Maternal ABO-mismatched blood for intrauterine transfusion of severe hemolytic disease of the newborn due to anti-Rh17.

BACKGROUND: Clinically significant antibodies to high-incident antigens present a challenge in hemolytic disease of the newborn. Antigen-negative blood may be difficult to obtain for intrauterine transfusion (IUT). In these instances, maternal blood is de facto compatible regardless of an ABO mismatch. CASE REPORT: A group B/D-- woman with a history of hemolytic disease of the newborn due to anti-Rh17 (titer 256) presented to the obstetrical clinic at 12 weeks gestation for management of her third pregnancy. She consented to donate blood for possible IUT. STUDY DESIGN AND METHODS: Washed maternal packed cells were suspended in saline to 75 percent Hct and irradiated before transfusion. The fetus was transfused via the intrahepatic vein. RESULTS: Ultrasound examination at 19 weeks indicated a hydropic fetus. The fetal blood group was O Rh+, direct antiglobulin test 4+, and hemoglobin 22 g per L. A total of 368 mL of maternal blood was transfused during seven procedures. Labor was induced at 38 weeks, and a 2560-g male infant was delivered by Caesarian-section due to fetal distress. The infant grouped as B Rh+, direct antiglobulin test negative. No group O red blood cells were detected. The hemoglobin level was 143 g per L rising to 209 g per L at discharge 3 days later. The indirect bilirubin was 55 micromol/L and remained stable during the hospital stay. Phototherapy was discontinued after 1 day, and the infant was discharged without an exchange or top-up transfusion. CONCLUSIONS: Maternal ABO-mismatched blood is an alternate source for IUT in instances when antigen-compatible allogenic blood is unavailable.

The serum transferrin receptor concentration in seven fetuses with hemolytic disease.

Six pregnant women who received intrauterine transfusions and their seven fetuses were followed during gestation. Hemoglobin concentration, hematocrit value, serum ferritin, and serum transferrin receptor (TfR) concentrations were measured. In the fetal samples, there was a tendency for the TfR concentration to decrease during gestation and after the intrauterine transfusions. Serum TfR values varied between 0.7 and 5.2 mg/L, which is near the postnatal level measured in premature infants. On the contrary, one would have expected to find highly elevated values due to the active fetal erythropoiesis. The fetal regulation of TfR production may differ from that described postnatally.

Ultrasonographic fetal cardiac measurement in isoimmunized pregnancies.

OBJECTIVE: To investigate the predictive value of the ultrasonographically measured fetal biventricular outer dimension (BVOD) in diastole in detecting neonatal anemia in pregnancies complicated by isoimmunization. STUDY DESIGN: The records of all patients evaluated for isoimmunization in pregnancy from January 1992 to December 1994 were reviewed retrospectively. The fetal BVOD had been measured with real-time-directed M-mode fetal echocardiography. The BVOD measurement was plotted on a nomogram (with reference to biparietal diameter) and a percentile value determined graphically from the nomogram. Neonatal outcome was obtained prospectively and by chart review. RESULTS: Sixty-three singleton fetuses from the study period who met entry criteria were identified. Anti-D sensitization represented 66% of cases of isoimmunization. Twenty (32%) fetuses required subsequent neonatal transfusion, and 43 (68%) did not. Seventeen fetuses (27%) had BVOD measurements greater than the 95th percentile, and 10 (59%) required subsequent transfusion. Infants in this group also had significantly lower hematocrits at birth (37.7 +/- 13.0% vs. 46.6 +/- 9.0%) and prolonged neonatal intensive care unit stay (10.7 +/- 10.0 vs. 4.7 +/- 3.6 days), respectively, when compared to patients with a BVOD measurement less than the 95th percentile. A BVOD 95th percentile threshold had a sensitivity, specificity and positive predictive value of 50%, 84% and 59%, respectively, in predicting the need for neonatal transfusion. CONCLUSION: In patients with isoimmunization, a BVOD measurement in the 95th percentile or greater was associated with a relatively high likelihood of neonatal anemia and transfusion. Although the measurement is not sufficiently sensitive to be used as a single parameter in predicting neonatal compromise in these patients, it can be a useful, noninvasive adjunct to the management of isoimmunized pregnancies.

Prenatal determination of genotypes Kell and Cellano in at-risk pregnancies.

OBJECTIVE: To evaluate the accuracy of a DNA-based testing methodology in determining the KEL1 and KEL2 (Kell and Cellano) genotype of fetuses at risk for Kell or Cellano hemolytic disease. STUDY DESIGN: DNA was extracted from chorionic villus samples (CVS) or amniotic fluid (AF) cells, a portion of the Kell gene was amplified, the amplified product was cut with a restriction enzyme that recognizes the KEL1 nucleotide substitution, and the digested product was run on a polyacrylamide gel to separate the fragments. This analysis was routinely run on uncultured cells to provide rapid results. Testing of parental DNA was performed in conjunction with fetal analysis to ensure that their alleles were detectable with this DNA test. RESULTS: We determined the fetal KEL1 and KEL2 genotype in 1 CVS and 65 AF specimens. Forty-eight of them were determined to be KEL2, 17 were KEL1/2, and 1 was KEL1. Among the fetuses born to date, follow-up information was available on 14 of them, 11 KEL2 and 3 KEL1/2. In all 14 there was complete correlation between the DNA analysis and the serotype or clinical course. CONCLUSION: Determination of the fetal KEL1 and KEL2 genotype using this DNA-based method provides accurate and timely information that can aid the prenatal care of women sensitized to these Kell antigens.

The expression of IgG Fc receptors on circulating leucocytes in the fetus and new-born.

The expression of Fc-gamma-R (FcR) classes on circulating leucocyte lineages (lymphocytes, monocytes, granulocytes) was determined by flow cytometry in 46 fetuses at 18-35 weeks of gestation and in 11 full-term neonates, and compared to that in 20 adults. Classes of FcR present on adult leucocytes could be detected on the corresponding fetal cells as early as 18 weeks of pregnancy. Generally, in the fetus, FcR expression was lower than in the adult while in the neonate it approached values found later in life. However, percentages of Fc-gamma-RIII-positive fetal/new-born monocytes, and those of FcR-positive new-born granulocytes were considerably raised above adult levels. The modified pattern of FcR expression on fetal/new-born leucocytes is likely to influence their IgG-mediated effector activities towards targets such as red cells and platelets.

Fetoplacental blood volume estimation in pregnancies with Rh alloimmunization.

Direct intravascular fetal transfusion under ultrasound guidance has become an important method of treating fetal anemia secondary to maternal red cell alloimmunization. An estimate of normal circulating volume would be useful in selecting the volume of donor blood to be transfused to achieve a desired final hematocrit. Thirty-five fetuses between 21 and 35 weeks of gestation underwent 67 direct intravascular transfusions. The fetoplacental volume relative to fetal weight estimated by ultrasound was found to be relatively constant throughout gestation at approximately 100 cm3/kg. The severity of fetal hemolytic disease and its treatment with intrauterine transfusions did not appear to alter the fetoplacental volume. A nomogram for fetoplacental blood volume versus gestational age is described.

Fetal hyperinsulinism in rhesus isoimmunization.

Analyses of peritoneal ascitic fluid obtained prior to intrauterine transfusion show that some babies with severe rhesus isoimmunization develop raised insulin levels up to a month before delivery. The glucose content of fetal ascitic fluid is usually only about 10 mg. per 100 ml. less than the glucose content of maternal plasma and there is no evidence that this relation is influenced by the fetal or maternal insulin level. The electrolyte content of fetal ascitic fluid is very similar to that of maternal plasma, but fluid from babies with hyperinsulinism has an unusually high calcium content.