Noonan Syndrome with Massive Fetal Pleural Effusion and Hepatomegaly with Elevated Liver Fibrosis Markers

Abstract

 Noonan syndrome（NS）is a distinctive facial appearance, lymphoid dysplasia, and a congenital anomaly syndrome characterized by heart anomaly. We herein report a female infant in whom right pleural effusion and hepatomegaly were noted at 29 weeks of gestation with bilateral pleural effusion pooling progressively at 30 weeks. She was delivered via Caesarean section at 32 weeks and 2 days of gestation due to a non-reassuring fetal status. She had symptoms specific to NS, such as significant anasarca, distinctive facial features, myeloproliferative disorder（MPD）, and atrial septal defect. In addition, she had also non-specific symptoms, such as hepatomegaly with malformation of the portal vein and elevated liver fibrosis markers. Genetic screening showed a mutation of the PTPN11 gene, which confirmed the diagnosis of NS. Thrombocytopenia, monocytosis and blast cells in the peripheral blood since birth remitted without any treatment and eventually was diagnosed as Noonan syndrome-related myeloproliferative disorder. In cases of fetal pleural effusion and hepatomegaly, chromosomal or genetic abnormalities should be considered as the differential diagnosis. Furthermore, hematologic and liver function including fibrosis markers need to be evaluated to identify any complications such as MPD and liver malformation.