A female singleton is delivered at 30 6/7 weeks’ gestational age via cesarean for preterm labor and breech presentation. The mother is a 37-year-old grand multipara in her 10th pregnancy. The pregnancy is notable for severe fetal anemia, high-output cardiac failure with normal cardiac anatomy, polyhydramnios, and a placental chorioangioma diagnosed at 26 weeks of gestation. Evaluation for congenital infections is negative. At 25 and 28 weeks’ gestation, the fetus had received in utero red blood cell transfusions for severe fetal anemia. At birth, the infant has respiratory depression requiring intubation and ventilation. Apgar scores are 7, 6, and 8 at 1, 5, and 10 minutes, respectively, and her birthweight is 1,416 g. The neonate is noted to have a protuberant abdomen with significant hepatosplenomegaly, diffuse subcutaneous edema, petechiae, and ecchymoses. The infant requires significant ventilator support for the first few weeks after birth. Chest radiography shows no evidence of pleural or pericardial effusion. Echocardiography shows normal cardiac segmental anatomy with significant biventricular hypertrophy, though blood pressure is maintained. Significant anemia, thrombocytopenia, and coagulopathy are noted over the first days after birth, for which the newborn requires multiple blood products. Profound jaundice necessitates multiple double-volume exchange transfusions. Thrombocytopenia and coagulopathy gradually improve over the first week after birth. However, the infant develops significant cholestasis, reaching a peak direct bilirubin of 12.5 mg/dL (213.8 μmol/L) at 2 weeks of age. The unique constellation of findings in this case, anemia, thrombocytopenia, high-output failure, and cholestasis, presented a broad differential diagnosis. The differential included congenital heart disease and vascular malformations, infectious etiologies, metabolic and genetic disorders, and various renal, hepatic, gastrointestinal, and hematologic pathologies. Sepsis evaluation was performed on admission and …