Abstract
Congenital mesoblastic nephroma is a rare tumor of infancy that usually presents as an asymptomatic abdominal mass. A full-term newborn infant with an atypical variant of this neoplasm developed hemorrhagic shock and disseminated intravascular coagulation. The stormy course was complicated by persistent fetal circulation and then the inability to withdraw ventilatory support due to the mass effect of the tumor. After the removal of the tumor at 10 days of age, transient conjugated hyperbilirubinemia developed. At 15 months of age, the infant was thriving without evidence of recurrence of the tumor.