Obstetrics and neonatal outcomes of binder phenotype with antenatal diagnosis: A case report and literature review

Background: Binder phenotype (BP) is a term used to define a form of maxillo-nasal dysplasia defined by the presence of flattened nose, verticalized nasal bones, and retrusion of the maxilla (BP triad). This facial anomaly can be associated with other anomalies in both genetic and acquired conditions as well as in isolation. This systematic review aimed to summarize the antenatal findings, maternal and obstetrics characteristics as well as the obstetrics and neonatal outcomes of all cases of BP diagnosed in utero.

Methods: According to the PRISMA statement, we conducted a systematic review of the literatures to identify all the Binder phenotype cases diagnosed antenatally. We extracted and summarized obstetrics and neonatal characteristics of each study, including our case report.

Main findings: We identified a total of 47 cases of BP. The median gestational age at diagnosis was 23 weeks. BP was associated with other skeletal or non-skeletal anomalies in all cases apart from six confirmed to be isolated. Respiratory distress syndrome was observed in 12 neonates and in 18 cases BP was one of the clinical findings of chondrodysplasia punctata X-linked.

Conclusion: BP is often associated with other fetal defects; however, when isolated, BP seems to have good obstetrics and neonatal outcomes. In fetuses with apparent isolated BP at midtrimester, genetic testing with fluorescence in situ hybridization (FISH) for ARSE deletion can be offered for CDPX1 diagnosis while exome sequencing may be more informative in cases where a syndromic condition is suspected. Lastly, BP per se is associated with a higher risk of respiratory distress syndrome and feeding difficulties.