Hydrops Fetalis and Mirror Syndrome Secondary to Rh-D Alloimmunization, Associated with Oligohydramnious: A Case Report

One of the most common causes of fetal anemia is red cell alloimmunization. The most common routes of maternal sensitization are via blood transfusion or fetomaternal hemorrhage. Antibodies can cross the placenta during pregnancies in alloimmunized women and, if the fetus is positive for these specific erythrocyte surface antigens, result in hemolysis of fetal erythrocytes and anemia. This in turn, can lead to potentially disastrous consequence for the fetus, such as Hydrops Fetalis (HF), a high-output cardiac failure syndrome. The standard treatment in fetuses with anemia is intrauterine transfusion (IUT). Mirror Syndrome (MS) is a rare condition in pregnancy, in which maternal edema in pregnancy is seen in association with severe fetal and/or placental hydrops. The pathogenesis, although not well established, mimics trophoblastic damage and maternal vascular endothelial dysfunction, as is also observed in preeclampsia, and hence, the two conditions may have a similar clinical presentation [1]. The clinical manifestations of this disease are complex. It is easily underdiagnosed and timely intervention is needed to prevent fetal and maternal morbidity. MS can be reversible when the underlying factors are identified and modified [2, 3]. If correction of the underlying fetal abnormality is not possible, the consensual treatment is to deliver the hydropic fetus and placenta, with improvement of the maternal condition shortly thereafter. We report a case of HF and MS secondary to Rh-D alloimmunization that did not respond to IUT.