A 1780-g white male neonate with severe fetal hydrops was delivered vaginally to a 38-year-old, blood type O positive, primigravida mother after 26 weeks of gestation. Prior to the onset of preterm labor, the pregnancy had been uncomplicated. Prenatal care included a sonogram and amniocentesis at 15 weeks of gestation that revealed a fetal size consistent with dates and a 46, XY karyotype, respectively.
At birth, the infant was cyanotic with poor muscle tone and no respiratory effort. There was anasarca but no other obvious deformity. Resuscitation included tracheal intubation, bilateral chest tube placement, inotropic support, and vascular volume expansion. Apgar scores were 1 at 1 and 5 minutes (heart rate only), and 2 at 10 minutes (heart rate only).
Initial laboratory values included a hematocrit value of 0.60 and a white blood cell count of 12.1×109/L, with 12 neutrophils, 14 bands, and 3 metamyelocytes. The absolute neutrophil