First-trimester features of Fowler syndrome (hydrocephaly-hydranencephaly proliferative vasculopathy)

We describe the features of Fowler syndrome (proliferative vasculopathy and hydrocephaly-hydranencephaly) diagnosed in the first trimester. The pregnancy with no significant family history was referred for karyotyping and ultrasound examination after a cystic hygroma was seen at 12 weeks. At 13 weeks, ultrasound examination revealed hydrocephaly-hydranencephaly, fetal akinesia, and arthrogryposis associated with increased nuchal translucency. The parents opted for termination of pregnancy and the diagnosis of Fowler syndrome was confirmed by pathological examination of the fetus. Calcified necrotic lesions and proliferative vasculopathy were observed in the entire central nervous system including the brainstem and spinal cord. Cases previously reported in siblings suggest an autosomal recessive transmission but specific genetic antenatal diagnosis is not yet available. The diagnosis of proliferative vasculopathy and hydrocephaly-hydranencephaly (Fowler syndrome) should be considered whenever hydrocephaly-hydranencephaly associated with a fetal akinetic sequence are encountered at the end of the first trimester. Genetic counseling is recommended.