Sacrococcygeal teratoma with hydrops fetalis and bilateral hydronephrosis.

A 29-year-old Japanese primipara with fetal sacrococcygeal teratoma and hydronephrosis was referred to our department at 22 weeks of gestation. The preload index of the inferior vena cava (PLI) was 0.75 and fetal cardiac failure was suspected at 28 weeks of gestation. The sodium and chloride concentrations and osmolarity of the fetal urine were 96 mEq/L, 81 mEq/L and 204 mOsm/L, respectively, and we predicted a good renal function. Then, a vesico-amniotic shunting operation was performed at 28 weeks of gestation to keep the renal function and PLI decreased 0.41 after this operation. At 30 weeks of gestation, the fetus was delivered by a cesarean section owing to preterm PROM and a huge growing sacrococcygeal teratoma. The baby was female, weighing 2,020 g, and the 1 minute Apgar score was 1. She died almost 7 hours after birth due to respiratory insufficiency. An autopsy confirmed bilateral hydronephrosis, urethral stenosis, sacrococcygeal immature teratoma, and pulmonary hypoplasia. The size of this tumor revealed 80 x 70 x 45 mm in intrapelvic cavity and 130 x 90 x 50 mm out of body, and this tumor was classified as Type II according to the American Academy of Pediatrics Surgery Section classification.