VP31.07: When genetics do not explain the ultrasound: a case report

Abstract

The role of ultrasound (US) during pregnancy is well established. However many diseases and syndromes have manifestations throughout pregnancy and life, but are not always clarified by the US which generate difficulties in counselling. Case report: 27-year-old, 2G0P (1 spontaneous abortion). Normal 1st trimester US, low-risk combined screening but low PAPP-A (0,23MoM). At 20 weeks' US showed female genitalia, an inlet perimembranous ventricular septal defect (VSD), right cardiac cavities disproportion, hyperechogenic foci on the left ventricle, persistence of the right umbilical vein, femur on the 5th centile and umbilical cord with 2 vessels. Uterine mean pulsatility index >95th centile. Fetus with both normal karyotype and array-cGH. Infectious screening was negative. Fetal echocardiogram confirmed previous cardiac findings. At 24 weeks' US, beside cardiac anomalies, long bones were below 5th centile. After genetic counselling (GC) it was decided to do a whole-exome sequence (WES) that was normal. At 28 weeks' US, type 1 fetal growth restriction (FGR) was diagnosed (2,7th centile). Currently she is 32 weeks pregnant, fetus with type 1 FGR (0,3th centile), hypoplasia of long bones, normal fetal flowmetry and abnormal placental flowmetry with cardiopathy (VSD with 4.7mm and disproportion of great vessels with a suspicion of aorta coartation). Antenatal counselling is difficult and the prognosis is uncertain, which must be shared with couple. In conclusion, this case highlights the difficulty in GC. Genetic tests were promptly performed. As the pregnancy was evolving, we came across different malformations-cardiac malformation, placental dysfunction and short long bones. At this point, WES would be important to exclude not only skeletal dysplasia, but also more complex syndromes that could help to explain the various sonographic findings. However, even with adequate GC, it is not always possible to find the explanation to US findings and predict neonatal outcome.