VARIABLE PRENATAL PRESENTATION OF PFEIFFER SYNDROME: SUGGESTED AIDS TO PRENATAL SONOGRAPHIC DIAGNOSIS.

BackgroundOur purpose was to describe and compare the cranial and extracranial abnormalities of Pfeiffer syndrome on prenatal imaging with postnatal or postmortem findings, which may help in prenatal diagnosis of Pfeiffer syndrome (PS). MethodsCases of fetuses with a confirmed diagnosis of PS over a 4-year period (2012-2016) were retrospectively reviewed. Prenatal imaging findings, postnatal, or postmortem investigations and genetic test results were analyzed. ResultsFour fetuses were ascertained, 3 with prenatal sonographic findings compatible with PS and one only diagnosed at postmortem. Cases were referred between 22 and 24weeks' gestation. Three of the 4 cases were terminated, and details of postmortem/postnatal examination were available in all. There was variable presentation of features. Craniosynostosis was present in 3 cases, but only detected prenatally in 2. Extracranial signs included abnormalities of thumbs and/or big toes, detected prenatally in 3 of the 4 cases. A sacral appendage and vertebral or coronal clefts were present at postmortem in 3 cases but only detected prenatally in one. A cartilaginous tracheal sleeve was detected at postmortem in all 3 cases but not detected by prenatal ultrasound. Other findings included ventriculomegaly, posterior fossa, and facial anomalies. Molecular testing revealed mutations of the fibroblast growth factor receptor 2 (FGFR2) gene in all cases. ConclusionPfeiffer syndrome has a highly variable phenotype, and the absence of craniosynostosis on prenatal US does not exclude the diagnosis. Presence of abnormal thumbs and big toes, a sacral appendage, vertebral fusions, and coronal clefts should lead to prenatal molecular testing for PS.