Appropriate surveillance and treatment during pregnancy have led to decreased rates of fetal morbidity and mortality linked to hemolytic disease of the fetus and newborn (HDFN), according to the analysis of a case study published recently in NeoReviews.
The study described a 37-year-old woman who has had five pregnancies. Three of the pregnancies resulted in term births. She experienced no preterm births, two miscarriages and two abortions.
An antibody screenAntibody test A blood test performed during pregnancy to look for antibodies that could affect a developing fetus. performed at her last pregnancy was negative, and at 28 weeks’ gestational age (GA) she was treated with Rhesus (RhRh factor A protein or antigen found on red blood cells. When an Rh-negative mother carries an Rh-positive fetus, her immune system may make antibodies that attack the fetus' red blood cells.) immune globulin. At that time, she gave birth to an Rh-positiveRh-Positive A blood type trait that means your red blood cells have the Rh(D) antigen. baby and received intravenous immunglobulin (IVIGIntravenous immunoglobulin A therapy made from donated antibodies that may help reduce the mother’s immune response and protect the fetus.) following delivery.
Read more about HDFN testing and diagnosis
In the present situation, the patient became pregnant via in vitro fertilization. At 10 weeks’ GA, she exhibited anti-D antibodiesAntibody A protein made by the immune system that recognizes and attacks foreign substances, such as bacteria, or in HDFN, fetal red blood cells carrying incompatible antigens.. Following detection of these antibodies, her husband underwent D-antigen genotyping and was ultimately shown to be heterogeneous for the D antigen.
Based on a 50% risk of the fetus being Rh positive, the mother underwent amniocentesis for assessment of fetal D-antigen genotyping. Findings revealed that the fetus was D-positive as well.
Because the patient was at high risk for early-onset HDFN, at 13 weeks’ GA, she underwent Doppler ultrasonography of the fetal middle cerebral artery peak systolic velocity (MCA-PSVDoppler ultrasound A non-invasive scan that measures blood flow speed in the fetus' brain to diagnose anemia. Specifically, it checks the middle cerebral artery peak systolic velocity (MCA-PSV).), plasmapheresis (plasma exchange) and IVIG treatment.
Treatment with plasmapheresis and transfusion
Initially, the pregnant patient’s MCA-PSV was right below the threshold of 1.5 multiples of the median (MOM), thus offering reassurance that no significant fetal anemiaAnemia A condition that occurs when the body doesn’t have enough healthy red blood cells to carry oxygen to its tissues. In HDFN, anemia occurs when maternal antibodies destroy fetal red blood cells. was present.
After undergoing two plasmapheresis sessions, the patient began to receive weekly IVIG treatments until 26 weeks’ GA. Although her antibodyAntibody A protein made by the immune system that recognizes and attacks foreign substances, such as bacteria, or in HDFN, fetal red blood cells carrying incompatible antigens. titers declined following the plasma exchange and IVIG therapy, her anti-D antibody titers increased once again at 26 weeks’ GA.
At 27 weeks’, two days’ GA, her MSA-PSV was elevated, and the patient was scheduled for fetal blood sampling and a possible transfusion. Findings from the testing were indicative of severe fetal anemia. The fetus received a transfusion; MCA-PSV values declined to near normal after the transfusion.
Repeat PUBS at 29 weeks’, four days’ GA showed an elevation in the MCA-PSV MOM once again. During the PUBS procedure, prolonged fetal bradycardia was detected, which led to the early delivery of a male infant via urgent cesarean section, with no complications.
The baby was hospitalized in the neonatal intensive care unit. He received give packed RBC transfusions and phototherapyPhototherapy A treatment that uses special blue light to help newborns break down bilirubin and prevent kernicterus.. Neither IVIG nor exchange transfusion was required.
The newborn was discharged home at 41 days of age.
“Management of alloimmunizationAlloimmunization When a person’s immune system develops antibodies against foreign antigens from the same species—such as when an Rh-negative mother’s body forms antibodies against her baby’s Rh-positive red blood cells. in pregnant patients should be protocol-driven,” the study author stated. “Current strategies for assessment and therapies allow for more thorough and less invasive management with risks to mother and fetus.”
