The use of intrauterine transfusions (IUTs) is instrumental in treating severe fetal anemia associated with hemolytic disease of the fetus and newborn (HDFN), according to findings from a case study presented at the 21st World Congress in Fetal Medicine, held between June 23 and June 27, 2024, in Lisbon, Portugal.
When HDFN occurs, maternal alloantibodies of the immunoglobulin G class cross the placenta, where they can mount a response against fetal red blood cell (RBC) antigens. This immune response can cause hemolysis, in which the fetal RBCs are destroyed, which can lead to fetal anemia.
The current report depicts a case of severe, early fetal anemia due to alloimmunization by antibodies to the Rhesus (Rh) D, C, E and Kell antibodies. The patient was a 31-year-old woman with blood type A Rh-negative. She had undergone a previous cesarean delivery, in which no complications were reported and she received postpartum anti-D immunoglobulin (RhIg), as well as a prior miscarriage, at which time she did not receive RhIg.
At 20 weeks’ gestational age (GA), the patient was referred to the Fetal Medicine Department of an institution located in a metropolitan city in southern Brazil. Her referral was based on the results of an indirect Coombs test of 1:2048. An RBC panel revealed fetal anti-D, C and E antibodies, with Kell antibodies not discounted.
Read more about the prognosis of HDFN
Although no fetal abnormalities were observed on her initial ultrasound, results of middle cerebral artery-peak systolic velocity (MCA-PSV) were at the upper limit of normal. A follow-up examination of the patient showed an MCA-PSV of 2.5 MoM, which suggested the presence of severe anemia.
Based on results of cordocentesis, the development of ascites and a hemoglobin level of 4.6 g/dL, the patient received her first IUT, which was subsequently followed by five additional IUTs. The last IUT was performed at 32 weeks, one day gestational age (GA).
Immediately following the sixth IUT, the patient underwent a cesarean section, which led to the delivery of a male newborn who weighed approximately 4.9 lbs. The baby was admitted to the neonatal intensive care unit to undergo monitoring.
The newborn subsequently underwent two RBC transfusions for severe anemia and two platelet transfusions for thrombocytopenia, along with intensive phototherapy. Ultimately, the baby was discharged from the hospital at 21 days after birth, following the resolution of all cytopenias.
The risk for HDFN, which rises with the severity of anemia, is more common among hydropic fetuses. All pregnant women who are RhD-negative need to undergo antibody screening at their first prenatal visit for each of their pregnancies. It is recognized that the indirect Coombs test is the most often used approach to establish a patient’s antibody titer, with the diagnosis of alloimmunization rendered via detection of anti-D antibodies in maternal blood.
“. . . IUT is an effective therapeutic procedure indicated for cases of severe fetal anemia, especially between 18 and 35 weeks [GA],” the authors stated. “If not diagnosed and treated, alloimmunization can cause significant perinatal morbidity and mortality.”
