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.

Does strengths of a positive direct antiglobulin test predicts the need for phototherapy and duration of phototherapy? - a single center, retrospective study.

BACKGROUND: Use of Direct Antiglobulin test (DAT) in management of neonatal hyperbilirubinemia is conflicting. OBJECTIVE: whether strength of positive DAT predicts the need for phototherapy, duration of phototherapy and need for major interventions. METHODS: We retrospectively collected data on all DAT positive neonates with birth gestational age ≥32 weeks over six years (2014-2019). Data regarding blood group, DAT and clinical details were obtained from a hospital database. We also collected data on serial hemoglobin and other relevant laboratory parameters. We also collected data on infants receiving major interventions such as exchange transfusion, in-utero transfusion, immunoglobulins, and postnatal transfusion for the duration of the study period. All of these infants were electronically followed up for a period of 6 weeks. This study was approved by institutional audit authority. All the statistics were performed using SPSS software. RESULTS: Out of 1285 DAT tests performed, only 91 infants were positive (7%), and 78 DAT positive infants were available for analysis. There were 54 infants with DAT (1+), 15 infants with DAT (2+), 7 infants with DAT (3+) and 2 infants with DAT (4+). There was no significant statistical difference in terms of need for phototherapy, duration of phototherapy, need for major interventions and hemoglobin levels at different time points between the groups (DAT 1+ Vs DAT ≥2+; DAT ≤2+ Vs DAT >2). A Total of 10 infants received major intervention, with one infant receiving all three interventions (DAT 3+ with significant maternal antibodies), 2 additional infants (both DAT1+) received exchange transfusion, 6 additional infants received immunoglobulin (2 infants: DAT 2+; 4 infants: DAT 1+) and one additional infant (DAT 1+) with significant maternal antibodies received a postnatal transfusion. CONCLUSION: Strength of a DAT did not predict the need for phototherapy, duration of phototherapy, and the need for major hemolysis related intervention in the first 6 weeks of life.

Clinical value of combination detection of direct antiglobulin test and serum albumin globulin ratio in severe hyperbilirubinemia caused by ABO hemolytic disease of the newborn.

Background To explore of a combination of antiglobulin test(DAT) and albumin globulin ratio(AGR) could predict the severity of ABO hemolytic disease of the newborn(ABO-HDN).Methods The measurement of DAT, AGR and combination detection of DAT and AGR was done to predict severe ABO-HDN hyperbilirubinemia in 270 full-term infants based on whether the infants received transfusions of blood components. The infants were divided into three groups according to the results of DAT and ARG and compared the differences of phototherapy day and hospitalization day of the three groups.Results Of the 270 cases enrolled in this study, 69 infants were DAT positive. Peak total bilirubin, AGR, and positive DAT were independently associated with the need for blood components transfusion. ROC curve analysis for blood components transfusion showed that DAT cutoff value >± with a sensitivity of 39.4% and a specificity of 83.9%, AGR cutoff value <2.05 with a sensitivity of 54.1% and a specificity of 85.7%, and combination detection of DAT and ARG with a sensitivity of 62.1% and a specificity of 91.2%. The AUCs for DAT, AGR, and combination detection of DAT and AGR were .621, .740, and .750 respectively. The phototherapy day and hospitalization day were significantly longer in group of AGR <2.05 and DAT >± than that of a group of AGR <2.05 and group of DAT >±.Conclusions DAT and ARG could be early predictors for the severity ABO-HDN hyperbilirubinemia and combination detection of DAT and AGR could further increase its predictive value.

Hemolytic disease of the fetus and newborn mediated by anti-Dia in a U.S. hospital.

Dia is one of the most clinically significant low-prevalence antigens in the Diego blood group system, since antibodies to Dia have, albeit rarely, been implicated in hemolytic transfusion reactions and hemolytic disease of the fetus and newborn (HDFN). Given the geographical association, most anti-Dia HDFN cases have been reported in Japan, China, and Poland. We describe a case of HDFN in a neonate born to a 36-year-old G4P2012 woman of self-identified Hispanic ethnicity and of South American descent with multiple negative antibody detection tests in a U.S. hospital. Upon delivery, a cord blood direct antiglobulin test was positive (3+ reactivity), and neonatal bilirubin levels were moderately elevated, but phototherapy and transfusion were not required. This case highlights a rare, unexpected cause of HDFN in the United States secondary to anti-Dia, given the near-universal absence of this antigen and antibody in most U.S. patient populations. The case also demonstrates the need for awareness of antibodies to antigens that are considered "low-prevalence" in most populations but that might be encountered more frequently in specific racial or ethnic groups and may require more extensive testing.

Rates of phototherapy among ABO-incompatible newborns with a negative direct antiglobulin test.

OBJECTIVE: We analyze phototherapy rates after implementation of a Hyperbilirubinemia Clinical Pathway (HCP), which placed full-term ABOi DAT negative newborns on the low risk phototherapy nomogram, rather than medium risk, as previously done. STUDY DESIGN: A chart review was performed for ABOi newborns born ≥36 weeks gestation between January 2020 and October 2021. Primary outcome measures were rates of phototherapy across pre- and post-intervention groups and among DAT negative newborns. RESULTS: There was an increased proportion of newborns assigned to the low risk curve after the intervention. There were no significant differences in phototherapy rates among the intervention groups, although there was a non-significant decrease in phototherapy rates among DAT negative newborns after the intervention. There were no increases in adverse outcomes. CONCLUSIONS: Providers adhered to the guidelines after implementation of the HCP. ABOi DAT negative newborns can be viewed as low risk for hyperbilirubinemia requiring phototherapy.

Neonatal hemolytic disease due to anti-Diegoa antibody: a case report.

BACKGROUND: The Diegoa antigen commonly occurs in certain Asian and South American Indian populations. In general, hemolysis caused by anti-Diegoa antigen is not severe, and exchange transfusion is rarely needed. Here, we report a neonate with moderate hemolytic disease caused by anti-Diegoa antigen in the Baoji area of China. CASE PRESENTATION: A 39-week gestation male newborn of Han nationality was delivered by second cesarean section because of scarred uterus. The newborn's birth weight was 3700 g with an Apgar score of 9. Four hours after delivery, transcutaneous bilirubin test revealed a level of 17 mg/dl. After 23 hours, the neonate developed anemia and hyperbilirubinemia. Bacterium, virus and other pathogens, as well as tests for arcuate and glucose-6-phosphate dehydrogenase, were all negative. Direct antiglobulin test of the neonate was positive. Diegoa antigens of the baby and his father were positive, while his mother was negative. The newborn was successfully cured with phototherapy and one-dose intravenous injection of human albumin. CONCLUSIONS: It is important to consider and test for the anti-Diegoa antibody in cases of hemolytic disease of the newborn of the Han ethnicities of China.

Retrospective analysis of direct antiglobulin test positivity at tertiary academic hospital over 10 years.

BACKGROUND: Hemolytic disease of the fetus and newborn (HDFN) is a clinically significant problem that may potentially affect any pregnancy. Direct antiglobulin test (DAT) is considered to be an important test in identifying newborns who are suspected to have HDN. This study aims in reviewing data regarding a positive DAT result concerning etiology and the development of HDN over a period of 10 years. STUDY DESIGN AND METHODS: A retrospective study of all neonates with a positive DAT result between January 2011 and December 2020 was performed. Data were obtained from patients' electronic hospital files, transfusion medicine databases, and medical birth records. Laboratory parameters along with clinical interventions in neonates with a DAT-positive result and a comparison group of DAT-negative neonates were performed. RESULTS: 36,000 deliveries were registered in this period. 176 (2.65 %) neonates had a positive DAT result. ABO-incompatibility was the most common cause with 59.1 %; Rh incompatibility 13.8 %, minor blood group incompatibility, and other RBC-related antibodies 10.1 %, and unspecified etiology in 17 % of cases. Among DAT-positive cases, 32.7 % of neonates were diagnosed with HDN. ABO-incompatibility was the major reason as well. Initial mean total bilirubin levels were higher in the DAT-positive group than the control group (p < 0.001), and these neonates also had a lower initial hemoglobin level (p < 0.001). The need for therapeutic interventions was significantly higher in DAT-positive neonates (p < 0.001) as 86.8 % underwent phototherapy, with 32.7 %, and 17.6 % receiving exchange transfusion (ET) and intravenous immunoglobulin (IVIG), respectively. CONCLUSION: In conclusion, ABO incompatibility was the most common cause for neonatal DAT positivity. Besides the common causes of DAT positivity, there would be rare but important conditions that may lead to a positive result, such as antibodies passively acquired from mothers in the context of alloimmunizations or using drugs. In addition, as a high rate of therapeutic intervention was identified among neonates with a DAT-positive result, there is a crucial need for increasing awareness regarding early diagnosis of the condition, careful monitoring, and the employment of prenatal alloimmunization screening tests.

From A to AB: A Caucasian Mother with High Anti-B Titer Causing Hemolytic Disease of the Newborn.

We report on a term infant with clinically significant hemolysis and hyperbilirubinemia. Testing revealed ABO incompatibility between maternal type A and infant type AB. The maternal alloantibody screen was negative. The infant's direct antiglobulin test was positive, and anti-B IgG was eluted off the infant's red blood cells (RBCs). Testing of the mother's plasma revealed a high anti-B titer. The infant was successfully treated with phototherapy and intravenous immunoglobulin. The bilirubin and hematocrit stabilized, and the infant was discharged home. This case was unusual because of its severity and unusual ABO constellation. Furthermore, this report is an exemplary educational case study on how effective collaboration between the clinical team and the blood bank laboratory is critical in reaching the correct diagnosis. In summary, the differential diagnosis of more unusual and atypical ABO-incompatible constellations must be considered when an infant presents with unexplained hemolysis.

Direct antiglobulin test in the prediction of hyperbilirubinemia and predischarge bilirubin levels in infants with mother-infant blood type incompatibility.

BACKGROUND: This research evaluated the association between the mother-infant blood type or rhesus (ABO or Rh) incompatibility, the pattern of neonatal jaundice, and serum bilirubin (TSB) values obtained prior to discharge from hospital of healthy born neonates with gestational age >34 weeks and birth weight >2000 g. METHODS: We utilized a laboratory and neonatal database to identify the cord blood ABO/Rh and direct antiglobulin test (DAT) and TSB measured during hospitalization and re-admission with hyperbilirubinemia for phototherapy treatment. We used hour-specific TSB to analyze the TSB levels for ABO/Rh compatibility and isoimmunization using chi-square, analysis of variance, and regression models. RESULTS: Of the 901 infants studied, 158 (17.5%) had ABO/Rh incompatibility, including 27 with positive DAT. Hyperbilirubinemia was diagnosed in 33.3% DAT positive, 6.9% DAT negative, and 4.6% of infants with compatible blood types. Increased predischarge TSB was observed in DAT positive infants at 48-72 h of postnatal age (P < 0.001). After controlling for age at TSB testing and weight loss percentage, multiple regression analysis did not show any impact of ABO/Rh incompatibility and DAT results on the predischarge TSB levels. CONCLUSION: Blood type incompatibility increases the frequency of hyperbilirubinemia only in the DAT-positive infants. Irrespective of the isoimmunization status, it does not significantly affect the level of predischarge TSB.

Comparison of end-tidal carbon monoxide measurements with direct antiglobulin tests in the management of neonatal hyperbilirubinemia.

OBJECTIVE: Determine whether management of neonatal hyperbilirubinemia differs if one used end-tidal carbon monoxide (CO) corrected for ambient CO (ETCOc) measurements instead of direct antiglobulin test (DAT) results to assess the severity of hemolysis. STUDY DESIGN: Retrospective chart review of infants with total bilirubin and ETCOc levels measured from July 2016 to August 2018. The reported treatment is the hypothetical management infants might have received had there been strict adherence to American Academy of Pediatrics guidelines, rather than the actual management they received. RESULT: Only 27.2% of 191 DAT(+) infants were hemolyzing based on ETCOc, while 29.1% of DAT (-) infants were hemolyzing based on ETCOc. Management of 18 (9.4%) infants differed depending if ETCOc or DAT were used to determine hemolysis. Eight fewer infants would have received phototherapy if ETCOc was used. CONCLUSIONS: ETCOc is a more accurate determinant of hemolysis in the newborn, and its use can lead to less phototherapy.

An Automated Method for Direct Antiglobulin Testing and the Resulting Amount of Phototherapy Used at a Large Academic Medical Center.

OBJECTIVE: To evaluate how clinical practice was affected by the change in direct antiglobulin testing (DAT) methodologies and subsequent stronger reported DAT results at our large academic medical center. METHOD: We retrospectively reviewed DAT results of umbilical cord blood from infants with blood type A or B born to mothers with antibody-negative type O blood, based on records kept at the University of Alabama at Birmingham (UAB) Hospital, a 1400-bed academic medical center. RESULTS: We randomly chose 50 neonates with positive DAT results who had been tested using the tube method and 50 whose testing had used the gel method. Although 86% of results with the tube method were positive microscopically, 52% and 40% of the DAT results with the gel method were 1+ and 2+ positive, respectively. Further, we observed an increase in the number of neonates treated with phototherapy who had been tested using the gel method. CONCLUSION: We report that DATs performed using the gel method had increased DAT strength compared with tube testing, which led to increased use of phototherapy by our clinical colleagues.

Characteristics of Bilirubin According to the Results of the Direct Antiglobulin Test and Its Impact in Hemolytic Disease of the Newborn.

BACKGROUND: Hyperbilirubinemia, which is a sign of hemolytic disease of the newborn (HDN), can irreversibly damage the central nervous system. OBJECTIVES: To determine the etiology of HDN in affected patients and characterize the changing pattern of bilirubin using direct antiglobulin testing (DAT). METHODS: We collected clinical data from newborns who underwent perinatal DAT and from their mothers, between August 2008 and July 2017. RESULTS: Among 303 neonates, 37 (12.2%) showed positive DAT results. The positive predictive values (PPVs) and negative predictive values (NPVs) based on DAT results were 75.7% and 28.9%, respectively, for starting phototherapy. Bilirubin levels increased more rapidly in the DAT-positive group, compared with the DAT-negative group. The initial bilirubin level differed significantly according to the etiology of hyperbilirubinemia. Further, neonates with anti-D showed higher delta bilirubin per day than neonates with other antibodies. CONCLUSION: Our results may help to determine the measurement period for bilirubin according to DAT results and etiology.

Is Cord Blood Bilirubin Level a Reliable Predictor for Developing Significant Hyperbilirubinemia?

OBJECTIVE: We aimed to investigate whether cord blood bilirubin (CBB) level could be used to identify the newborns at a high risk of developing hyperbilirubinemia. STUDY DESIGN: Total and direct serum bilirubin level were evaluated from umbilical cord blood of newborns. We checked blood groups and Rh status of all mothers and determined blood groups and direct Coombs test (DC) of newborns born to mothers whose blood group was O type or Rh negative to determine the maternal-fetal blood group or Rh incompatibility. RESULTS: A total of 418 newborns were included, and phototherapy (PT) was required in 17 newborns. The cutoff value of CBB for predicting the occurrence of significant hyperbilirubinemia requiring PT was 1.67 mg/dL, with a sensitivity of 82% and specificity of 99%. The mean CBB level in babies receiving PT was 2.4 ± 0.9 mg/dL. When blood group, CBB level, DC, gender, and mode of delivery were assigned as possible risk factors, multivariate analysis showed ABO, Rh incompatibility, and CBB level increased the risk of PT requirement. CONCLUSION: CBB could be useful to determine newborns at a risk of developing hyperbilirubinemia and prevent developing severe complications due to delay in diagnosis.

Prevalence of positive direct antiglobulin test and clinical outcomes in Surinamese newborns from D-negative women.

BACKGROUND: In low-resource countries, screening for D antibodies to detect pregnancies at risk for hemolytic disease of the newborn is not routine practice. Retrospective data showed that 5.5% of Surinamese newborns of D-negative women had a positive direct antiglobulin test (DAT), indicating the presence of maternal antibodies against fetal antigens. Here, the frequency and clinical relevance of DAT positivity is evaluated. STUDY DESIGN AND METHODS: Between April 2015 and June 2016, an observational, multicenter cohort study was undertaken among Surinamese newborns born to D-negative women. In newborns, the DAT was performed, and clinical outcomes between DAT-negative and DAT-positive newborns were compared. RESULTS: Of the 232 evaluable newborns, 19 (8.2%) had a positive DAT, of which 11 of 15 antibody-tested newborns had D antibodies. DAT-positive newborns had lower hemoglobin levels (p = 0.02) and a trend toward higher bilirubin concentrations (p = 0.09) in the first days of life compared with DAT-negative newborns. DAT-positive newborns were admitted more frequently (p = 0.02), needed phototherapy treatment almost four times as often as DAT-negative newborns (26% vs. 7%; p = 0.008), and therapy took 2 days longer (p = 0.01). Exchange transfusions were performed in two newborns with D antibodies, both complicated with sepsis. The hospital stay was 2.5 days longer for DAT-positive newborns (p = 0.007). Overall, the prevalence of hemolytic disease of the newborn requiring treatment was 2.2% among the whole cohort of newborns. CONCLUSION: We found a high prevalence of DAT positivity with substantial need for hyperbilirubinemia treatment in newborns in Suriname. These results stress the necessity for better management procedures in D-negative women.

[Positive Coomb's test in newborns; causes and clinical consequences Summary of cases diagnosed in the Blood Bank in the years 2005 to 2012].

INTRODUCTION: Hemolytic disease of the fetus and newborn (HDFN) is caused by the destruction of fetal red blood cells due to red cell antibodies produced by the mother. HDFN can cause fetal hydrops during pregnancy or neonatal jaundice after birth. Direct Antiglobulin Test (DAT) detects antibodies bound to red cells and is a valuable test aiding in the diagnosis of HDFN. In Iceland DAT is routinely performed on cord blood or newborn blood samples if the mother is Rhesus D negative or has non-A/B red cell alloantibodies. The aim of this study was to investigate the causes and consequences of positive DAT in newborns in Iceland over a period of eight years. MATERIAL AND METHODS: The study population was infants diagnosed with a positive DAT in the Blood Bank in Iceland in the years 2005-2012. Relevant data on the blood group and antibody status of mother and child, blood transfusion and DAT results were retrieved from the Blood Bank information system ProSang. Birth records provided information on birth weight, gestational age and phototherapy. Health records from the Children's Hospital provided information on the management and fate of the newborn. RESULTS: Over the study period 383 newborns had a positive DAT result at the Blood Bank. In 73.6% of cases the underlying cause was ABO blood group mismatch between mother and infant, in 20.4% of cases the mother had non-A/B red cell alloantibodies, in 3.9% both of above factors were present, while in 2.1% the cause was unclear. A total of 179 (47.6%) children had neonatal jaundice that required treatment, of which 167 (93.3%) only needed phototherapy. Eight infants required exchange transfusion, five of these had Rhesus antibodies and three ABO blood group mismatch. CONCLUSION: ABO blood group mismatch between mother and child was the most common cause for a positive DAT in neonates in Iceland in the years 2005-2012. Almost half of the neonates required treatment but usually phototherapy was sufficient. Rarely, blood transfusion or exchange transfusion was necessary in severe cases of ABO blood group mismatch or non-A/B red cell alloantibodies. KEY WORDS: Coombs test, Direct Antiglobulin Test (DAT), Hemolytic disease of the fetus and newborn (HDFN), ABO blood group mismatch, red cell alloantibodies, neonatal jaundice, exchange transfusion. Correspondence: Anna Margret Halldorsdottir, annamha@landspitali.is.

Enfermedad hemolítica perinatal causada por anticuerpos anti-M y tratada con inmunoglobulinas intravenosas fetales / Hemolytic disease of the fetus due to anti-M antibodies treated with fetal intravenous immunoglobulin therapy

Presentamos el caso de una mujer de 28 años, con 2 abortos tardíos previos causados por anticuerpos anti-M. En la actual gestación es tratada desde la semana 23 hasta la semana 34 con inmunoglobulinas intravenosas fetales, con resultado satisfactorio. Aunque no hay estudios randomizados y controlados que indiquen que las inmunoglobulinas fetales son efectivas en el manejo de la isoinmunización, pequeñas series de casos sugieren resultados prometedores (AU)

We present the case of a 28-year-old woman with two prior late miscarriages caused by anti-M antibodies, leading to alloimmunization of her previous pregnancies. During this pregnancy, she was successfully treated with intravenous immunoglobulins administered from the 23th to the 34th week of pregnancy. There are no randomized trials to indicate whether the antenatal use of intravenous immunoglobulin is effective in the management of fetal red blood cell alloimmunization. Several case series suggest a beneficial role in preventing severe fetal anemia (AU)

Importance of Direct Antiglobulin Test (DAT) in Cord Blood: Causes of DAT (+) in a Cohort Study.

BACKGROUND: The direct antiglobulin test (DAT) is the cornerstone of the diagnosis of hemolytic disease of the newborn (HDN). The aim of this study was to review the incidence and causes of positive DAT in cord blood in relation to development of HDN. METHODS: We retrospectively reviewed all results of DAT, which is routinely performed in cord blood samples, along with the laboratory and infants' medical records. RESULTS: DAT was positive in 70/2695 (2.59%) cases. In 64/70 (91.43%) cases, DAT positivity was attributed to ABO incompatibility. There were 50/218 (22.93%) DAT (+) cases in the A/O group and 13/97 (13.40%) cases in the B/O group (p = 0.0664). Two DAT (+) cases were attributed to maternal alloimmunization (anti-Fya and anti-JKb, respectively), and one to maternal IgG autoantibodies that developed after methyldopa treatment. Among the 70 DAT (+) cases, 30 (42.86%) cases required phototherapy with no difference between the A/O and B/O groups. The duration of phototherapy in the B/O group was significantly longer than in the A/O group (p = 0.024). There was a trend of correlation of increasing strength of DAT positivity with phototherapy need. No false positive DAT case was detected. CONCLUSIONS: Although ABO incompatibility remains the main reason of DAT (+), other causes (e.g., alloimmunization, drugs) should also be explored. The relevant impact of DAT (+) on HDN development should be considered.

Red Blood Cell Transfusion in Patients With Autoantibodies: Is It Effective and Safe Without Increasing Hemolysis Risk?

BACKGROUND: The therapeutic efficacy of red blood cell (RBC) transfusions in patients with autoimmune hemolytic anemia (AIHA) is highly debated because of speculations on the increased risk of transfusion reactions; yet it is a suggested adjuvant therapy in anemic patients with life-threatening hypoxemia. In this study, we evaluated the safety and efficacy of RBC transfusions in AIHA patients. METHODS: Daily changes in hemoglobin, total bilirubin, and lactate dehydrogenase (LDH) were assessed in 161 AIHA patients without bleeding history who were transfused once with 1-5 units of the least-incompatible RBCs and monitored over a seven-day period. Post-transfusion patients positive for alloantibodies only or those without RBC-specific antibodies were considered as control groups (N=100 for both groups). RESULTS: The three groups revealed similar increases in hemoglobin of 1.40-1.70 g/dL (autoantibodies), 1.20-1.60 g/dL (alloantibodies only), and 1.40-1.55 g/dL (no antibodies) for seven days following transfusion of 10 mL RBCs/kg. During follow-up, no significant changes in total bilirubin or LDH levels were detected in the AIHA group compared with controls. Influences due to autoantibody type, direct antiglobulin test (DAT) specificity and strength, and steroid therapy status on transfusion reactions were not evident in AIHA patients. In addition, changes in hemoglobin levels were significantly higher (P<0.001) in severe anemia (<5 g/dL) than in other patients. CONCLUSIONS: Transfusion of the least-incompatible RBCs in AIHA patients is effective and safe without any associated increase in hemolysis risk when compared with post-transfusion patients positive for alloantibodies or those lacking RBC-specific antibodies.

Maternal anti-D prophylaxis during pregnancy and risk of hemolysis among preterm infants.

OBJECTIVE: To evaluate whether Rh-positive preterm newborn infants born to Rh-negative mothers treated with prophylactic anti-D immunoglobulins exhibited signs of hemolytic reaction, including anemia and hyperbilirubinemia. STUDY DESIGN: Retrospective data were collected for 94 Rh-positive preterm newborns born at gestational age (GA) 28 to 34 weeks to 76 Rh-negative mothers and for matched controls. RESULT: We found 11.7% positive Coombs' tests among infants in the study group and slightly higher bilirubin levels at birth and on the following 3 days. No differences were recorded between the study and the control groups for hematocrit levels throughout hospitalization, maximal bilirubin level, phototherapy treatment or the need for blood transfusion. CONCLUSION: Among preterm Rh-positive newborn infants born to Rh-negative mothers, there appears to be no evidence of significant hemolytic reaction derived from placental anti-D transfer. Further prospective studies are needed to confirm these findings in order to support anti-D administration close to preterm birth.