TRISOMY-21, FETAL HYDROPS, AND ANEMIA - PRENATAL-DIAGNOSIS OF TRANSIENT MYELOPROLIFERATIVE DISORDER

Background: Aneuploidy is frequently cited as an etiology of hydrops f etalis. Traditionally, associated anomalies (specifically cardiovascul ar abnormalities) have been postulated as the causative factor. Cases: We report two cases of severe anemia associated with hydrops in fetus es that later proved to have Down syndrome. The hematocrit in both fet uses was markedly decreased. The white blood cell count was normal in one but greatly elevated in the other; the latter infant had thrombocy topenia. These findings are consistent with transient myeloproliferati ve disorder. Conclusions: Nonimmune fetal hydrops and trisomy 21 may b e associated without cardiac or anatomical anomalies. Transient myelop roliferative disorder has been seen in neonates with trisomy 21 and ma y be a cause of hydrops in some aneuploid fetuses. Chromosomal analysi s should not be excluded in the workup of nonimmune hydrops when anemi a is found, and therapy may be withheld until karyotyping has been per formed.