Prenatal Diagnosis of 46,XX,der(13;21 )(q10;q10),+21 and Transient Abnormal Myelopoiesis in a Fetus with Hepatosplenomegaly and Spontaneous Resolution of Fetal Ascites

摘要

A 31-year-old, gravida 2, para 1, woman was referred for genetic counseling at 33 weeks' gestation because of fetal ascites and fetal hepatosplenomegaly detected at 32 weeks' gestation. Level II ultrasound at 33 weeks' gestation revealed a singleton fetus with fetal biometry equivalent to 31 weeks' gestation, fetal ascites and hepatosplenomegaly. Spontaneous resolution of fetal ascites with persistent hepatosplenomegaly was noted at 34 weeks' gestation. Cordocentesis at 34 weeks' gestation revealed a fetal karyotype of 46,XX,der(13;21 )(q10;q10),+21. The maternal karyotype was 45,XX,der(13;21)(q10;q10). The full blood count revealed a marked leukocytosis with a white cell count of 24.69 x 10~3 muL with 30% blast cells and a hemoglobin level of 15.1 g/dL. The blood smear revealed large undifferentiated blast cells with fine granularity of the cytoplasm and large irregular nuclei representing transient abnormal myelopoiesis (TAM). Intrauterine fetal death occurred at 36 weeks' gestation, and a 2,294-g dead female fetus with characteristic features of Down syndrome was delivered. Molecular analysis of the GATA1 gene using fetal tissues revealed that there was no mutation in the GATA1 gene.