The comprehensive assessment of blood typing is essential for the early diagnosis of and timely intervention in hemolytic disease of the fetus and newborn (HDFN), according to findings from a case report recently published in Clinical Pediatrics.
Study researchers stated that screening of pregnant women, especially in situations in which alloimmunization exists, should include searching for the presence of any subgroup incompatibilities. The use of such a proactive strategy is critical for enhanced prediction, early diagnosis, and timely intervention of the approaches needed for prevention of neonatal anemia and hyperbilirubinemia.
An unusual case of HDFN
The current case analysis elucidates the complex, multifaceted nature of HDFN, they stated. The researchers sought to highlight that in the scope of Rhesus (Rh)-negative pregnancies, the subtle presence of minor blood group disparities should not be disregarded, particularly when a strongly positive indirect Coombs test (ICT) is reported in spite of the use of prior anti-D prophylaxis.
The investigators described a female infant born prematurely at 32 plus six weeks’ gestational age (GA) at Surya Hospitals, Mumbai, India. The 1.945-gram baby was born to a 29-year-old second-gravida mother. The blood group of the mother was O Rh-negative, and she had been sensitized to the RhD antigen in a previous pregnancy, in which the baby she delivered was blood type O Rh-positive. In her current pregnancy, the ICT exhibited titers of 1:256 at 24 weeks’ GA and 1:512 at 32 weeks’ GA. The baby was subsequently delivered by emergency lower-segment cesarean section and immediately transferred to the neonatal intensive care unit.
Read more about the prognosis of HDFN
The newborn’s blood type was O Rh-positive. Results of a direct antiglobulin test demonstrated a strong 4+ reaction. The infant’s cord blood bilirubin level was 3.9 mg/dL; hemolysis and an elevated reticulocyte count were reported as well. The mother’s red blood cell (RBC) phenotype was “cceekk,” whereas the infant’s RBC phenotype was “Cceekk.” An HDFN diagnosis was rendered based on the concomitant RhD incompatibility and C-antigen incompatibility.
Treatment and stabilization
The baby received intensive phototherapy at the onset of hyperbilirubinemia. Anemia developed on day eight which resulted in the infant undergoing a transfusion of packed RBCs (PRBCs) using O Rh-negative blood. Also on day eight, phototherapy was discontinued because the newborn’s serum bilirubin concentration was then below the threshold that necessitated treatment. Ultimately, the infant was discharged home on day 10.
Additionally, in the fourth week of life, the baby required a transfusion of PRBCs because of anemia. At 10 weeks of age, her hemoglobin and hematocrit levels stabilized. She showed normal linear growth and development at her follow-up visit.
“This case presents an exceptional instance of [HDFN, in which] RBC hemolysis resulted from the coexistence of Rh-D and anti-C antibodies,” the authors wrote. HDFN provides an “intricate tapestry of maternal alloimmunization against fetal erythrocyte antigens, leading to the hemolysis of RBCs.”
Maternal sensitization in a previous pregnancy led to the emergence of both Rh-D and Rh-C antibodies in the newborn’s circulation. In fact, an elution test was carried out to verify the dual immunization, which provided indisputable evidence of the coincidence of both anti-D and anti-C antibodies.
Although preventive strategies such as “the administration of anti-D immunoglobulin have substantially reduced the incidence of Rh-D isoimmunization, the simultaneous coexistence of multiple minor blood group antibodies leading to [HDFN] remains an exceptional occurrence,” the authors concluded.
