P12.12: Skeletal dysplasias: is it possible the diagnosis before the delivery?

Abstract

Objectives: The osteochondrodysplasias, or skeletal dysplasias are a genetically heterogeneous group. In the 2006 revision of the International Nosology and Classification of Genetic Skeletal Disorders, 372 different conditions were listed in 37 groups defined by such molecular, biochemical, and/or radiographic criteria. Many of them can present in the prenatal period as demonstrated by ultrasound. We report the prenatal diagnosis of skeletal dysplasias in three centers over 5 years period. Methods: Over 21,000 scans in three centers of prenatal diagnosis were made for suspect of skeletal displasya or routinary scan during 2004–08 period. In the most of cases the invasive prenatal diagnosis (chorionic villus sampling/amniocentesis) was performed and the final diagnosis was sought on the basis of fetopathological examination, radiographic studies and molecular testing. Results: A total of 70 antenatal skeletal dysplasias were diagnosed. Follow-up was in all cases, also if the parents decided to stop the pregnancy. The mean gestational age at US diagnosis was 24 wks (12–35 wks). The lethal skeletal dysplasias were diagnosed in the second trimester, instead the diagnosis of limb reduction was possible in the first trimester. Were diagnosed 31 cases of skeletal dysplasia (44,2%), 24 cases of limb reduction (34,2%), arthrogryposis 5 cases (7,1%), amniotic band lesion 5 cases, unexplained skeletal 5 cases (without diagnosis), dysplasia/limb defect 5 cases. A correct antenatal diagnosis was made in 55 cases (78,5%). Conclusion: A specific prenatal diagnosis is not possible in 20/30% of the cases. The diagnosis on the basis of specific pathology is made in a large period of the pregnancy (12–35wks). For an immediate management, assessment of prognosis (95%) is of more value by US plus molecular diagnosis. The definitive diagnosis is made postnatally based on clinical, radiographic, CT criteria and molecular analysis.