenomegaly. Laboratory examination findings were normal.

DIAGNOSES

Gene sequencing of the patient and his parents showed a de novo frameshift mutation in the patient's SPTB gene. Ultimately, the patient was diagnosed with HS.

INTERVENTIONS

Exchange and red blood cell transfusions were performed in the neonatal period.

OUTCOMES

The child was discharged from the hospital 14 days postnatal because his hemoglobin and bilirubin levels were stable. Red blood cell transfusion was performed once in infancy; however, no further red blood cell transfusions were required within 2 years of age.

LESSONS

Hydrops fetalis can be a manifestation of HS. Genetic detection can help confirm the diagnosis of suspected neonatal HS undocumented by other laboratory examinations.

Recurrent fetal hydrops with maternal M alloimmunisation: not a benign condition

Haemolytic disease of the fetus and newborn (HDFN) is associated with red cell antibodies. Anti-M usually results in a mild haemolysis and is rarely clinically significant. There is no established consensus on management of pregnancies with anti-M. A case of recurrent HDFN with maternal M alloimmunisation was identified at a tertiary hospital in Australia. We collected the patient and neonate's clinical and pathological data and interpreted the case with available literature. This is the first case in literature of recurrent fetal hydrops in the setting of M alloimmunisation. Neonate was delivered in a poor condition, intubated and admitted to the neonatal intensive care unit for ionotropic support, red cell transfusion and plasma transfusion for coagulopathy. Direct Coombs test was positive, confirming HDFN. Although anti-M rarely causes HDFN, accurate history, fetal surveillance and monitoring is essential for identification of fetal anaemia. Concurrent placental disease may increase fetal risk from anti-M antibodies.

Molecular characteristics of thalassemia and hemoglobin variants in prenatal diagnosis program in northern Thailand

Molecular analysis of globin genes is an essential process for prenatal diagnosis (PND) of severe thalassemia. This study aimed to describe the molecular characteristics of thalassemia and hemoglobin (Hb) variants in PND program in northern Thailand. The type and frequency of globin gene mutations from 1290 couples at risk of fetal severe thalassemia diseases that were tested at Thalassemia Laboratory at Chiang Mai University from 2012 to 2017 were retrospectively reviewed. The PND program detected 444 (34.4%), 196 (15.2%) and 642 (49.8%) couples at risk of fetal Hb Bart's hydrops fetalis, beta-thalassemia major (BTM) and beta-thalassemia/Hb E disease, respectively. Coinheritance of more than one type of thalassemia was common and eight (0.6%) couples were at risk of two types of severe thalassemia. There were two types of alpha⁰-thalassemia; 893 (99.7%) Southeast Asian and 3 (0.3%) Thai deletions. Twenty beta-globin gene mutations were found with 94.3% of beta⁰-thalassemia. The codon 41/42 (- TTCT), codon 17 (A>T), IVS-I-1 (G>T) and codon 71/72 (+ A) comprised 90% of beta-thalassemia mutations. The study shows a high percentage of couples at risk of fetal Hb Bart's hydrops fetalis and BTM. The percentage of beta⁰-thalassemia is higher than those seen in other regions of Thailand.

Importance of the Average Glucose Level and Estimated Glycated Hemoglobin in a Diabetic Patient with Hereditary Hemolytic Anemia and Liver Cirrhosis

Glycated hemoglobin (HbA1c) is a widely used marker of glycemic control but can be affected by hemolytic anemia. Glycated albumin (GA) is also affected in patients with liver cirrhosis. We herein report the assessment of glycemic control in a 41-year-old man with dehydrated hereditary stomatocytosis and a PIEZO1 gene mutation complicated by diabetes mellitus and liver cirrhosis due to hemochromatosis. The estimated HbA1c calculated from the average glucose level obtained by continuous glucose monitoring or by self-monitoring of blood glucose was useful for evaluating the glycemic control in this patient, as HbA1c and GA were unreliable due to the coexisting conditions.

Anti-M induced severe haemolytic disease of foetus and newborn in a Malay woman with recurrent pregnancy loss

Haemolytic disease of the foetus and newborn (HDFN) is caused by maternal red blood cells (RBC) alloimmunisation resulted from incompatibility of maternal and foetal RBCs. However, only a few HDFN attributed to anti-M were reported, varying from asymptomatic to severe anaemia with hydrops foetalis and even intrauterine death. A case of severe HDFN due to anti-M alloantibody from an alloimmunized grandmultiparous Malay woman with recurrent pregnancy loss is reported here. The newborn was delivered with severe and prolonged anaemia which required frequent RBC transfusions, intensive phototherapy and intravenous immunoglobulin administration. Although anti-M is rarely known to cause severe HDFN, a careful serological work-up and close assessment of foetal well-being is important, similar to the management of RhD HDFN. Alloimmunisation with anti-M type can lead to severe HDFN and even foetal loss.

Management and Outcomes of Fetal Hydrops in a Tertiary Care Centre in Singapore

Introduction: Fetal hydrops is a serious condition which can be caused by immune and non-immune aetiologies. We aimed to review the management of fetal hydrops at our hospital. Materials and Methods: A retrospective review of all cases of fetal hydrops diagnosed in our institution from 2006 to 2013 was carried out. Results: Out of the 30 cases of fetal hydrops diagnosed antenatally, 17 were cases of Bart's hydrops which were all terminated in-utero. Of the remaining 13 cases, 11 cases consisted of non-immune causes of hydrops. Planned antenatal interventions including in-utero blood transfusions (n = 4) and thoracentesis (n = 5) as well as planned caesarean deliveries (n = 11) were performed in the majority of cases. Postnatal neonatal intensive care with interventions including chest drainage and transfusions were also performed. A majority, 92%, of the cases survived the perinatal period following a variable length of hospital stay ranging from a week to 3 months. Conclusion: Management of fetal hydrops is complex. Close coordination between the obstetric and neonatal teams was the key to good short-term survival of neonates with antenatally diagnosed hydrops, as it allows timely antenatal intervention and anticipation of potential perinatal complications.

Cholestasis in infants with immune hydrops fetalis

Rhesus (Rh) hemolytic disease of the newborn represents a broad spectrum of symptoms in the fetus and newborn, ranging from mild to severe hemolytic anemia and hydrops fetalis. Cholestasis is a common problem in infants with immune hydrops fetalis (IHF). The aim of this study was to evaluate the incidence and course of cholestasis in infants with IHF due to Rh alloimmunization. Infants with IHF during the 10-year follow-up were retrospectively included in the study. Demographics, laboratory parameters, and prenatal and postnatal interventions were recorded. The incidence of cholestasis and certain risk factors were investigated. A total of 30 infants with IHF with a mean gestational age 33 ± 2.6 weeks were included. Of these, 15 infants (50%) survived to discharge. The incidence of cholestasis was 60% (18/30). Cholestasis was diagnosed within a median 3 (0-7) days. All cholestatic infants who survived recovered within three months. In conclusion, cholestasis in IHF is frequent, transient and has an early onset.

Hemolytic disease of the fetus and newborn with late-onset anemia due to anti-M: a case report and review of the Japanese literature

Hemolytic disease of the fetus and newborn (HDFN) attributed to M/N-incompatibility varies from asymptomatic to lethally hydropic. Case reports are rare, and the clinical significance of anti-M is not completely understood. A challenging case of HDFN due to anti-M prompted an investigation of the Japanese literature, in order to characterize the clinical spectrum of M/N-incompatibility pregnancies in Japan and report results to English-language readers. Japanese reports of HDFN attributed to M/N incompatibility were compiled. Abstracted data include maternal antibody titers at delivery, fetal direct antiglobulin test, hemoglobin, total bilirubin, reticulocyte count at birth, and therapeutic interventions. We investigated characteristics of HDFN due to M/N-incompatible pregnancies in Japan after encountering a case of severe HDFN along with late-onset anemia in an infant born to a woman carrying IgG anti-M with a titer of 1. In total, thirty-three babies with HDFN due to anti-M and one due to anti-N have been reported in Japan since 1975. The median maternal antibody titer was 64 at delivery and was 16 or less in 10 of 34 women (29%). Five of 34 babies (15%) were stillborn or died as neonates. Twenty-one of 29 survivors (72%) had severe hemolytic anemia and/or hydrops fetalis. The reticulocyte count of neonates with anemia stayed below the reference interval. Sixteen (55%) developed late-onset anemia and 14 (48%) were transfused with M-negative RBCs. Significant positive correlation (P < .05) between the hemoglobin value and the reticulocyte count within 4 days of birth was obtained in 16 babies with anti-M HDFN. In the Japanese population, 21 of 34 cases of M/N-incompatible HDFN (72%) have manifested as severe hemolytic anemia and/or hydrops fetalis. Low reticulocyte count in neonates with late-onset anemia is consistent with suppressed erythropoiesis due to anti-M.

Angiogenic and antiangiogenic factors before and after resolution of maternal mirror syndrome

Mirror syndrome is a rare condition that involves fetal hydrops, placentomegaly and severe maternal edema. The pathogenesis of this syndrome mimics endothelial dysfunction observed in pre-eclampsia. We report a case of maternal mirror syndrome caused by bilateral fetal hydrothorax that resolved after intrauterine pleuroamniotic shunt placement. At the time of the clinical manifestation there was an antiangiogenic state similar to that seen in pre-eclampsia, which resolved after fetal treatment. Our findings suggest that mirror syndrome is a manifestation of a broad spectrum of pathological conditions that induces an antiangiogenic state.

Management of foetal hydrops secondary to Kell isoimmunisation via foetal blood transfusion: a Doppler-guided approach

We describe a male neonate with foetal hydrops due to foetal anaemia caused by Kell isoimmunisation. The severity of anaemia was monitored by Doppler ultrasonography of the middle cerebral artery peak systolic velocity, and this was used to time the foetal blood transfusions. The 33-year-old Indian mother received a total of five foetal blood transfusions from 21 weeks to 31 weeks of gestation, resulting in resolution of the anaemia and hydrops.

Nonimmune Hydrops Fetalis Diagnosed during the Second Half of Pregnancy in Southern China

OBJECTIVE

To analyze the etiologies of nonimmune hydrops fetalis (NIHF) for a southern section of China.

METHODS

138 cases of NIHF presenting after 20 weeks' gestation over a 10-year period were reviewed.

RESULTS

The causes of fetal hydrops were identified in 92.0%. Homozygous alpha-thalassemia dominated as the cause of NIHF (55.1%), followed by infection (15.2%) and structural abnormalities (10.9%). No obvious cause was identified in 11 cases (8.0%). Termination of pregnancy was performed in 131 cases.

CONCLUSIONS

Homozygous alpha-thalassemia is the most common cause of NIHF in southern China. An effective prenatal thalassemia screening program should be established in this high prevalence region.

Long-term effects of a midgestational asphyxial episode in the ovine fetus

We and others have shown previously that fetuses at midgestation can survive 30 min of complete umbilical cord occlusion, although hydrops fetalis (or gross fetal edema) results. To investigate whether this hydrops resolves by late gestation and if there are any long-term consequences of the asphyxial insult on the heart and kidneys, eight fetuses were subjected to 30 min of complete umbilical cord occlusion at 0.6 gestation (90 days; term 150 days) and were compared to a sham group (n = 10). During the occlusion period, fetuses became severely hypoxemic, hypercapnemic, and acidotic, with both blood pressure and heart rate decreasing. Most variables had returned to normal by 2-hr recovery. At 129 +/- 1 days of gestation, approximately 40 days post occlusion, some fetuses were still slightly hydropic as skin fold measurements were increased (P < 0.01), although fetal body weight was not different from the sham group. The two groups had similar heart and kidney weights, ventricular cardiac myocyte nucleation, and glomerular number. By contrast, brain weight was reduced by 37% (P < 0.001) and the cerebral lateral ventricles were grossly dilated. Lungs were 50% smaller than in sham fetuses (P < 0.001). Thus, the hydrops that develops at midgestation as a result of a severe asphyxial episode can, but does not always, fully resolve by late gestation. Also, while fetuses at midgestation can survive this asphyxial episode with no long-term impact in renal or cardiac size, nephron number, or cardiomyocyte nucleation, the brain and lungs are severely affected.

An increase of the cardiothoracic ratio leads to a diagnosis of Bart's hydrops

BACKGROUND

Thalassemia is a common single gene disorder in Southeast Asia. a-thalassemia is a group of syndrome characterized by deficient production of the alpha-globin chain. Individuals with heterozygous alpha-thalassemia-1 are at risk of having a fetus that has Hemoglobin Bart's hydrops fetalis (Hb Bart's). Usually, when the hemoglobin electrophoresis in heterozygous alpha-thalassemia-1 is normal, the Mean Corpuscular Volume (MCV) is lowered. We report a case of increased cardiothoracic ratio that led to a diagnosis of Hb Bart's in a couple who had normal hemoglobin electrophoresis and low MCV.

CASE REPORT

A 23-year-old woman, gravida 2, Para 0-0-1-0, initially presented for antenatal care at 13 weeks pregnancy. Her MCV was 67 fentolitre, DiChlorophenol-IndolPhenol (DCIP) test was negative and hemoglobin electrophoresis was normal. Her husbands MCV was 67 fentolitre, and hemoglobin electrophoresis was normal. Cardiomegaly (an increased of the cardiothoracic ratio) was detected by ultrasonogram at 25 weeks of gestation. She and her husband were comprehensively counseled after an Hb Bart's was suspected. A cordocentesis was performed and the fetal blood was tested for hemoglobin electrophoresis. The result was later known and confirmed as Hb Bart's. The couple decided to terminate the pregnancy. The induced abortion was successful and the patient was discharged on the second day after the abortion. She was well at the 4-week follow-up.

CONCLUSION

A prenatal ultrasonographic screening should be conducted in couples who are suspected of being alpha-thalassemia-1 carriers when DNA study of alpha-globin gene cannot be performed. The increase of cardiothoracic ratio will help detect an early stage of Hb Bart's.

Rapid and cost-effective antenatal diagnosis of haemoglobin Bart's hydrops foetalis syndrome using a duplex-polymerase chain reaction

Haemoglobin Bart's hydrops foetalis syndrome (--SEA/--SEA) is not compatible with life and contributes to a majority of the hydropic foetuses in the Malaysian Chinese alpha-thalassaemia carriers who possess the 2-alpha-gene deletion in cis (--SEA/alphaalpha). A duplex-PCR which simultaneously amplifies a normal 136 bp sequence between the psialpha-alpha2-globin genes and a 730 bp Southeast Asian deletion-specific sequence (--SEA) between the psialpha2-theta1-globin genes was established. The duplex-PCR which detects the --SEA deletion in both chromosomes serves as a rapid and cost-effective confirmatory test in the antenatal diagnosis of Haemoglobin Bart's hydrops foetalis syndrome in Malaysia. In addition, the duplex-PCR is simple to perform as both the normal and deletion-specific alpha-globin gene sequences are amplified in the same PCR reaction.

ABO incompatibility due to immunoglobulin G anti-B antibodies presenting with severe fetal anaemia

ABO incompatibility is a common haematological problem affecting the newborn. The haemolysis is widely accepted to follow a relatively benign course rarely causing the escalating levels of hyperbilirubinaemia and significant anaemia associated with Rh haemolytic disease of the newborn. Case reports of fetal hydrops secondary to ABO incompatibility are particularly rare. We describe two cases, first that of a twin pregnancy with both fetuses developing severe anaemia at 20 weeks gestation, and then a second case of a preterm baby demonstrating aggressive haemolysis and anaemia within hours of delivery. Both mothers were of black Africian origin and both were identified to have elevated titres of IgG anti-B antibodies.

Hemoglobin H hydrops fetalis syndrome resulting from the association of the - -SEA deletion and the alphaQuong Szealpha mutation in a Chinese woman

A case with Hb H hydrops fetalis syndrome resulting from the association of the - -(SEA) deletion and the alpha(Quong Sze)alpha mutation is reported. This is the first description of Hb H hydrops associated with the Hb Quong Sze mutation.

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

OBJECTIVE

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.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

Simple non-invasive prenatal detection of Hb Bart's disease by analysis of fetal erythrocytes in maternal blood

OBJECTIVE

To investigate a simple non-invasive technique for early detection of Hemoglobin (Hb) Bart's disease.

METHOD

Maternal blood smears from 8 known Hb Bart's pregnancies and 40 at-risk pregnancies were investigated. Maternal peripheral blood smears were stained with fluorescence-labeled monoclonal antibodies against alpha- and embryonic zeta-globin chains.

RESULTS

Fetal nonnucleated red blood cells, stained with anti-zeta but not with anti-alpha globin antibodies were found in 15 out of 16 affected pregnancies but were not detected in 23 out of 24 unaffected pregnancies.

CONCLUSION

Results showed that non-invasive immunofluorescence staining of maternal blood is a feasible approach for screening Hb Bart's disease before ultrasound manifestation in affected pregnancies.

Hydrops fetalis associated with homozygosity for hemoglobin Taybe (alpha 38/39 THR deletion) in newborn triplets

Hemoglobin Taybe is an unstable alpha-chain hemoglobin variant caused by a deletion of a threonine residue at codon 38 or 39 of the alpha-1 globin chain. We describe preterm infant triplets born with hydrops fetalis and anemia who were found by DNA analysis to be homozygous for hemoglobin Taybe. All three infants developed intrauterine hemolytic anemia, which subsequently led to hydrops fetalis. To the best of our knowledge, this is the first description of hydrops fetalis associated with this hemoglobinopathy. We suggest that hemoglobin Taybe be considered in the differential diagnosis of hydrops fetalis and that known affected fetuses be carefully followed both antenatally and postnatally.

Co-inheritance of Hb Pak Num Po, a novel alpha1 gene mutation, and alpha0 thalassemia associated with transfusion-dependent Hb H disease

Hb H disease is generally associated with moderate to severe anemia but rarely requires regular blood transfusion. We recently studied two apparently unrelated patients with transfusion-dependent Hb H disease. Hemoglobin studies demonstrated Hb H and Hb Bart's without other detectable abnormal globin species. Extensive molecular analyses of the alpha globin genes and their regulatory sequence (HS-40) revealed that both patients are compound heterozygotes for alpha0 thalassemia (--(SEA)) and a novel point mutation, a thymidine insertion after codon 131 of the alpha1 gene. The resulting frameshift gives rise to a highly unstable alpha globin chain, which we refer to as "Hb Pak Num Po," containing an additional 34 amino acids. This unusual alpha1 globin variant clearly causes alpha thalassemia, but the unexpectedly severe phenotype suggests that this mutation may have additional effects on red cell physiology. A PCR-based (ARMS) assay was developed for rapid detection of this novel mutation, and this might be useful to study the prevalence of this novel mutation which poses potentially significant clinical consequences in populations of Southeast Asia. Detecting carriers of this mutation using the molecular diagnostic procedures described will provide the means to screen and prevent a potentially severe form of alpha thalassemia in Thailand.

The expanding spectrum of disorders with elevated plasma chitotriosidase activity: an update

A striking elevation of plasma chitotriosidase activity, greater than 150 times the normal median value, was found in two galactosialidosis patients. Furthermore, increased plasma chitotriosidase activity, 10-53 times the normal median value, was also observed in fucosidosis, glycogen storage disease type IV, Alagille syndrome and hydrops fetalis due to congenital herpes virus infection.

Long term follow up of serostatus after maternofetal parvovirus B19 infection

BACKGROUND

Maternofetal parvovirus B19 infection may result in fetal hydrops or abortion. Chronic infection has been associated with long term complications (polyarthritis, persistent aplastic anaemia, hepatitis). In pregnancy maternal immunosuppression caused by a TH2 dominant response to viral antigens has been observed. There is little information on long term reactivity to intrauterine infection.

AIMS

To assess the serological status in children and their mothers after maternofetal parvovirus B19 infection and development of fetal hydrops.

METHODS

A total of 18 children and their mothers, and 54 age matched control infants were studied. Main outcome measures were parvovirus B19 DNA, specific IgM and IgG against the virus proteins VP1/VP2, and NS-1 in venous blood.

RESULTS

Parvovirus B19 DNA and antiparvovirus B19 (IgM) were undetectable in all sera. A significant larger proportion of maternal sera compared to study children's sera contained IgG against the non-structural protein NS-1. Mean levels of VP1/VP2 IgG antibodies were significantly lower in the children than in their mothers (48 (36) v 197 (95) IU/ml). There was no history of chronic arthritis in mothers and children. Five women had subsequent acute but transient arthritis postpartum, which was not correlated with antibodies against NS-1.

CONCLUSIONS

Serological evidence of persistent infection after maternofetal parvovirus B19 disease could not be detected. Increased maternal prevalence of anti NS-1 (IgG) and increased levels of antiparvovirus B19 (IgG) may reflect prolonged viraemia compared to fetal disease.

A new method to determine the feto-placental volume based on dilution of fetal haemoglobin and an estimation of plasma fluid loss after intrauterine intravascular transfusion

OBJECTIVES

(1) To calculate the feto-placental volume (FPV), using the haematocrit (Ht) values and the percentages of fetal haemoglobin (HbF), before and after red blood cell transfusion. (2) To estimate the transfusion-induced loss of plasma fluid.

DESIGN

Retrospective analysis of data of 42 anaemic fetuses at the first transfusion [gestational age (GA) 19-36 weeks].

SETTING

Department of Obstetrics, Leiden University Medical Centre, The Netherlands.

SAMPLE

Fifteen hydropic and 27 non-hydropic fetuses.

METHODS

Donor blood volume (V(donor)) and Ht (Ht(donor)), fetal pre- and post-transfusion Ht values (Ht(initial), Htfinal) and percentages of HbF (HbF(initial) and HbF(final)) were used to calculate the FPV. The total red cell volume after transfusion (RCV(final)) and Ht(final) were used to estimate the plasma fluid loss.

MAIN OUTCOME MEASURES

Feto-placental blood volume and loss of plasma fluid.

RESULTS

The equations that use Htfinal over-estimate the FPV when the formula does not account for the difference between donor and post-transfusion Ht (FPV(Ht) = 21.36 * GA, - 390; r = 0.89). FPV is underestimated (FPV(Ht) = 9.90 * GA - 172; r = 0.84) when the blood volume increases with a volume less than the added donor blood volume. The calculation of FPV, using HbF percentages and the initial fetal RCV, is independent of volume changes (FPVHbF = 15.10 * GA - 279; r = 0.85). Comparing RCV(final) and Ht(final) values showed that 31.1 +/- 14.5% of the transfused volume was lost. Results of the hydropic fetuses did not differ from those of the non-hydropic fetuses.

CONCLUSIONS

FPV values based on Ht values are less reliable than those based on RCV and HbF findings. When, for practical reasons, Ht values have to be used, we propose an adapted equation for the calculation of the necessary volume of donor blood: V(donor) = FPV(HbF) * (Ht(final) - Ht(initial) / (Ht(donor) - 0.70 * Ht(final)).

Hydrops foetalis caused by anti-Mur in first pregnancy--a case report

Anti-'Mia' is the most common alloantibody of potential clinical significance in the Taiwanese population. The Mi.III phenotype is rare among Caucasians but has a high incidence in various Oriental populations. We describe a nulliparous woman with no history of transfusions, who had hydrops foetalis at 28 weeks gestation. Foetal haemoglobin was 4.4 g dL-1, and a positive direct antiglobulin test was positive in the foetal blood. Intrauterine intravascular transfusion was given, and the baby was discharged healthy. Anti-'Mia' was identified in the maternal serum, the cord blood serum and the eluate from red cells of the cord blood. Anti-'Mia' in the maternal serum was confirmed to be anti-Mur. The polymerase chain reaction-restriction fragment length polymorphism method confirmed that both the baby and her father had the Mi.III gene. Therefore, our report documents that anti-Mur has the potential to cause hydrops foetalis.

Extreme second-trimester serum analyte values in down syndrome pregnancies with hydrops fetalis

OBJECTIVE

To compare second-trimester maternal serum analyte values in Down syndrome pregnancies with, and without, hydrops fetalis.

METHODS

Seven hydropic and 85 non-hydropic Down syndrome pregnancies were identified among women with positive second-trimester maternal serum screening results. Values for maternal serum alpha-fetoprotein (MSAFP), human chorionic gonadotropin (hCG), unconjugated estriol and inhibin-A, and risks for Down syndrome were compared using the non-parametric Mann-Whitney statistical test.

RESULTS

Hydropic Down syndrome pregnancies had significantly lower MSAFP and estriol concentrations, while hCG levels were higher. For subgroups of five hydropic and 42 non-hydropic cases, no statistically significant difference in the inhibin-A levels could be demonstrated.

CONCLUSION

Second-trimester Down syndrome screening risks are significantly higher in affected pregnancies that are complicated by fetal hydrops.

Correlation of ultrasound findings and biochemical markers in the second trimester of pregnancy in fetuses with trisomy 21

OBJECTIVE

The aim of the present study was to assess possible correlations between ultrasound findings and maternal serum biochemical ('triple test') markers among fetuses with trisomy 21 in the second trimester of pregnancy.

METHODS

The study was a retrospective cohort study of 72 pregnancies affected by trisomy 21 who had a second trimester ultrasound and biochemical screen performed at a single center between 1990 and 1999. The biochemical screen consisted of alpha-fetoprotein (AFP), total beta human chorionic gonadotrophin (hCG) and estriol (uE(3)). Marker levels were expressed in multiples of the median (MoM). The ultrasound findings assessed were major structural anomalies, short humerus length, short femur length, increased nuchal fold thickness (NF), hyperechoic bowel, echogenic intracardiac focus (EIF), ventriculomegaly, choroid plexus cysts and renal pyelectasis.

RESULTS

Second trimester maternal serum biochemical markers and ultrasound findings appeared to be largely independent of each other. However, some significant correlations were observed. Estriol was significantly lower when a fetal cystic hygroma was detected on ultrasound compared to those with no cystic hygroma (0.40 vs. 0.70 MoM, p<0.05). The median hCG level was significantly lower in those pregnancies with a normal second trimester fetal ultrasound compared to those with positive ultrasound findings (2.07 vs. 2.87 MoM, p<0.05). Median hCG levels were also significantly higher in those cases with NF> or =5 mm as compared to those with NF<5 mm (2.99 vs. 2.49 MoM, p<0.05). This difference persisted after exclusion of the five cases with cystic hygromas (2.99 vs. 2.49 MoM, p<0.05). A significant positive correlation was observed between log(10) hCG and log(10) NF MoM (Spearman's rho=0.252, p<0.05). NF was significantly greater among fetuses with an identifiable cardiac defect compared with those without a detectable cardiac defect (median of 7.0 mm vs. 3.8 mm, p<0.01). This difference persisted when expressed as multiples of the median (2.8 vs. 1.3 MoM, p<0.01).

CONCLUSION

Second trimester ultrasound and biochemical markers are largely independent in fetuses with trisomy 21, however significant correlations between the two were observed in the present series. These may be important in screening protocols that combine second trimester ultrasound and biochemical markers.

Prenatal diagnosis of hemoglobin Bart's hydrops fetalis by HPLC analysis of hemoglobin in fetal blood samples

Since HbF and HbA are not found in fetuses with Hb Bart's hydrops fetalis the feasibility of prenatal diagnosis of homozygous alpha-thalassemia 1 by fetal hemoglobin typing was examined. Blood samples were obtained from fetuses at 18 to 22 weeks of gestation by cordocentesis in 32 pregnant women at risk of having a child with homozygous alpha-thalassemia 1 (alpha-thal-1). The samples were analyzed by a PCR-based method for the diagnosis of alpha-thal-1 (SEA type) and the proportion of hemoglobin fractions were determined by automated HPLC. DNA analysis showed that 8 of the 32 fetuses were homozygotes for alpha-thal-1, 17 were heterozygous for alpha-thal-1 (alpha-thal-1 trait), and a normal complement of four a-globin genes was found in 7 cases. The Hb typing in fetuses with homozygous alpha-thal-1 showed a peak of unbound Hb (Hb Bart's and Hb Portland) and no HbF, HbA and HbA The alpha-thal-1 trait chromatograms showed unbound Hb, pre HbF, HbF and HbA peaks. The chromatogram of normal fetuses showed HbF and HbA peaks without HbA2. In these cases the HbA proportion is between 3% and 10% with no apparent differences between the 18h and 22nd week of gestation. As the analysis of fetal Hb types by HPLC is facile and speedy and the results correspond with those obtained by DNA analysis, fetal Hb typing by automated HPLC is a convenient prenatal diagnostic method for homozygous alpha-thal-1. The method is recommended for prenatal diagnosis in populations with a high frequency of alpha-thal-1.

Detection of C-type natriuretic peptide in fetal circulation

C-type natriuretic peptide (CNP) belongs to the natriuretic peptide family that plays an important role in the control of blood pressure, renal function and volume homeostasis. In contrast to the atrial natriuretic peptide and brain natriuretic peptide, CNP acts in an autocrine/paracrine fashion and is considered to be the endothelial component of the natriuretic peptide system. CNP has a high expression and tissue-specific regulation in reproductive organs. Using a radio-immunoassy for CNP-22 we measured for the first time CNP in fetal blood. Samples were taken by cordocentesis in a group of fetuses with rhesus isoimmunisation (10.74 +/- 2.81 pg/ml), fetuses with rhesus isoimmunisation after intravascular transfusion (10.03 +/- 4.01 pg/ml) and a group with structural anomalies (12.9 +/- 5.67 pg/ml). A group of healthy fetuses was used as controls (11.64 +/- 4.32 pg/ml). In contrast to ANP, the fetal CNP-plasma concentrations remain stable in the investigated fetal diseases and after volume load during intravascular transfusion. Moreover, fetal CNP-plasma levels are higher than previously measured maternal concentrations in normal pregnancies. Therefore, the fetus expresses CNP independently of the maternal circulation.

The effect of fetal hydrops on the rate of fall of hemoglobin after fetal intravascular transfusion for red cell alloimmunization

OBJECTIVE

We aimed to assess whether there is a difference between hydropic and nonhydropic fetuses in the rate of fall of hemoglobin (Hb) following intravascular transfusions.

METHODS

Eighty-three intravascular transfusions in 34 fetuses were analyzed. The pretransfusion and posttransfusion Hb values, the gestational age, the volume of blood transfused, the number of days between transfusions and the rate of fall of Hb per day following a transfusion were assessed. Hb levels were expressed as multiples of standard deviation from the normal mean for gestational age.

RESULTS

Eleven fetuses were hydropic at presentation and 23 were not. Twenty-three transfusions were undertaken in the 11 fetuses while they were hydropic and 60 transfusions were performed in nonhydropic fetuses. Comparisons of transfusion variables between the two groups were performed both for the first transfusion only and also for the total number of transfusions. The rate of Hb fall per day following a transfusion was similar in the two groups on both comparisons. The posttransfusion Hb level tended to be lower and the intervals between transfusions were a little shorter in the hydropic group, but these differences were not statistically significant.

CONCLUSION

The posttransfusion Hb tended to be lower in the hydropic fetuses, but the fall in Hb was not faster in these cases. Therefore, with a similar rate of daily Hb decline in both groups, the hydropic fetuses are expected to become anemic again sooner than the nonhydropic fetuses only because of the lower posttransfusion Hb. The timing of the next transfusion should therefore be based on the posttransfusion Hb and the normal predicted drop per day irrespective of the presence or absence of hydrops.

Coagulation and fibrinolysis in viable mid-trimester pregnancies of normal, intrauterine growth retardation, chromosomal anomalies and hydrops fetalis and their eventual obstetric outcome

A total of 71 pregnant women diagnosed by ultrasound to have viable fetus in late mid- trimester pregnancies of normal, IUGR, hydrops fetalis and chromosomal anomalies were studied for their coagulation, fibrinolytic and inhibitor levels with association on eventual obstetrics outcome. A hypercoagulable state was observed in all the pregnancies studied. However, higher hypercoagulation evidenced by significantly raised prothrombin formation and clot elasticity together with higher levels of D-dimer, uPA antigen and PAI-1 than observed in normal pregnancy suggests a hyperfibrinolytic/inhibitor state in hydrops fetalis pregnancy associated with bad obstetric outcome. In IUGR pregnancy associated with good outcome further enhanced clot elasticity was seen whilst no significant differences were observed in pregnancy with chromosomal anomalies when compared to uncomplicated normal pregnancy. Our study suggests that in hydrops fetalis pregnancy, further enhanced prothrombin formation and hyperfibrinolysis/inhibitor at late mid-trimester is associated with a poor obstetric outcome.

A case for comprehensive antenatal screening for blood group antibodies

OBJECTIVES

To determine the frequency of various blood group antibodies responsible for haemolytic disease of the new born (HDN).

DESIGN

A prospective study of all neonates and still born foetuses suspected to have haemolytic disease of the new born and their mothers.

SUBJECTS

Neonates suspected to have HDN as per study criteria along with their mothers and mothers of still born foetuses with hydrops foetalis.

METHODS

Pertinent serological tests, serum bilirubin estimation, haemoglobin estimation and reticulocyte count on neonate's blood samples and demonstration/titration of blood group specific antibodies in maternal blood samples.

RESULTS

Six cases of HDN due to blood group antibodies were detected so far. Four were due to anti-D and all were of mild severity as per study criteria. Two cases were of severe haemolytic disease (hydrops foetalis). Both were due to anti Kell. Both women had history of previous blood transfusion and abortions.

CONCLUSION

Comprehensive antibody screening should be performed during antenatal period in women who have received blood transfusion and/or have history of un-explained abortions.

Prenatal diagnosis of lysosomal storage diseases using fetal blood

Lysosomal storage diseases are a rare but significant cause of non-immune hydrops fetalis (NIHF). In 17 cases of NIHF detected by ultrasound, the activity of five lysosomal enzymes was measured in leukocytes or plasma of 1 ml of fetal blood obtained by cordocentesis. By this approach seven lysosomal storage diseases known to present with hydrops fetalis can be diagnosed. In this series one case of mucopolysaccharidosis VII (M. Sly) was diagnosed at 20 weeks' gestation. The other samples allowed the establishment of reference ranges for lysosomal enzymes associated with NIHF in fetal blood. We conclude that, also in view of the poor prognosis of lysosomal storage diseases presenting with hydrops fetalis, the use of fetal blood for the early and fast biochemical diagnosis of these diseases is a valuable supplement in the diagnostic work-up and the management of NIHF.

Endothelin concentrations in monochorionic twins with severe twin-twin transfusion syndrome

The objective of this study was to determine endothelin (ET-1) concentrations in monochorionic twin fetuses with and without twin-twin transfusion syndrome (TTTS). Fourteen monochorionic twin pregnancies complicated by TTTS and six without TTTS were studied. Matched maternal and fetal blood samples were obtained both in utero and at birth. Amniotic fluid samples were also collected from twin pairs. ET-1 concentrations were measured by radio-immunoassay. ET-1 concentrations in recipient fetuses were higher than in the donors both in utero(P < 0.001) and at birth (P < 0.01). Fetal concentrations of ET-1 in donors were similar to non-TTTS twins. Plasma ET-1 concentrations were significantly higher (P < 0.01) in recipient fetuses with severe hydrops than those with mild/no hydrops. Maternal concentrations of ET-1 were comparable in the two groups. Endothelin concentrations in recipient twins were 2(1/2) times higher than in their co-twins and this was related to the severity of hydrops.

Haematological parameters of parvovirus B19 infection in 13 fetuses with hydrops foetalis

Thirteen cases of fetal parvovirus B19 infection with hydrops foetalis are reported. Viral DNA was identified by polymerase chain reaction (PCR) of amniotic fluid sampled between the 19th and the 29th week of gestation. Haematological examination revealed severe anaemia in all cases and thrombocytopenia in 11/13 cases, which was severe in two cases. Six fetuses died in utero; two after intrauterine transfusion. Complete recovery was observed in seven fetuses; five cases were treated by intrauterine transfusions, and in two cases spontaneous recovery occurred. Upon follow-up, no case of congenital anaemia was observed.

Hereditary dehydrated and overhydrated stomatocytosis: recent advances

The hereditary stomatocytoses and allied disorders are genetic defects of the erythrocyte membrane that result in abnormal permeability to the univalent cations Na+ and K+. Although rare, these conditions reflect abnormalities in physiologic mechanisms that are of paramount interest. All cases (as defined here) show increased plasma membrane permeability to Na+ and K+ and, to a greater or lesser degree, stomatocytic morphology. Dehydrated hereditary stomatocytosis, the most common form of hereditary stomatocytosis, is more heterogeneous than previously thought and includes kindreds showing pseudohyperkalemia or perinatal edema, or both. The gene responsible for both dehydrated hereditary stomatocytosis and familial pseudohyperkalemia, a nonhemolytic variant that presents with high plasma K+ levels, has been mapped to 16q23-qter. The cause of overhydrated hereditary stomatocytosis remains elusive despite the manifest lack of the enigmatic protein stomatin in the erythrocyte membrane. In all cases where splenectomy has been performed, this procedure has conferred a marked risk for thrombosis in adult life. This finding stresses the importance of diagnostic distinction between these conditions and hereditary spherocytosis.

Hematopoietic cytokine levels and in vitro colony formation assay in fetal anemia

Fetal anemia causes hydrops fetalis and fetal ascites/hydrothorax, and in severe cases the prognosis is poor. Little other than alloimmunity and viral infections are known as mechanisms causing fetal anemia. The aim of this study was to elucidate any pathogenesis in fetal anemia due to otherwise idiopathic etiology. The levels of three hematopoietic cytokines, IL-3, erythropoietin (EPO), and granulocyte colony-stimulating factor (G-CSF) were measured in blood samples obtained by cordocentesis from six fetuses with anemia (Hb <10.0 g/dl) and 34 fetuses without anemia. Cordocentesis was performed prior to the onset of labor or uterine contractions in all pregnant women. The concentration of IL-3 in fetuses with anemia [M+/-(SD), 8.3 (10.1) pg/ml] was significantly lower than that in fetuses without anemia [59.9 (71.0) pg/ml]. EPO and G-CSF levels were not different between the two groups. In addition, through in vitro colony formation assay, using blood stem cells from two fetuses with severe anemia and three fetuses without anemia, it was found that colony forming unit-erythroid, burst forming unit-erythroid and granulocyte macrophage-colony forming unit were significantly suppressed in blood stem cells from the two fetuses with severe anemia. Thus, the malfunction of differentiation and proliferation of blood stem cells and the decrease of hematopoietic cytokine levels in the fetal circulation may be responsible for the occurrence of fetal anemia.

Fluid abnormalities occur in the chronically cannulated mid-gestation but not late gestation ovine fetus

Hydrops fetalis, with or without oligo- or polyhydramnios, is associated with very high fetal mortality. In many cases the causes are unknown. Chronically cannulated ovine fetuses have been used as animal models to study the regulation of fetal fluid balance. This study reports that the mid-gestation ovine fetus (70 +/- 1 d of gestation; term = 145-150 d) is susceptible to the development of fetal abnormalities (excess allantoic fluid--hydrallantois, with or without hydrops and hydranencephaly), when blood vessels in the neck are cannulated. Cannulation of one carotid artery and one jugular vein, or cannulation of a single jugular vein resulted in 5 out of 12 fetuses having abnormalities 1 wk later. In contrast, six fetuses at 115 d of gestation that had both carotids and one jugular vein ligated cranially and cannulated, developed hydranencephaly but no hydrops or hydrallantois. In the mid-gestation fetus hydrallantois [760 +/- 140 mL (n = 5) versus 104 +/- 23 mL (n = 7 controls), p < 0.001] occurred without alterations in the plasma concentrations of ACTH, cortisol, atrial natriuretic peptide, or aldosterone, as well as without anemia. Although the causes of the fluid abnormalities were not resolved, it is important to note the developmental differences in vulnerability.

Coenzyme Q10 fetal plasma levels

OBJECTIVE

This study aims at determining a cutoff value differentiating the fetal from the adult coenzyme Q10 (CoQ10) values and comparing substantial increases in CoQ10 plasma levels in fetuses with hypoxic hypoxia and nonimmune fetal hydrops.

METHODS

We have selected 61 pregnancies and determined the CoQ10 levels in fetal and maternal samples obtained by cordocentesis. Our study included a control group and pregnancies with intrauterine growth retardation, Rh isoimmunization, nonimmune fetal hydrops, and fetal malformations.

RESULTS

To differentiate the fetal from the adult values we have set 0.3 mg/ml as the cutoff value. The CoQ10 were higher only in fetuses with hypoxic hypoxia and nonimmune hydrops.

CONCLUSION

Normal fetal CoQ10 plasma levels are lower than 0.3 mg/ml.

Human parvovirus B19: immunity of Greek females and prenatal investigation of hydrops fetalis

Sera from 308 healthy Greek females of reproductive age were examined for specific IgG antibodies to human parvovirus B19 by recombinant-Elisa to determine the immunity rates of this part of population to parvovirus B19. Also paired maternal sera and amniotic fluids from nine pregnancies with hydrops fetalis were investigated for specific IgG and IgM antibodies and parvovirus DNA by polymerase chain reaction and southern hybridization analysis. The latter study was conducted to find out the participation of parvovirus B19 infection in hydrops fetalis cases in Greece. The overall prevalence of IgG antibodies in healthy Greek females was at a rate of 57.8% rising with age. One case of hydrops fetalis out of the nine examined, was diagnosed prenatally as parvovirus B19 maternal-fetal infection. It was a twin pregnancy with one fetus hydropic and the other growth retarded. Premature birth of liveborn infants was followed by neonatal death, 48 h after delivery. The contribution of parvovirus B19 in cases of non-immune hydrops fetalis was at 11% in this part of the world.

A severe transfusion-dependent congenital dyserythropoietic anaemia presenting as hydrops fetalis

We describe a case of congenital dyserythropoietic anaemia (CDA) presenting at week 20 of pregnancy with hydrops fetalis and very severe anaemia. Fetal blood examination showed marked erythroblastosis with morphologic alterations while the basic haematological and biochemical tests were in the normal range. The fetus received intravascular red blood cells transfusion at 20 and 25 weeks of gestation. After a caesarean section at week 33 the child became transfusion dependent. Haematological investigations demonstrated that the child is affected by a CDA-like picture which, although morphologically similar to CDA II, is Ham test negative and does not show the typical membrane proteins alterations.

Molecular defects in Hb H hydrops fetalis

The molecular defect in two unique cases of Hb H hydrops fetalis has been characterized. Both cases are due to co-inheritance of a 'non-deletion' defect affecting the alpha2 gene: at codon 30 delta GAG, Glu) and codon 59 (G --> A, Gly --> Asp) respectively, and a zeta-alpha thalassaemia (thal) 1 or alpha thal 1 genotype. These two non-deletion defects, unlike previously described cases, resulted in severe anaemia of the fetuses and emphasize the importance of performing prenatal diagnosis for these families.

Hyperphosphatasemia in early diagnosed infantile GM1 gangliosidosis presenting as transient hydrops fetalis

The authors report a case of unsuspected fetal storage disorder initially diagnosed by placental examination performed because of a transient ascites at 28 weeks of gestation. At birth mild dysmorphic features and gradual neurological deterioration were observed. Highly elevated alkaline phosphatase levels were repeatedly noticed. Deficiency of beta-galactosidase was documented confirming GM1 gangliosidosis. Previous reports described the placental pathology after positive prenatal diagnoses of lysosomal diseases. In the present case, the postnatal diagnosis was made in view of the placental pathologic findings. Our observation indicates the need for thorough investigations in hydrops fetalis, in search for metabolic diseases.

Hematologic disorders and nonimmune hydrops fetalis

Hematologic disorders are implicated in approximately 10% to 27% of cases of nonimmune hydrops fetalis. In almost all of these disorders, anemia leading to heart failure, edema, ascites, and anasarca is the final common denominator. The etiology of the anemia in these cases can be conveniently divided into two categories: (1) excessive erythrocyte loss by hemolysis or hemorrhage, and (2) erythrocyte underproduction. The former include intrinsic erythrocyte abnormalities such as alpha-thalassemia and glucose-6-phosphate dehydrogenase deficiency, and conditions with excessive fetal blood loss such as fetomaternal hemorrhage and twin-twin transfusion. The latter include bone marrow replacement syndromes and conditions associated with failure of erythrocyte production. The presentation, diagnosis, and management of hematologic disorders associated with nonimmune hydrops fetalis are reviewed.

Lethal alpha-thalassaemia created by gene targeting in mice and its genetic rescue

Mutations at the alpha-globin locus are the most common class of mutations in humans, with deletion of all four adult alpha-globin genes resulting in the perinatal lethal condition haemoglobin Barts hydrops fetalis. Using gene targeting in mice, we have deleted a 16 kilobase region encompassing both adult alpha-globin genes. Animals homozygous for this deletion become hydropic and die late in gestation mimicking humans with hydrops fetalis. Introduction of a human alpha-globin transgene rescued these animals from perinatal death thus demonstrating the utility of this murine model in the development of cellular and gene based approaches for treating this human genetic disease.

Hydrops fetalis caused by a blood group antibody usually undetected in routine screening

A case of isoimmunisation in pregnancy caused by antibodies to the Kpa red blood cell antigen is described. The preceding pregnancy had resulted in fetal hydrops for which no cause was found as the antibody screening cells used to investigate the fetal hydrops were Kpa negative. This case emphasises the importance of serological screening at a reference laboratory for low frequency red cell antigens before a diagnosis of non-immune hydrops is made.