Abstract
Binder's or flat facies is one of the consistent features of Chondrodysplasia Punctata (CDP). However, it is yet unclear if isolated flat facies is a distinct entity or they represent a milder form of CDP. We aimed to study the prenatal ultrasound features in all fetuses with flat-facies and its association with CDP. We retrospectively reviewed 62 fetuses with flat-facies in the second/ third trimester for the presence of ultrasound (US) features of CDP. Significant maternal medical history, genetic tests and pregnancy outcomes, where available, were retrieved from hospital records. Forty-one cases had isolated flat-facies, 10 had flat-facies with other structural abnormalities, and 11 had all features of CDP. Epiphyseal stippling was found in all cases of CDP, with the proximal femur being the most common site. The karyotype, chromosomal microarray and clinical exome sequencing data, where available, were reported normal. Maternal systemic lupus erythematosus was positive in one CDP case. About one-third of fetuses with isolated flat-facies and nearly half of the CDP cases chose termination. Although isolated flat-facies may appear as a distinct entity, more post-natal follow-up data is required to ascertain if they are milder forms of CDP. Given the varied genetic and non-genetic causes of CDP, we formulated a diagnostic approach in fetal flat-facies to aid prenatal detection and counseling of CDP.
Keywords
Fetal flat facies - Midfacial hypoplasia - Binders phenotype - Chondrodysplasia punctata - Rhizomelia - Clinical exome sequencing - Chromosomal microarray
