Management of isoimmunization in the presence of multiple maternal antibodies

OBJECTIVE: Evaluation and management of patients with multiple maternal antibody isoimmunization is unclear. The presence of ≥ 1 maternal antibody may suggest a worse scenario. The objective of this study was 2-fold: first, to determine whether the presence of multiple antibodies predicts a more severe course than single antibodies and second, to determine the utility of the Queenan curves/protocol in evaluating multiple-ani-body isoimmunization. STUDY DESIGN: Amniotic fluid ΔOD⁴⁵⁰ measurements were obtained from the antenatal testing logbook and confirmed by chart review. Cases were categorized by antibody type and clinical outcomes obtained by chart review. RESULTS: Twenty-four pregnancies with isoimmunization and multiple maternal antibodies were identified; of these, 17 had 2 antibodies (anti-D and -C in 13; anti-D and -E in 1; anti-D and -Jka in 1; anti-c and -E in 1; and anti-c and -Jka in 1), and 7 had > 2 antibodies (anti-D, -C, and -E in 4; anti-D, -C, and -N in 1; anti-c, -E, and -FYA in 1; and anti-E, -K, -Fya, -S, and -C in 1). Eleven patients (46%) required at least 1 intrauterine fetal transfusion (mean initial fetal hematocrit, 15%; range, 4.9%-24%). In those not transfused, no ΔOD⁴⁵⁰ measurements occurred in the Queenan "fetal death risk" zone. Poorest outcomes (multiple transfusions/ hydrops/fetal demise) were in patients with anti-D and anti-C, with or without anti-E. The absence of anti-D was associated with no need for fetal transfusions. The overall transfusion rate was significantly higher compared with a group of 57 isoimmunization patients with only anti-D (46% vs 25%, P≤ .05). CONCLUSIONS: The presence of anti-D appears to be the most significant factor guiding the course of isoimmunization with multiple antibodies. The presence of another antibody with anti-D appears to significantly increase the need for intrauterine fetal transfusions. The Queenan protocol can successfully treat patients with multiple maternal red blood cell antibodies.