Severity of haemolytic disease of the fetus and newborn in patients with a history of intrauterine transfusions in a previous pregnancy: A nationwide retrospective cohort study

OBJECTIVE

Pregnant women who received at least one intrauterine transfusion (IUT) for haemolytic disease of the fetus and newborn (HDFN) in the preceding pregnancy are presumed to have a high likelihood of requiring IUTs again, often starting at an earlier gestational age. Our aim was to quantify these risks in a large national cohort.

DESIGN

Retrospective cohort study of a nationwide Dutch database.

SETTING

The Netherlands.

POPULATION

All women treated in The Netherlands with IUTs for Rhesus D (RhD)- or Kell-mediated HDFN between 1999 and 2017 and their follow-up pregnancies were included. Pregnancies with an antigen-negative fetus were excluded.

METHODS

Electronic patient files were searched for the number and gestational age of each IUT, and analysed using descriptive statistics and linear regression.

MAIN OUTCOME MEASURES

Percentage of women requiring one or more IUTs again in the subsequent pregnancy, and gestational age at first IUT in both pregnancies.

RESULTS

Of the 321 women in our study population, 21% (69) had a subsequent ongoing pregnancy at risk. IUTs were administered in 86% (59/69) of cases. In subsequent pregnancies, the median gestational age at first IUT was 3 weeks earlier (interquartile range -6.8 to 0.4) than in the preceding pregnancy.

CONCLUSIONS

Our study shows that pregnant women with a history of IUTs in the previous pregnancy are highly likely to require IUTs again, and on average 3 weeks earlier. Clinicians need to be aware of these risks and ensure timely referral, and close surveillance from early pregnancy onwards. Additionally, for women with a history of IUT and their caregivers, this information is essential to enable adequate preconception counselling.

A study on diagnostic performance of different immunohematological diagnostic tests in assessing the prevalence of ABO Hemolytic Disease of Newborn in the antenatal O group mothers and their neonatal outcome in a tertiary care hospital in Northern India

BACKGROUND

Hemolytic disease of the newborn (HDN) results in the decreased lifespan of the red cells. HDN related to ABO incompatibility is mostly unnoticed because routine screening is not being done. This study was done to assess the prevalence of ABO-HDN and to compare different immunohematological tests. Methods-In this study 213 O group mothers and the 122 ABO-incompatible newborns born to them were included. Quantifying the maternal IgG anti-A/anti-B antibody titer was done by Conventional Tube Technique (CTT) using Dithiothreitol (DTT) pretreated maternal serum. Hemolysin test was performed on the mothers having titer > 256. These cases were followed up and, after delivery, were monitored for ABO HDN, along with direct antiglobulin testing and elution studies. The prevalence of ABO-HDN was calculated, and the different diagnostic parameters of the tests were calculated. Results- The prevalence of ABO-HDN in our population was estimated to be 1.7%, 6.1% & 10.6% in our population, O group mothers, and O group mothers with ABOincompatible newborns, respectively. Maternal titer≥ 512 strongly correlated with ABOHDN. DAT positivity is a good predictor of ABO-HDN, especially using sensitive techniques. Maternal IgG titers have the highest sensitivity & Negative Predictive Value, while DAT has the highest specificity & Positive Predictive Value. Conclusion - Maternal ABO antibody titration may be advocated in the centers to identify high-risk groups. It can advocate institutional delivery and dedicated follow-up of newborns with ABO-HDN. Blood grouping & DAT may be performed in all newborns born to O blood group to identify high-risk cases.

Neonatal hemolytic disease: How should we use indirect and direct antiglobulin tests?

BACKGROUND

In newborns with hemolysis, the direct antiglobulin test (DAT) and indirect antiglobulin test (IAT) play a key role in demonstrating the presence of an immune cause. We aimed to emphasize the importance of IAT in mothers of DAT-positive babies.

METHODS

DAT was performed with forward blood grouping on cord blood in term babies who were born between September 2020 and September 2022. IAT was performed in the mothers of the babies who were found to have a positive DAT and antibody identification was performed in the mothers who were found to have a positive IAT. Specific antibodies detected and identified were associated with the clinical course.

RESULTS

The study included 2769 babies and their mothers. The prevalence of DAT positivity was found to be 3.3% (87 of 2661). In DAT-positive babies, the rate of ABO incompatibility was 45.9%, the rate of RhD incompatibility was 5.7% and the rate of RhD and ABO incompatibility in association was 10.3%. The rate of subgroup incompatibility and other red blood cell antibodies was 18.3%. Phototherapy was applied because of indirect hyperbilirubinemia in 16.6% of the DAT-negative babies and in 51.5% of the DAT-positive babies. The need for phototherapy was significantly higher in DAT-positive infants (p < 0.01). Severe hemolytic disease of the newborn, bilirubin level, duration of phototherapy and use of intravenous immunoglobulin were found to be significantly higher in the babies whose mothers were IAT positive compared with the babies whose mothers were IAT negative (p < 0.01).

CONCLUSIONS

IAT should be performed on all pregnant women. When screening with IAT is not performed during pregnancy, performing DAT in the baby plays a key role. We showed that the clinical course was more severe when mothers of DAT-positive babies were IAT positive.

Anti-C causing severe hemolytic disease of the fetus and newborn: a rare case report

Hemolytic disease of the fetus and newborn (HDFN) due to anti-D was severe and fatal before the development of RhD immune prophylaxis. Proper screening and universal administration of Rh immune globulin has decreased the incidence of HDFN to a great extent. Pregnancy, transfusion, and transplantation still increase the chances of other alloantibody formation and the potential for HDFN. Advanced methods for immunohematology investigation allow for the identification of alloantibodies causative for HDFN other than anti-D. Many antibodies have been reported to cause HDFN, but there is scant literature where isolated anti-C is responsible for HDFN. We present here a case of severe HDFN caused by anti-C leading to severe hydrops and death of the neonate despite three intrauterine transfusions and other measures.

Immunoglobulin for hemolytic jaundice in Japan: A retrospective survey

BACKGROUND

Intravenous immunoglobulin G (IVIG) is used to treat blood-type incompatibility hemolytic disease of newborns (BTHDN). Although IVIG's efficacy for treating BTHDN has been challenged, as an updated systematic review suggests, IVIG could significantly reduce exchange transfusions. We conducted a mail-in questionnaire survey to ascertain actual use of IVIG for BTHDN in Japan.

METHODS

The survey, conducted in 2014, included infants born between January 1, 2009, and December 31, 2013. Questionnaires were sent to the heads of neonatal intensive care units (NICUs) at perinatal centers of the Japan Neonatologist Association.

RESULTS

A total of 195 centers (64.6%) responded to the questionnaire. During the study period, 170 centers (87.2%) reported incidences of BTHDN. Among these centers, there were 1726 diagnosed cases of BTHDN in neonates. Of these cases, 419 infants were treated with IVIG in 127 centers, representing approximately 74.7% of all centers. After the exclusion of cases with missing data and those where consent for data usage was not obtained, a total 916 infants were included in this study. Of these, 219 (23.9%) were treated with IVIG after phototherapy, and 187 (20.4%) of these infants did not require further blood exchange transfusion. The IVIG dosages ranged from 40 to 1200 mg/kg/dose, but the majority were between 500 and 1000 mg/kg/dose, with a median of 800 mg/kg/dose. About 20% of the infants treated with IVIG showed late-onset anemia and required treatment. Adverse events were reported in less than 1% of infants.

CONCLUSIONS

For the treatment of BTHDN, IVIG administration was widely used in NICUs in Japan without severe adverse events.

Distribution of maternal red cell antibodies and the risk of severe alloimmune haemolytic disease of the foetus in a Chinese population: a cohort study on prenatal management

BACKGROUND

Haemolytic disease of the foetus and newborn (HDFN) is the most common aetiology of haemolytic anaemia and hyperbilirubinaemia in foetuses and neonates. Studies on the distribution of antibodies that cause haemolytic disease of the foetus (HDF) in China are limited, and the effects of multiple antibodies on the severity of HDF need further evaluation.

METHODS

An observational cohort study from January 2005 to December 2019 was conducted in two hospitals affiliated with Sun Yat-sen University. Maternal red cell alloimmunization was identified by the Guangzhou Blood Centre. In total, 268 pregnant woman-foetus pairs were divided into four groups according to the type of maternal alloantibodies: anti-D, anti-D combined with other antibodies, other single-antibody and other multiple antibodies. The obstetric history, antibody characteristics, incidence of severe HDF and foetal outcomes were collected and compared. Logistic regression analysis of the risk factors for HDF and survival analysis of the severe HDF-free interval were conducted.

RESULTS

Anti-D was the most common cause of HDF, followed by anti-M. No anti-K- or isolated anti-c-associated HDF was found. The incidence of severe HDF was higher in the group with anti-D combined with other antibodies than in the group with anti-D alone (P = 0.025), but no significant difference was found in haemoglobin level and reticulocyte count in the anaemic foetuses between these two groups. Foetuses in the other single-antibody group had a lower reticulocyte count (P = 0.007), more IUTs (P = 0.007) and an earlier onset of severe HDF (P = 0.012). The maximum antibody titre was significantly lower in the other single-antibody group than in the anti-D group (P < 0.001). A high maternal antibody titre (P < 0.001), multiple affected pregnancies (P < 0.001) and other single-antibody (P = 0.042) were independent risk factors for HDF. A higher reticulocyte count (P = 0.041) was an independent risk factor for severe HDF in anaemia foetuses affected by Rh(D) alloimmunization.

CONCLUSIONS

The distribution of HDF-associated antibodies in China is different from that in Western countries. Other single non-Rh(D) antibodies could increase the risk of HDF, and anti-D combined with other antibodies would not influence the severity of foetal anaemia compared with anti-D alone.

Hemolytic disease of the fetus and newborn due to Rh(D) incompatibility: A preventable disease that still produces significant morbidity and mortality in children

In the mid-20th century, Hemolytic Disease of the Fetus and Newborn, caused by maternal alloimmunization to the Rh(D) blood group antigen expressed by fetal red blood cells (i.e., "Rh disease"), was a major cause of fetal and neonatal morbidity and mortality. However, with the regulatory approval, in 1968, of IgG anti-Rh(D) immunoprophylaxis to prevent maternal sensitization, the prospect of eradicating Rh disease was at hand. Indeed, the combination of antenatal and post-partum immunoprophylaxis is ~99% effective at preventing maternal sensitization to Rh(D). To investigate global compliance with this therapeutic intervention, we used an epidemiological approach to estimate the current annual number of pregnancies worldwide involving an Rh(D)-negative mother and an Rh(D)-positive fetus. The annual number of doses of anti-Rh(D) IgG required for successful immunoprophylaxis for these cases was then calculated and compared with an estimate of the annual number of doses of anti-Rh(D) produced and provided worldwide. Our results suggest that ~50% of the women around the world who require this type of immunoprophylaxis do not receive it, presumably due to a lack of awareness, availability, and/or affordability, thereby putting hundreds of thousands of fetuses and neonates at risk for Rh disease each year. The global failure to provide this generally acknowledged standard-of-care to prevent Rh disease, even 50 years after its availability, contributes to an enormous, continuing burden of fetal and neonatal disease and provides a critically important challenge to the international health care system.

ABO hemolytic disease of newborn : Does newborn's blood group a risk factor?

BACKGROUND

Due to the marked decline of maternal-fetal rhesus incompatibility, ABO alloimmunization has become the leading cause of the newborn hemolytic disease. It is estimated that 15-25 % of all pregnancies are concerned by ABO incompatibility.

AIM

Neonatal blood group B seems to be more predisposing to acute hemolysis and severe hyperbilirubinemia. We propose to find if the newborn's blood group B represents a risk factor for severe hemolysis and/or severe hyperbilirubinemia.

METHODS

We conducted a comparative study in the pediatrics department "B" of the Children Hospital of Tunis. We collected retrospectively the medical files of the newborn hospitalized for ABO alloimmunization (January 2011 - March 2014), then we compared two groups, OA group with OA alloimmunization and OB group with OB alloimmunization. A significant threshold was fixed to 0.05.

RESULTS

We collected 98 cases of newborn ABO hemolytic disease. Both groups, OA and OB, were similar for the onset of jaundice, age of hospitalization, initial hemoglobin and indirect bilirubin levels. There were no statistically significant difference in the severity of hyperbilirubinemia and the use of exchange transfusion for the two groups. However, transfusion was statistically more frequent in the OB group compared to OA group (81.6‰ vs 10.2‰, p = 0,039, OR=2.9, 95% IC (1.1 - 7.8)).

CONCLUSION

OB alloimmunization seems to induce more active hemolysis than OA one, with no difference for severe hyperbilirubinemia in both groups.

Pregnancy Outcomes Of Consanguinity Among Antenatal Patients Attending Combined Military Hospital Quetta, Pakistan

BACKGROUND

All definitions of consanguinity encompass the basic concept of close blood relation. Highest rates of consanguineous unions are observed for North and Sub Saharan Africa, Middle East, and west, central and south Asia, where 20-50% marriages are consanguineous. In Pakistan, we can hardly find any rigorous research on the pregnancy outcomes of consanguinity except those conducted by Allan Bittles. This study was conducted with the objective to measure statistically if there existed any association of consanguinity with pregnancy outcomes in the form of stillbirths, abortion and Rh-incompatibility.

METHODS

This cross sectional analytical study was conducted at the Obstetrics department of Combined Military Hospital Quetta, Pakistan from 1st November 2017 to 28th February 2018. All pregnant women visiting Out Patient Department were included. Women unwilling to participate or needing emergency intervention were excluded. Sample size, i.e., 384 was calculated using online OpenEpi calculator and simple random sampling technique was applied. A structured interviewer administered questionnaire was used to extract retrospective information. Descriptive statistics, 95% Confidence Intervals, Chi-Square test and Contingency Coefficient were calculated using SPSS Version 20. Results were regarded significant at p<0.05.

RESULTS

Out of 384 study participants, 188 (48.9% with 95% CI:43.9- 53.9%) were married to first cousins. Mean±SD age of the study participants was 27.5±4.8 years. Difference between stillbirth, and abortion among consanguineous unions and nonconsanguineous unions was significant while that of Rh-incompatibility was non-significant..

CONCLUSIONS

Large population based studies are needed before declaring consanguinity as a health problem in our setting.

Prevalence, specificity and risk of red blood cell alloantibodies among hospitalised Hubei Han Chinese patients

BACKGROUND

The prevalence, specificity and risk of red blood cell alloantibodies vary widely among different geographic areas, races, and diseases and according to different methods of study, but no data are available on the Chinese Han population, who were investigated in the present study.

MATERIALS AND METHODS

Antibody screening was conducted among 42,517 hospitalised Hubei Han Chinese individuals using column agglutination technology. Samples that were positive in antibody screening were subjected to antibody identification by the tube test. Clinical data, including gender, age, race, transfusion history and records of alloantibody detection, transfusion reactions or haemolytic disease of the newborn, were collected to analyse the prevalence and specificity of alloantibodies and complications associated with them.

RESULTS

A total of 212 patients with alloantibodies were identified among 42,517 patients, yielding a prevalence of 0.50% in this study. Significantly different prevalence rates were observed according to age and sex. The most frequently identified alloantibodies were anti-E (87/212, 41.0%), anti-D (45/212, 21.2%), anti-M (41/212, 19.3%) and a combination of anti-E and anti-c (13/212, 6.1%). Haemolytic disease was observed in 13 infants with anti-D, three infants with anti-E and one infant with anti-Fy(a) alloantibodies. Delayed haemolytic transfusion reactions occurred in four patients with alloantibodies.

DISCUSSION

In hospitalised Hubei Han Chinese individuals, the overall prevalence of alloantibodies was 0.50%, with anti-E, anti-D and anti-M being the most frequently identified alloantibodies. These results indicate that anti-D and anti-E alloantibodies were major risk factors for haemolytic disease of the newborn or delayed haemolytic transfusion reactions in this study population.

Neonatal hyperbilirubinemia and Rhesus disease of the newborn: incidence and impairment estimates for 2010 at regional and global levels

BACKGROUND

Rhesus (Rh) disease and extreme hyperbilirubinemia (EHB) result in neonatal mortality and long-term neurodevelopmental impairment, yet there are no estimates of their burden.

METHODS

Systematic reviews and meta-analyses were undertaken of national prevalence, mortality, and kernicterus due to Rh disease and EHB. We applied a compartmental model to estimate neonatal survivors and impairment cases for 2010.

RESULTS

Twenty-four million (18% of 134 million live births ≥ 32 wk gestational age from 184 countries; uncertainty range: 23-26 million) were at risk for neonatal hyperbilirubinemia-related adverse outcomes. Of these, 480,700 (0.36%) had either Rh disease (373,300; uncertainty range: 271,800-477,500) or developed EHB from other causes (107,400; uncertainty range: 57,000-131,000), with a 24% risk for death (114,100; uncertainty range: 59,700-172,000), 13% for kernicterus (75,400), and 11% for stillbirths. Three-quarters of mortality occurred in sub-Saharan Africa and South Asia. Kernicterus with Rh disease ranged from 38, 28, 28, and 25/100,000 live births for Eastern Europe/Central Asian, sub-Saharan African, South Asian, and Latin American regions, respectively. More than 83% of survivors with kernicterus had one or more impairments.

CONCLUSION

Failure to prevent Rh sensitization and manage neonatal hyperbilirubinemia results in 114,100 avoidable neonatal deaths and many children grow up with disabilities. Proven solutions remain underused, especially in low-income countries.

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.

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 cell antibodies 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.

[Analysis and perinatal outcome after intravascular transfusion]

INTRODUCTION

the leading cause of fetal anemia is Rh isoimmunization. The timely diagnosis by ultrasound and intravascular transfusion improves the prognosis.

OBJECTIVE

to evaluate the increase in hemoglobin in the fetus and correlate the red cell transfusion volume with elevation of hemoglobin and perinatal outcome.

PATIENTS AND METHODS

prospective, case series study. We included 17 patients with fetal anemia detected by measuring the peak systolic velocity of middle cerebral artery and determination of fetal hemoglobin before and after cordocentesis. After confirmation of fetal anemia (Hb <10 g/dL), was held fetal transfusion with 50 mL/kg estimated fetal weight, with packed red blood cells type O Rh negative.

RESULTS

In 17 cases fetal anemia was diagnosed, of which 11 (64%) had Rh isoimmunization and 6 (36%) were not immune. The 17 cases received 27 intravascular transfusions, in 75% hemoglobin rose to 10 g/dL, 45% in the first transfusion, 25% in the second and 10% in the third transfusion. Fetal hemoglobin between before and after transfusion was 6.5 and 12.9 g/dl, respectively (p<0.001) and allowed to continue the pregnancy from 3 to 12 weeks from the first transfusion. There were 4 deaths (2 stillbirths and 2 neonatal), but only one was related to the procedure. the survival rate was 76%, mortality in the presence of hydrops was 30% and no deaths in patients without hydrops.

CONCLUSIONS

Mortality in fetal anemia was 23.6% and only one case was related to intravascular transfusion. In cases of survival to birth, pregnancy lasted >30 weeks gestation. Hemoglobin rose from 27 to 300% of the initial fetal hemoglobin. The presence of fetal hydrops significantly increases mortality.

Is antibody screening in Rh (D)-positive pregnant women necessary?

OBJECTIVE

Hemolytic disease of the fetus and of the newborn can be caused by incompatibility of maternal and fetal erythrocytes for Rh (D) or other blood type antigens. Routine antibody screening is advocated in all pregnant women, irrespective of whether they are Rh (D)-positive or Rh (D)-negative, to look for clinically significant alloantibodies other than Rh (D) that might cause hemolytic disease of the newborn. The purpose of this study was to assess the incidence of blood type antibodies other than Rh (D) in pregnant women attending for prenatal care in a typical urban population.

METHODS

A retrospective analysis was undertaken of the charts of all pregnant women followed throughout their entire pregnancy at our Women's Health Center from 1 January 1999 to 30 April 2002.

RESULTS

There were 1265 pregnant women included in the study: 465 had blood type A (36.7%), 269 type B (21.3%), 424 type O (33.5%) and 107 type AB (8.5%). A total of 1156 were Rh (D)-positive (91.4%) and 109 were Rh (D)-negative (8.6%). Of the Rh (D)-positive women, 522 (41.3%) underwent routine antibody screening in the first trimester. Only one woman (0.2%) had a positive antibody screen. Of the 109 Rh (D)-negative women, one (0.9%) had a positive third trimester screen with a negative first trimester screen.

CONCLUSION

Routine antibody screening of Rh (D)-positive women is probably not warranted from a clinical cost-benefit perspective.

Should we continue screening rhesus D positive women for the development of atypical antibodies in late pregnancy?

OBJECTIVE

The purpose of this study was to calculate the incidence of the new development of atypical antibodies (other than anti-rhesus D) in women attending for antenatal care, and to assess the clinical impact and cost-effectiveness of a second test to detect these antibodies.

METHOD

A three-year retrospective analysis was undertaken to calculate the number of rhesus positive women who developed new antibodies in the last trimester of pregnancy.

RESULTS

Of 13,143 rhesus positive women, 20 (0.15%) developed new antibodies; fetal outcome was not compromised in any of these cases.

CONCLUSION

Repeat testing in late pregnancy would appear an unnecessary expense in our population.

JAL (RH48) blood group antigen: serologic observations

BACKGROUND

JAL (RH48) is a low-prevalence antigen in the Rh blood group system and anti-JAL has caused hemolytic disease of the newborn. JAL is associated with either a haplotype carrying depressed C and e antigens or one carrying depressed c and e antigens. Blood samples from JAL+ people were tested, published serologic findings were confirmed, serologic studies were extended to include expression of other Rh antigens, and the antibody specificities produced by three sensitized JAL+ probands are reported.

STUDY DESIGN AND METHODS

Red blood cell (RBC) samples from 17 (12 probands) JAL+ persons were tested by hemagglutination using standard methods.

RESULTS

RBCs from both the Caucasian JAL+ probands had the (C)(e) haplotype and weakened C, e, hr(B), and hr(S) antigens. JAL+ samples from black persons had the (c)(e) haplotype and expressed weakened c, e, f, V, VS, hr(B), and hr(S) antigens. Plasma from three sensitized c+e+ JAL+ probands contained alloanti-c, alloanti-e, or alloantibody of apparent anti-Rh17 specificity. This study shows that this alloanti-Rh17-like antibody recognizes the high-prevalence antigen antithetical to JAL that has been named CEST.

CONCLUSIONS

The presence of the JAL antigen has a quantitative (weakening) effect on the expression of C, e, hr(B), and hr(S) antigens in Caucasian persons and of c, e, f, V, VS, hr(B), and hr(S) antigens in people of black African ancestry. A qualitative effect also was demonstrated by the presence of alloanti-c or alloanti-e in the plasma of two transfused c+e+ patients and by an antibody (anti-CEST) that recognizes the high-prevalence antigen antithetical to JAL.

Incidence of haemolytic disease of the newborn in Harare, Zimbabwe

BACKGROUND

Haemolytic Disease of Newborn is responsible for a number of neonatal deaths and complications worldwide. Its incidence in Zimbabwe is not clearly understood.

OBJECTIVE

To find out incidence of Haemolytic Disease of Newborn in Harare and ability to identify antibodies associated with HDN.

METHODS

A retrospective cross sectional study at the Parirenyatwa Group of Hospitals and National Blood Service, Zimbabwe (NBSZ). We studied 22493 infants at Parirenyatwa Hospital during the 1995-1997 and 2002-2003 periods. The main outcome measures were ABO and Rh blood group results, Direct Antiglobulin Test and Maternal Antibody Screening and Identification Results were obtained from the NBSZ.

RESULTS

One hundred and ninety-one (0.85%) infants had Haemolytic Disease of Newborn. One hundred and sixty-three (85.34%) of these were due to anti-AB, twenty five (13.09%) were due to anti-D and three (1.57%) due to anti-Kell. Incidence of Haemolytic Disease of Newborn during 1995-1997 and 2002-2003, were 0.93% and 0.64%, respectively (p = 0.014). ABO Haemolytic Disease of Newborn showed a statistically significant difference during the two periods (p = 0.003). Rhesus Haemolytic Disease of Newborn showed no statistically significant difference during same periods (p = 0.317).

CONCLUSION

The incidence of Haemolytic Disease of Newborn at Parirenyatwa Hospital is comparable with that found in other countries. It is recommended that K antigen be included in the pretransfusion testing to avoid anti-K related Haemolytic Disease of Newborn.

Impact of Specific Medical Interventions on Reducing the Prevalence of Mental Retardation

OBJECTIVE

To explore the impact of medical interventions on reducing the prevalence of mental retardation (MR) in the United States over the last 50 years.

DESIGN

We reviewed the medical literature and other data from 1950 to 2000 to construct estimates of the general and condition-specific prevalence of MR in the United States over time. We further explored the existing literature to document historically important influences on condition-specific prevalence, including the year that an effective intervention was introduced, the likelihood of success of the intervention, and the availability of such interventions nationwide. Specific conditions included congenital syphilis, Rh hemolytic disease of the newborn, measles, Haemophilus influenzae type B meningitis, congenital hypothyroidism, phenylketonuria, and congenital rubella syndrome.

SETTING

Twentieth-century North America.

PARTICIPANTS

Children with MR or 1 of the 7 specific conditions listed earlier.

MAIN OUTCOME MEASURES

Case-specific and general prevalence of MR from 1950 to 2000.

RESULTS

The prevalence of MR caused by a number of specific medical conditions has decreased sharply over the last 50 years. However, the incidence of each of these conditions is relatively low, and cases of MR due to these conditions represent, at most, 16.5% of the total number of cases of MR in 1950.

CONCLUSION

Although specific medical interventions have prevented thousands of cases of MR, their contribution to the overall prevalence of MR is relatively small.

The pregnant Rhesus negative Nigerian woman

OBJECTIVE

Alloimmunisation to Rhesus D (RhD) is a major factor in perinatal morbidity and may result in the compromise of the woman's obstetric career. In Nigeria accurate population based studies to determine the prevalence of Rhesus negative women and the incidence of alloimmunisation are lacking, hence we undertook to study pregnancy outcome in Rhesus negative women.

METHOD

We studied retrospectively sixty-seven RhD negative women over a two year period; information was obtained from the case-file of all pregnant women who presented to the ante-natal clinic and were identified as Rhesus negative. This was corroborated with the blood bank record over the same period.

RESULT

Forty per cent of these were nulliparae with an average of 0.5 abortions. Only 20% had the blood groups of their husbands documented, and only four babies born to these women had their Rhesus group recorded. Six of the babies appeared to have been severely affected by Rhesus isoimmunisation. Three of these had an exchange blood transfusion (EBT); all who had an EBT had a satisfactory outcome. Out of the other three, there were two neonatal deaths and one fresh stillbirth. Fourteen babies had neonatal jaundice with a mean bilirubin level of 6 mg/dl, all of which were mainly unconjugated. Evidence for the administration of anti D was obtained in only three patients; all had one ampoule (dose in i.u and/or _g not stated) administered within 72 hr.

CONCLUSION

This preliminary study has shown that isoimmunisation due to Rhesus incompatibility is poorly studied among Nigerian women with many questions unanswered; therefore there is an urgent need for a management protocol for this condition, which will include both the clinicians and the laboratory physicians.

Partial D, weak D types, and novel RHD alleles among 33,864 multiethnic patients: implications for anti-D alloimmunization and prevention

BACKGROUND

The D antigen includes category D, partial D, and weak D types, which are important because anti-D alloimmunization can occur in some but not all persons that express a variant RHD allele. At present, there is little prospective information on the prevalence of D variants among obstetric patients and potential transfusion recipients.

STUDY DESIGN AND METHODS

The RHD alleles were prospectively examined in a large patient population identified on the basis of a difference in anti-D reactivity between two reagents.

RESULTS

Fifty-five discrepancies (0.96% of D-) were noted among 33,864 ethnically diverse patients over 18 months, of which 54 represented mutated RHD alleles. Seven obstetric patients were assigned D- status based on serology; only 1 patient had a partial RHD allele. Ten of 25 (36%) obstetric patients and 4 of 6 (67%) female potential transfusion recipients of childbearing age or younger were assigned D+ status, and they expressed a D variant known to permit anti-D alloimmunization. In total 20 RHD alleles were identified including category, DVa or DVa-like alleles (n = 7), DAR (n = 8), and four novel RHD alleles including two new DAU alleles.

CONCLUSION

Given the complexity of D antigen expression, it is concluded that some clinically important D variants identified by standard serologic analysis phenotype as D+ and are potentially at risk for the development of anti-D.

[Foetomaternal erythrocyte incompatibilities: from immunohaematologic surveillance of pregnant women to haemolytic disease of the newborn]

Despite the generalization of prevention measures against foetomaternal alloimmunization with anti-D immunoprophylaxis since 1970s, retrospectively 30 years later, its complications (new-born child's severe haemolytic disease, foetal death by anemia or nuclear icterus by bilirubin encephalopathy) have not disappeared. At the same time, alloimmunizations against antigens other than D increase with no possible prevention. As part of the set up in France of regional files analysing and making an inventory of serious foetomaternal incompatibilities requiring in utero or neonatal transfusion, we felt the need to synthesize current data, biological profiles (early screening of erythrocytic alloimmunization and its follow up during pregnancy, father's immunohaematologic status, evaluation of in utero immune haemolysis and impact of new non invasive techniques of diagnosis-RH1 foetal genotypage from ADN foetal of RH1--mothers' maternal plasma), clinical and paraclinical data (evaluation of foetal haemolysis by echography, recording of foetal movements and foetal cardiac rhythm), therapeutic indicators (in utero foetal transfusions or exsanguinotransfusions, neo and postnatal transfusions or exsanguinotransfusions, induced premature labour, newborn's intensive continue phototherapy and Rhesus immunoprophylaxis) in order to enable medical and paramedical professionals to carry out the specific supervision of pregnancies with foetomaternal incompatibility, the in utero, neo- and postnatal treatment of child and the efficient therapeutic prevention of anti-D alloimmunization, in a cooperative way.

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

OBJECTIVE

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

STUDY DESIGN

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

RESULTS

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

CONCLUSION

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

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

OBJECTIVE

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.

METHODS

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.

RESULTS

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%.

CONCLUSIONS

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.

Haemolytic disease of the newborn due to maternal irregular antibodies in the Chinese population in Taiwan

From 1991 to 2000, amongst 23,886 full-term healthy Chinese babies delivered at our hospital, 2615 babies developed neonatal hyperbilirubinaemia. After excluding other causes of hyperbilirubinaemia and identifying the irregular antibodies, 15 cases of haemolytic disease of the newborn (HDN) due to maternal irregular antibodies were diagnosed; three cases were born in our hospital and 12 cases were referred. Amongst these 15 babies, six cases had HDN due to anti-E, three cases due to anti-E + c, three cases due to anti-D, one case due to anti-c and two cases due to 'Mi' antibodies reacting with MiIII phenotype cells (anti-Hil and anti-Mur). Although there were four cases of hydrops fetalis, only one of the patients expired. The prevalence of HDN caused by maternal irregular antibodies has been estimated to be 0.01%. Therefore, routine prenatal screening for irregular antibodies was not rational in the Chinese population in Taiwan. Anti-E and anti-E + c were the important irregular antibodies resulting in HDN. Although few cases of HDN due to anti-'Mi' have been reported, Anti-'Mi' is significant in regions with a high prevalence of the MiIII phenotype.

Increased fetal iron load in rhesus hemolytic disease

There is little information about the iron overload caused by hemolysis in fetuses affected with rhesus hemolytic disease (RHD). The authors therefore studied the iron load in RHD by measuring cord blood ferritin levels in babies affected with RHD and gestational age- and weight-matched controls. Cord blood ferritin levels were higher in babies with RHD. Intrauterine transfusions did not affect the ferritin status of the babies with RHD and there was no correlation between hemoglobin and ferritin levels. The results indicate that there is an increased intrauterine iron load in babies with RHD, independent from intrauterine transfusions and rate of hemolysis.

Is antenatal antibody screening worthwhile in the Zimbabwean population?

OBJECTIVES

To determine the incidence of clinically significant allo-antibodies in antenatal care (ANC) patients, and make recommendations on laboratory management of such cases in similar settings in Zimbabwe.

DESIGN

A retrospective study.

SETTING

Harare Central Hospital, a tertiary medical centre in Harare.

SUBJECTS

Patients attending the ANC clinic at Harare Central Hospital.

MAIN OUTCOME MEASURES

Blood group tests, allo-antibody screen, development of haemolytic disease of the newborn.

RESULTS

3,000 patients were grouped and screened and 96.7% were found to be Rhesus positive, 0.5% were Rhesus Du positive and 2.8% were Rhesus negative. An overall antibody incidence of 1.7% (n = 50) was obtained, 1.0% (n = 30) of which were strongly positive and 0.7% (n = 20) were so weakly positive so that no antibodies could be identified. Antibodies identified from those patients with strongly positive antibody screen were anti-D 13.3% (n = 4), anti-E 6.7% (n = 2), anti-Jsb 3.2% (n = 1), anti-Lea 23.3% (n = 7) and anti-Leb 20% (n = 6). Antibodies of unknown specificity were detected from 20% (n = 6) of the patients. Four (13.3%) of the specimens were insufficient for antibody identification. Clinical records of those patients with a strongly positive antibody screen were examined and anti-D and anti-Jsb were observed to have caused severe to fatal Haemolytic Disease of the Newborn (HDN). The four anti-D positive cases resulted in two still births and two jaundiced babies. The single anti-Jsb positive antibody case resulted in an intra-uterine death. Antibodies that are generally considered of no clinical significance did not cause HDN in this study.

CONCLUSION

Anti-D remains the most important allo-antibody causing HDN, regardless of the availability of anti-D immunoglobulin for prophylaxis. Only Rhesus D negative women and those who have clinically significant antibodies need have repeat antibody screens during the rest of the pregnancy. In line with the current policy of screening all patients at booking, the policy on repeats is not clear and was not evident in this study.

[Diagnostic and therapeutic proceedings in pregnancies with blood group incompatibility: A retrospective analysis over 30 years]

PURPOSE

To examine the development during the past 30 years of diagnostic and therapeutic procedures in pregnancies with blood group incompatibility.

PATIENTS AND METHODS

We evaluated 193 pregnancies with maternal red blood alloimmunisation treated at our hospital. At least one amniotic fluid spectrophotometry was performed.

RESULTS

We observed a reduced average age of the patients, a reduced parity and an increase in the number of amniotic fluid examinations per pregnancy in the course of time. Amniotic fluid examinations tended to be performed earlier in pregnancy. Gestational time was reduced, the rate of spontaneous vaginal deliveries remained unchanged. The proportion of anti-D-alloimmunisation decreased in relation to other antigens and the severity of the cases increased (assessed according to the findings of the spectrophotometric amniotic fluid examinations performed while using the semiquantitative method of Liley). The haemoglobin values of the newborn, without intrauterine transfusions, were unchanged and the number of intrauterine deaths decreased. The rate of postnatal transfusions decreased dramatically, whereas the rate of phototherapeutic approaches increased.

CONCLUSION

The spectrum of the antigens causing fetal haemolytic disease has changed during the last 30 years and so have the diagnostic and therapeutic procedures.

[Foetal-maternal alloimmunizations in the South-East area of the Venice province]

BACKGROUND

This study report the results obtained in a retrospective analysis of the foetal-maternal alloimmunizations observed from 1993 to 1999 in the South-East area of the Venice province.

METHODS

The data concerning 17,000 pregnancy observed in this area from 1993-1999 have been collected. For each pregnancy data concerning maternal ABO, Rh, Kk and IAT as well as foetal ABO, Rh, Kk and DAT were available. Further data (mainly antibodies concentration and specificity) were available if a foetal-maternal alloimmunization was detected and if transfusional support was given after the birth.

RESULTS

The authors observed 465 alloimmunizations (prevalence 2.7%): 381 (82%) of these were due to an ABO foetal-maternal incompatibility, 23 due to D incompatibility and the other 61 due to other blood groups antigens. Only 6 cases needed transfusional support: 5 exchange transfusion (a patient needed 2 exchanges) and a delayed transfusion.

CONCLUSIONS

Foetal-maternal alloimmunizations are today a rare but not exceptional event (about 3% of pregnancy), the great majority of these alloimmunizations are due to an ABO incompatibility. Despite the prevention of alloimmunization in D negative women by using Rh immune globulin, anti-D alloimmunization is still observed. A great number of other blood groups antigens are involved in foetal-maternal alloimmunization mainly within the Rh system (CcEe, etc.). In the authors' experience the great majority of foetal-maternal alloimmunizations were clinically silent, only 6 cases (1.3% of patients with a positive DAT) needed transfusional therapy.

Prognostic value of screening for irregular antibodies late in pregnancy in rhesus positive women

BACKGROUND

To evaluate the prognostic value of screening for irregular antibodies late in pregnancy (third trimester) in rhesus positive women. Only those cases where irregular antibodies have not previously been demonstrated during routine screening in the first trimester with regard to clinically relevant complications in the newborn, were studied.

MATERIALS AND METHODS

All women living in Frederiksborg county and giving birth in 1996 (n = 4216) were assessed for inclusion in the study. This was done by gathering the files at the Hillerød and Hørsholm Hospitals' blood banks for antibody test results. Six hundred women were excluded because of the lack of either the rhesus type or the late antibody test.

RESULTS

Of the 3616 women, 3046 were rhesus positive, and 3012 of these had a negative first trimester screen test. Fifteen of the 3012 women later developed irregular antibodies in the third trimester, and were included in the study. This corresponds to only 0.5%, and none of these cases entailed perinatal complications for the mother or the child.

CONCLUSION

Routine screening of rhesus positive pregnant women in the third trimester is not rational from a cost-benefit perspective, if the only purpose is to prevent hemolytic disease of the newborn.

The clinical outcome of non-RhD antibody affected pregnancies in Northern Ireland

We assessed the clinical outcome of pregnancies with non-Rh-D antibody in Northern Ireland using retrospective case note review. During the study period (April 1999- March 2000) 186 women with clinically significant antibodies were identified from the records of the antenatal laboratory of the Northern Ireland Blood Transfusion Service. Eighty-five women were included in the study using the criteria mentioned above. None of the fetuses required intrauterine transfusion during this period. One baby required exchange transfusion, three were given top-up transfusions and 17 had phototherapy. Nine babies with a positive direct antiglobulin test (DAT) received no treatment. The incidence of anti-Kell could be reduced by transfusing Kell negative red cells to premenopausal women. It is important that all pregnant women are tested at least twice in their pregnancy to detect the antibodies formed late in the pregnancy. It is useful to formulate a standard protocol for antenatal interventions. Non Rh-D antibodies can cause significant anaemia for up to six weeks in the neonatal period, hence early detection of maternal antibodies is important so that the neonates are followed up for an appropriate length of time.

The fetal and neonatal outcomes of Rhesus D antibody affected pregnancies in Northern Ireland

It has been suggested that routine antenatal prophylactic anti-D should be introduced for prevention of Rhesus D (RhD) haemolytic disease. Before making changes to the current prevention program it is important, therefore, to have up-to-date data on affected infants. Pregnant women with anti-D antibodies between September 1994 and February 1997 were identified by the Northern Ireland Blood Transfusion Service. The records of 124 women and 130 babies were examined. 26% of planned deliveries occurred in hospitals without paediatric cover. Rhesus isoimmunisation affected 78 babies. Fifty-nine infants were admitted to one of seven neonatal units. There were 2 stillbirths and 1 neonatal death. Two infants have severe neurodevelopmental delay. There is still significant morbidity associated with RhD haemolytic disease. Care for RhD affected pregnancies should be centralised to guarantee training opportunities and maintenance of expertise. The current management of these pregnancies should be re-examined before changing the Rhesus prevention program.

[The incidence of irregular antibodies in pregnancy: a prospective study in the region of the 's-Hertogenbosch]

OBJECTIVE

To determine the incidence and clinical relevance of irregular erythrocyte antibodies (IEA), in multiparous women and in primigravidal with a history of blood transfusion.

DESIGN

Prospective longitudinal cohort study.

METHODS

In the 's-Hertogenbosch area, the Netherlands, both primigravidae with a previous blood transfusion and multiparous women were tested for IEA in addition to the regular blood tests during the first trimester of pregnancy. If IEA were discovered, the partners were tested for the presence of the antigen involved. Blood samples of children of positive fathers were tested immediately post partum for signs of haemolytic disease of the newborn (HDN).

RESULTS

During a 2.5-year period (August 1995-January 1998) a total of 2392 pregnant women were screened for IEA: 2204 multiparous women and 188 primigravidae women. In 65 women 81 IEA were discovered. In the group of 30 children positive for the antigen involved, 12 (40%) had clinical symptoms of HDN; intrauterine death was diagnosed once, one child died immediately after delivery. One child had signs of hydrops fetalis and two children needed an exchange transfusion. Phototherapy and/or regular blood transfusion were given to 7 children. Most cases of HDN were caused by anti-D, anti-Kell and anti-c antibodies.

CONCLUSION

Non-RhD-IEA were found in 1.6% of pregnant women screened. First-trimester screening for IEA is recommended as it can be of help in early diagnosis and treatment of HDN.

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.

[Hemolytic disease of the newborn and irregular blood group antibodies in the Netherlands: prevalence and morbidity]

OBJECTIVE

To inventory prevalence and morbidity of haemolytic disease of newborn caused by irregular anti-erythrocyte antibodies other than antirhesus-D.

DESIGN

Prospective registration study.

METHOD

All paediatricians (n = 380) in general hospitals and contact persons (n = 79) in university hospitals were asked for monthly reports of clinical cases of haemolytic disease of newborn during 2 years (1996-1997).

RESULTS

Response was 97%. A total of 130 reports were received in two study years, 49 of which could not be confirmed as non-RhD-non-AB0 antagonism. In the group of which the transfusion history was known (n = 60), 29 pregnant women (48%) had received transfused blood at some time. Of the antibodies found, anti-c, anti-E and anti-K were the most frequent. The direct antiglobulin test was positive in 61 of the 81 cases, negative in 10 cases, while in 10 cases it was unknown or false-negative due to earlier intrauterine transfusions (in three neonates). The highest bilirubin levels recorded were 572, 559 and 520 mumol/l (all three with maternal anti-c antagonism). Therapeutic data were known concerning 80 of the 81 newborn: 21 (16%) received no treatment, 24 (29%) only phototherapy and the others--in addition to phototherapy if any--also blood transfusion, exchange transfusion or intrauterine transfusion, or a combination of these.

CONCLUSION

It was calculated that the actual prevalence of irregular anti-erythrocyte antibodies in Dutch pregnant women probably amounts to approximately 0.25%. This finding may possibly be confirmed since starting 1 July 1998 all pregnant women in the country are screened for the presence of these antibodies. It is recommended that girls and women in the reproductive age group should receive primary prevention of development of irregular anti-erythrocyte antibodies by application of a selective blood transfusion policy, taking into account the occurrence of the antigens c, E and K.

Epidemiology of clinical hyperbilirubinaemia in Al Ain, United Arab Emirates

All infants born at Al Ain Hospital, United Arab Emirates between 1 January and 30 June 1995 who developed clinically relevant hyperbilirubinaemia defined as jaundice requiring investigation and treatment were prospectively studied. Of the 2300 live births, 85 (3.7%) developed hyperbilirubinaemia. Of these, 22 were premature, 22 had ABO haemolytic disease of the newborn, eight had G6PD deficiency (Mediterranean), seven had breast-milk jaundice, five were born to mothers with diabetes mellitus and one had Rh incompatibility. No specific factor was identified in 20 (24%). Significant differences in the distribution of diagnostic categories were found among the major ethnic groups in the population studied. This first study of the epidemiology of clinically relevant hyperbilirubinaemia in this community identified locally relevant risk factors and highlighted areas of health care which, if modified, might reduce the incidence of hyperbilirubinaemia.

The decline in Rh hemolytic disease: should Rh prophylaxis get all the credit?

OBJECTIVES

This study sought to quantify the magnitude of Rh disease reduction occurring secondary to Rh prophylaxis and other determinants.

METHODS

Outcomes considered included maternal Rh sensitization, neonatal Rh disease, and perinatal deaths from Rh disease. Analysis was based on Poisson regression modeling of ecological data from Manitoba, Canada, and conditional probability modeling.

RESULTS

The ecological analysis showed that changes in birth order and Rh prophylaxis resulted in 24% (95% confidence interval [CI] = 1% 42%) and 69% (95% CI = 61%, 76%) decreases, respectively, in Rh sensitizations (D and non-D) in Manitoba between 1963 and 1988. Rh prophylaxis and nonprogram factors were responsible for 83% (95% CI = 44%, 95%) and 78% (95% CI = 42%, 91%), respectively, of the reduction in perinatal deaths from Rh disease. Similar results were obtained with conditional probability modeling, which also provided estimates for the effects of changes in abortion rates and racial composition.

CONCLUSIONS

In addition to Rh prophylaxis, changes in other determinants were responsible for an important fraction of the decline in Rh disease. These results provide a historical perspective on the conquest of Rh disease and also have important implications for public health policy, particularly in developing countries.

[Results of postpartum Rhesus prophylaxis 1967 to 1990]

INTRODUCTION

The aim of the study is to analyse the benefit of rh-prophylaxis at the Universitäts-Frauenklinik Köln from 1967 to 1990.

MATERIAL AND METHOD

During that period 28,761 births, of whom 2602 were non-sensitized rh-negative mothers with a rh-positive child (9.04%), were assessed. 2223 mothers received rh-prophylaxis, in 379 cases rh-prophylaxis was omitted particularly within the first 4 years of the study period, due to a limited provision of anti-D immunoglobulines. From 1972 onwards postnatal rh-prophylaxis was omitted in only 3%. In 14.5% of the 379 women without rh-prophylaxis contamination of the maternal circulation system with HbF cells was confirmed by the Kleihauer-Betke-Test. In 98.4% of the cases rh-prophylaxis was performed postnatally within the first 72 hours.

RESULTS

During the study period the initial dosage of IgG anti-D was set at 55 - 150 microgram i.v. (n = 217) and later increased to 150 - 250 microgram i.v. (n = 1109) and finally to 300 - 330 microgram i.m. (n = 897). After rh-prophylaxis presence of HbF cells in the maternal circulation was found in 5.5% of the mothers of group 1, in 2.1% of the second group and in 1.1% of the third group. In the group of mothers without rh-prophylaxis 69 had a second delivery and rh-sensitsation was found in 7.3% of these cases. Of 537 women having received rh-prophylaxis who delivered a second rh-positive child, 9 (1.7%) showed rh-sensitisation. of the 352 women with rh-incompatibility 8 (2.3%) had already been sentisized during their first pregnancy.

CONCLUSIONS

The study confirms that postnatal application of anti-D immunoglobulins is effective to a great extent but does however not completely exclude rh-sensitisation. Furthermore, we recommend the additional prenatal rh-prophylaxis as introduced by the German maternity regulations since 1990.

The prevalence of red cell antibodies in pregnancy correlated to the outcome of the newborn: a 12 year study in central Sweden

BACKGROUND

All maternal red cell antibodies found during pregnancy in a 12 year period have been compiled. The efficacy of the current antenatal screening and management programme has been ascertained by reviewing the outcome of all newborns to these immunized mothers.

METHOD

Patient selection was carried out by computerised searching for all known records of registered antibodies during the study period. Each mother's obstetric record and her baby's hospital file was studied and relevant clinical treatment and laboratory data on both mother and child was recorded and analysed.

RESULTS

Eight hundred and twenty-one alloantibodies were detected in 629 immunized pregnant women with 753 fetuses. An overall antibody incidence of 0.57% was observed which included 373 clinically significant antibodies found in 261 mothers (0.24%). Multiple antibodies were present in 8.2% of all samples. Anti-D, by itself or in combination with other Rh-antibodies, caused more severe forms of hemolytic disease of the newborn (HDN) with 46% of all Rh-positive babies having phototherapy and 29% having exchange transfusion. Three of 18 Fya-positive infants required phototherapy and one required exchange transfusion and in the 16 Kell-positive babies, three required phototherapy and one required exchange transfusions.

CONCLUSIONS

Few antibodies to blood group antigens other than those in the Rhesus system were found to cause severe HDN. Antibodies that are generally considered non-significant did not cause HDN in this study. All antibodies that induced HDN were detected in time so that adequate measures could be taken to reduce the effects in the newborn. The antenatal screening and management programme currently in use is considered to be reliable.

A 'new' low-incidence red cell antigen, WARR: unique to Native Americans?

Investigation of a mild case of hemolytic disease of the newborn has led to recognition of a 'new' low-incidence red cell antigen, WARR (ISBT No. 700.55). Data gleaned from two kindreds, both with Native American heritage, exclude WARR from the MNS, Lutheran, Lewis, Duffy, Kidd, Xg, Chido/Rodgers, Kx and Gerbich blood group systems. Serologic or genetic evidence suggests it is not part of the Kell or Yt systems.