Neonatal outcomes of pregnancies affected by haemolytic disease of the foetus and newborn and managed with intrauterine transfusion: a service evaluation

Background

This study, conducted in the tertiary Foetal Medicine Unit at St Michael’s Hospital, Bristol, was designed to obtain information regarding neonatal outcomes of pregnancies affected by haemolytic disease of the foetus and newborn and managed by intrauterine transfusion, and to determine whether a change in intrauterine transfusion protocol in 2004 had improved safety. The new protocol included attendance of two Foetal Medicine Unit consultants, foetal sedation and use of the intrahepatic vein as an alternative route to placental cord insertion if deemed safer.

Materials and methods

Data for pregnancies affected by haemolytic disease of the foetus and newborn as a result of haemolytic red cell alloimmunisation and managed with intrauterine transfusion at St Michael’s Hospital between 1999 and 2009 were retrospectively collected using local databases, and medical note review.

Results

Overall, 256 relevant intrauterine transfusions were performed. The median number of intrauterine transfusions per pregnancy was two. Ninety-three per cent of the live deliveries had 5-minute APGAR scores ≥9 and 98% were admitted to a Neonatal Intensive Care Unit/Special Care Baby Unit, requiring phototherapy (96%), top-up transfusions (44%: 23.2% immediate, 13.4% late, 7.3% both), and exchange transfusion (37%). An association was found between increased intrauterine transfusion number and reduced phototherapy duration and hospital admission: each additional intrauterine transfusion reduced the duration of phototherapy by 16% (95% CI: 0.72–0.98), and Neonatal Intensive Care Unit/Special Care Baby Unit admission by 44% (95% CI: 0.48–0.66). Following the change in intrauterine transfusion protocol, there was a significant reduction in the number of emergency Caesarean sections occurring directly after an intrauterine transfusion (n =5 vs 0; P =0.02). The foetal loss rate within 48 hours of an intrauterine transfusion was 1.9% per pregnancy, or 0.8% per intrauterine transfusion: no losses occurred under the new protocol (n =3 vs 0; P = NS).

Discussion

Although the majority of neonates required admission to a Neonatal Intensive Care Unit/Special Care Baby Unit and phototherapy, the medium-term outcomes were positive. Importantly, the safety of the intrauterine transfusion procedure has improved significantly since the change in protocol.     

Thrombocytopenia at birth in neonates with red cell alloimmune haemolytic disease

Objective To evaluate the incidence and severity of and risk factors for thrombocytopenia at birth in neonates with red cell alloimmunization. Study design All neonates with haemolytic disease of the foetus/newborn (HDFN) due to red cell alloimmunization admitted to our centre between January 2000 and September 2010 were included in this retrospective study. We measured platelet counts at birth and determined the incidence of thrombocytopenia (platelet count < 150 × 10⁹/l) and severe thrombocytopenia (platelet count < 50 × 10⁹/l). Risk factors for thrombocytopenia at birth were evaluated. Results Thrombocytopenia was present in 26% (94/362) of included neonates with HDFN at birth. Severe thrombocytopenia was found in 6% (20/362) of neonates. Three risk factors were found to be independently associated with thrombocytopenia at birth: treatment with intrauterine red cell transfusion (IUT) (OR 3·32, 95% CI 1·67–6·60, P = 0·001), small for gestational age (SGA) below the 10th percentile (OR 3·32, 95% CI 1·25–8·80, P = 0·016) and lower gestational age at birth (OR 1·22/week, 95% CI 1·02–1·44, P = 0·025). Conclusions Thrombocytopenia at birth occurs in 26% of neonates with HDFN due to red cell alloimmunization and is independently associated with IUT treatment, SGA and lower gestational age at birth.     

Survey on the prevention and incidence of haemolytic disease of the newborn in Italy

Background

In 2010, the Italian Society of Immunohaematology and Transfusion Medicine (SIMTI) carried out a survey of the incidence of haemolytic disease of the newborn (HDN) and the prevention of HDN caused by anti-Rh(D) in Italian Transfusion Structures (TS).

Materials and methods

A questionnaire divided into the following five sections was administered: (i) types of services provided and maintenance of legally required registers, (ii) immunoprophylaxis (IP), (iii) red cell typing and searches for irregular antibodies, (iv) evaluation of foetal-maternal haemorrhage (FMH), and (v) incidence of HDN in 2010. Of the 280 TS sent the questionnaire, 176 (63%) replied.

Results

A HDN register was available in 55.5% of the TS (n =91). Immunoprophylaxis with a dose of anti-D IgG was given to all Rh(D) negative and Rh(D) variant puerpera with Rh(D) positive newborns: in more than 93% of cases the dose was between 1,500 IU (300 μg) and 1,250 IU (250 μg). Antenatal IP between the 25^th and 28^th week was proposed by 42 TS (26%). Seventy percent of the TS (n =115) did not make any evaluation of FMH. The number of births surveyed in 2010 was 203,384, the number of Rh(D) negative pregnancies was 13,569, while anti-D antibodies were present in 245 pregnancies. There were 111 cases of HDN due to anti Rh(D) incompatibility and in 40 of these, intrauterine transfusion (n =8) or exchange transfusion (n =32) was necessary. In 94 cases HDN was due to other irregular antibodies: in 4 of these cases intrauterine transfusion was needed and in 11 other recourse was made of exchange transfusion. Finally, there were 1,456 newborns with ABO HDN of whom 13 underwent exchange transfusion.

Discussion

The data collected give a picture of the incidence of HDN in Italy and of the methods of managing IP and could form the basis for an update of the SIMTI recommendations on the management and prevention of this disease.     

Predicting the severity of haemolytic disease of the newborn: an assessment of the clinical usefulness of the chemiluminescence test

Summary. The ability of the chemiluminescence test (CLT) to predict the severity of haemolytic disease of the newborn (HDN) was determined in 80 alloimmunized pregnant women who delivered antigen-positive babies. In 54 cases of alloimmunization to D, results from the CLT showed better correlation with fetal outcome than anti-D concentration measured by AutoAnalyzer (r = 0.70 and 0.36 respectively). Results from the CLT permitted a threshold level of antibody activity (30%) below which 15/20 babies were unaffected or had mild disease, and only one required transfusion therapy in utero. CUT results above 30% were associated with moderate or severe disease in all cases.
Results from the AutoAnalyzer proved a less reliable predictor of disease severity; three women with anti-D levels >20iu/ml delivered unaffected babies, and two women with anti-D levels <10iu/ml delivered babies who had required transfusion in utero. The clinical usefulness of the CLT derives from the possibility of avoiding invasive monitoring procedures in women with high levels of anti-D which is relatively non-functional.     

A survey of the current use of anti-D immunoprophylaxis and the incidence of haemolytic disease of the newborn in Italy

Introduction

The Italian Society of Transfusion Medicine and Immunohaematology (SIMTI) carried out a survey on the current use of anti-D immunoprophylaxis (IP) in Italy, on its ways of use and on the impact that it has had on decreasing haemolytic disease of the newborn (HDN), due to maternal-foetal incompatibility for the D antigen.

Materials and methods

The survey was carried out using a questionnaire prepared by the Working Group established for this purpose by the SIMTI. The questions were divided into five groups: the ways of carrying out IP, evaluation of foetal-maternal haemorrhage, serological tests after IP, the current incidence of HDN, and data on exchange transfusions.

Results

Data were obtained from 69 Transfusion Services (TS). Four of these give IP antenatally, whereas in the remaining cases IP is given after birth. Almost all the TS evaluate the amount of foetal-maternal haemorrhage in order to give additional doses of anti-D IgG, with the most widely used method being the Kleihauer-Betke test. Data were collected from 176,010 pregnancies: 18,639 were D-negative women, of whom 18,440 were not immunised. There were 136 cases of HDN with anti-D antibodies, and 39 of these required exchange transfusions (ET). Furthermore, there were 1,535 pregnant women with anti-A and/or anti-B IgG, which were clinically significant in 83 and required ET in 37. Finally, 40 women had antibodies, directly related to the pregnancy, against antigens other than D (in eight of these cases ET was necessary).

Conclusions

The survey carried out by SIMTI was able to give a sufficiently full and accurate picture of current Italian practices concerning the use and ways of use of anti-D IP in pregnancy and the puerperum, as well as the incidence and characteristics of HDN. Furthermore, this survey was the basis for guidelines on the management of HDN, produced by SIMTI in collaboration with the Italian Society of Obstetricians and Gynaecologists.     

A prospective study of routine antenatal enzyme antibody screening demonstrates lack of clinical value in predicting haemolytic disease of the newborn

A prospective study of 7065 consecutive new pregnancies identified 230 with a positive screen, of which 27% (62/230) were 'enzyme-only' antibodies. 32 of these (52%) were potentially clinically important and were all of Rh specificity: 22 anti-E, seven anti-Cw, two anti-D and one anti-c. However, only three of these enzyme-only antibodies (one anti-D, one anti-c and one anti-E) became reactive by the indirect antiglobulin test (IAT) during the course of pregnancy, and all were detected in the routine 34-36-week maternal sample. No babies were affected, and we reaffirm that routine antibody screening by enzyme techniques is unnecessary.     

High incidence of maternal HLA A, B and C antibodies associated with a mild course of haemolytic disease of the newborn. Group for the Study of Protective Maternal HLA Antibodies in the Clinical Course of HDN.

Mild courses of haemolytic disease of the foetus or newborn (HDN) due to Rh (D) blood group antibodies are associated with and may therefore be ameliorated by maternal antibodies reacting with human leucocyte antigens (HLA) of the child, an observation drawn from our own earlier data (Neppert J, Kissel K. Lancet 1992;339:1481). This study (i) corroborates this association; (ii) reveals shortcomings in the published data; and (iii) examines the characteristics of HDN cases when these shortcomings have been rectified. Samples from 51 women with antibodies against their child's blood group antigens of the Rh system were analysed for HLA A, B, C and DR antibodies during parturition. The mothers were divided into two groups, either severe or mild, dependent upon the clinical course of the HDN, and the incidence of HLA antibody production was determined for each group. HLA A, B, C and/or DR antibodies were detected in 85.2% of those women whose children had a mild course of HDN prenatally or perinatally (n=27). This is statistically greater than the incidence of 50.0% (Fisher's exact test: p=0.014) found in the group of women whose children had a severe HDN either pre- or perinatally (n=24) and is greater than the 35% (n=20; p=0.0001) found in women without Rh or other irregular antibodies. HLA DR antibodies were detected in three cases. The findings support our hypothesis that maternal anti HLA A, B and C antibodies may protect against a potential severe HDN. We therefore assume that those women will benefit who have already had a child with a severe HDN and in whom HLA antibodies were not previously detected, if HLA antibody production is provoked by subcutaneously inoculating with the father's leucocytes before or at the beginning of the new pregnancy.     

Necrotizing enterocolitis： A multifactorial disease with no cure

Necrotizing enterocolitis is an inflammatory bowel disease of neonates with significant morbidity and mortality in preterm infants. Due to the multifactorial nature o the disease and limitations in disease models, early diagnosis remains challenging and the pathogenesis elusive. Although preterm birth, hypoxic-ischemic events formula feeding, and abnormal bacteria colonization are established risk factors, the role of genetics and vasoactive/inflammatory mediators is unclear Consequently, treatments do not target the specific underlying disease processes and are symptomatic and surgically invasive. Breast-feeding is the most effective preventative measure. Recent advances in the prevention of necrotizing enterocolitis have focused on bioactive nutrients and trophic factors in human milk. Developmen of new disease models including the aspect of prematurity that consistently predisposes neonates to the disease with multiple risk factors will improve our understanding of the pathogenesis and lead to discovery of innovative therapeutics.     

Blocked D phenomenon, a rare condition with Rh D haemolytic disease of newborn - a case report

Accurate Rh testing can be difficult if the red cells are heavily coated with IgG anti D antibodies - a phenomenon called blocked D. Repeatedly, Rh D negative blood group report was obtained in a newborn male baby with severe haemolytic disease and features of kernicterus born to a 2nd gravida B Rh D negative mother. On investigation, the baby was grouped as B Rh D negative by direct grouping, but after elution, D antigen was detected and phenotyped as CcDe. Antibody was identified as anti D. All D antigens of the baby were fully saturated with anti D leaving any antigen to bind with antisera. Direct Coombs test was strongly positive even after three exchange transfusions. The baby also had free antibody apart from the red cell bound and the red cell eluate, gave a titre of 512. The mother was grouped as B Rh D negative and phenotyped as ce. She had IgM and IgG class of anti D with titres 32 and 1024 respectively. She also had IgM anti C (only in neat) and IgG anti-A with a titre of 512.     

Relationship between previous maternal transfusions and haemolytic disease of the foetus and newborn mediated by non-RhD antibodies

Background

The aim of this study was to determine the relationship between non-RhD immunisation and the consequent development of haemolytic disease of the newborn in pregnant women with a history of red blood cell transfusion compared to those without a history of transfusion.

Materials and methods

This retrospective cohort study included all pregnancies with red blood cellantibodies that were tested between 1993 and 2010. Data were obtained from the forms for immunisation tracking at the Department of Transfusion Medicine. Each form contained data on previous maternal transfusions, antibody specificities and whether the antibodies caused haemolytic disease of the newborn.

Results

Clinically significant non-RhD antibodies was found in 214 of 108,000 pregnancies, of which the most frequent were anti-E (n =55), anti-K (n =54), and anti-c (n =52) antibodies. A history of red blood cell transfusion was identified in 102 (48%) of the pregnancies in which non-RhD antibodies were found (in 78% of the anti-K cases, 40% of the anti-c and 18% of the anti-E cases). Non-RhD antibodies caused haemolytic disease of the newborn in 44 cases of which 14 were very severe (2 anti-K, 8 anti-c, 3 anti-Rh17, 1 anti-E). The mother had a positive history of red blood cell transfusion in 39% of the cases of haemolytic disease of the newborn. Anti-c antibodies were involved in all cases with severe haemolytic disease of the newborn and a history of maternal red blood cell transfusion.

Conclusion

Primary prevention by using K-negative, Rhc-, RhE-, and RhC-compatible red blood cell transfusion for women younger than 45 years may prevent up to 40% of cases of haemolytic disease of the newborn. Rhc compatibile transfusion is the most important prevention strategy against severe haemolytic disease of the newborn caused by non-RhD antibodies.     

Low anti‐RhD IgG‐Fc‐fucosylation in pregnancy: a new variable predicting severity in haemolytic disease of the fetus and newborn

Haemolytic disease of the fetus and newborn (HDFN) may occur when maternal IgG antibodies against red blood cells (RBCs), often anti‐RhD (anti‐D) antibodies, cross the placenta and mediate the destruction of RBCs via phagocytic IgG‐Fc‐receptors (FcγR). Clinical severity is not strictly related to titre and is more accurately predicted by the diagnostically‐applied monocyte‐based antibody‐dependent cellular cytotoxicity (ADCC), a sensitive test with relatively low specificity. This suggests that other factors are involved in the pathogenesis of HDFN. Binding of IgG to FcγR requires the N‐linked glycan at position 297 in the IgG‐Fc‐region, consisting of several different glycoforms. We therefore systematically analysed IgG‐derived glycopeptides by mass spectrometry from 70 anti‐D IgG1 antibodies purified from the plasma of alloimmunized pregnant women. This revealed a variable decrease in Fc‐fucosylation in the majority of anti‐D IgG1 (even down to 12%), whereas the total IgG of these patients remained highly fucosylated, like in healthy individuals (>90%). The degree of anti‐D fucosylation correlated significantly with CD16 (FcγRIIIa)‐mediated ADCC, in agreement with increased affinity of defucosylated IgG to human FcγRIIIa. Additionally, low anti‐D fucosylation correlated significantly with low fetal‐neonatal haemoglobin levels, thus with increased haemolysis, suggesting IgG‐fucosylation to be an important pathological feature in HDFN with diagnostic potential.     

Haemolytic disease of the fetus and newborn

Haemolytic Disease of the Fetus and Newborn (HDFN) is caused by maternal alloimmunization against red blood cell antigens. In severe cases, HDFN may lead to fetal anaemia with a risk for fetal death and to severe forms of neonatal hyperbilirubinaemia with a risk for kernicterus. Most severe cases are caused by anti‐D, despite the introduction of antental and postnatal anti‐D immunoglobulin prophylaxis. In general, red blood cell antibody screening programmes are aimed to detect maternal alloimmunization early in pregnancy to facilitate the identification of high‐risk cases to timely start antenatal and postnatal treatment. In this review, an overview of the clinical relevance of red cell alloantibodies in relation to occurrence of HDFN and recent views on prevention, screening and treatment options of HDFN are provided.     

Cyril Clarke and the prevention of rhesus haemolytic disease of the newborn

Cyril Clarke was an outstanding general physician and lepidopterist. Late in his career, and stimulated by his work on the genetics of mimicry in butterflies, he became interested in the evolving field of medical genetics. His work on the relationship of blood groups to particular diseases led him and his team in Liverpool to evolve a remarkably successful approach to the prevention of Rhesus haemolytic disease of the newborn.     

First case of haemolytic disease of the newborn due to anti-Mur in Hong Kong

The fifth child of a Hong Kong Chinese mother developed moderate jaundice, attributable to antibodies (anti-Mi) against antigenic determinants in GP. Mur (Miltenberger, class III) red cells. Both the father and the eldest sister were of the phenotype GP. Mur. Testing of maternal serum against a red cell panel including cells known to carry the antigenic determinants of some Miltenberger phenotypes revealed the presence of anti-Mur. This report documents the first case of haemolytic disease of the newborn (HDN) due to anti-Mur in Hong Kong.     

Factors associated with persistence of red blood cell antibodies in woman after pregnancies complicated by fetal alloimmune haemolytic disease treated with intrauterine transfusions

Red blood cell (RBC) antibodies can persist for decades or decrease quickly to undetectable levels. Antibody persistence has not been systematically studied. Women whose children are treated with intrauterine transfusions (IUT) for haemolytic disease of the fetus (HDFN) often produce additional antibodies, which can be evoked by the intrauterine transfusion or by fetomaternal haemorrhage during the procedure. Factors associated with persistence of both the antibodies responsible for HDFN and additional antibodies were studied in 260 women whose children were treated with IUT between 1988 and 2008. They possessed 499 (205 anti‐D and 294 non‐D) antibodies after the last IUT. After a median follow‐up of 8·7 years, all 260 antibodies primarily responsible for HDFN had persisted. Additional antibodies directed against antigens of the children persisted in 70·6%, and in 32·3% if they were not child‐specific (P < 0·001). Antibodies induced by irradiated IUT persisted in only 7·1%. Multivariate analyses showed that non‐HDFN antibody persistence was dependent on the antibody titre and specificity. In conclusion, persistence of antibodies mainly depends on antibody strength and specificity. Difference between fetal or non‐fetal immunogens suggests maintenance of antigenic stimulation possibly by long‐term fetomaternal chimerism.     

Infantile pyknocytosis: a cause of haemolytic anaemia of the newborn

This study defined the incidence, clinical and haematological characteristics of infantile pyknocytosis in a monocentric retrospective study of 149 blood samples referred for unexplained neonatal haemolytic anaemia. Pyknocytosis was diagnosed in 14 patients (9.4%). All patients had neonatal jaundice and severe anaemia (mean nadir haemoglobin: 6.8 g/dl) at a mean age of 21 d. The percentage of pyknocytes was 4-23%. Packed red blood cell transfusions were needed in 11 of 14 patients. Haemoglobin levels reached normal values within a mean time of 4 months. Infantile pyknocytosis is an unusual cause of neonatal haemolytic anaemia, which requires careful examination of blood smears.     

Algorithm development and diagnostic accuracy testing for non-invasive foetal RHD genotyping: an Indian experience

BackgroundThe discovery of the cell-free foetal DNA (cffDNA) circulating in the maternal plasma enabled prediction of foetal RHD thus eliminating the risks associated with invasive procedures. Non-invasive foetal RHD genotyping has now become the standard approach in developed countries for management of alloimmunised women and is also used for targeted antenatal prophylaxis in non-alloimmunised women.Materials and methodscffDNA was extracted from the plasma of 217 RhD negative pregnant women at a gestational age of 10–34 weeks. The foetal RHD genotype was determined by real-time polymerase chain reaction (real-time PCR) amplification of exons 4, 5 and 10 in duplicates. After an initial 54 samples, foetal typing was carried out with RHD exons 5 and 10 for the remaining samples. CCR5, SRY and RASSF1A genes were used as controls. Results were compared with cord blood serological typing at birth.ResultsOut of the 217 women, 193 were non-immunised and 24 were alloimmunised. A conclusive diagnosis was obtained in 203 samples. Diagnosis was inconclusive in 14 samples; of these, foetal RHD genotype could be resolved in six samples after maternal and paternal RHD genotyping. A 100% diagnostic accuracy, sensitivity and specificity were demonstrated in 209 women who had had a conclusive result. When the inconclusive samples were included, diagnostic accuracy and sensitivity were more than 95% and specificity was 78.95%.DiscussionAnti-D is still the leading cause of haemolytic disease of the foetus and the newborn in India. There is, therefore, a need to establish and develop an algorithm for antenatal RhD negative women in India. The positive results of non-invasive foetal RHD genotyping, from the start of the 10^th week of gestation using two RHD exons giving 100% diagnostic accuracy, show promise for routine diagnostic use to the benefit of the antenatal RhD negative Indian population.