Case report
This is a case of a 30-year-old woman, G5P2, with non-contributive family and personal history who was referred to our department at 15 weeks of gestation because of the shortening of all long fetal bones.
Her first previous pregnancy was uncomplicated with normal outcome. The follow-up pregnancy resulted in pregnancy termination due to a lethal skeletal dysplasia diagnosed at 24 weeks of gestation. The final diagnosis of this affected fetus was short rib-polydactyly syndrome type 3 (Verma-Naumoff).
The shortening of the long bones was discovered during the first trimester ultrasound scan at 12 weeks of gestation (NT=1 mm, CRL= 58 mm). Our ultrasound exam at 15 weeks of gestation showed bilateral rhizomelic shortening of the bones without any signs of fractures.
The superior extremities showed a physiological movement of the fingers. The spine did not seem to be hypocalcified. The chest was narrow with short ribs. The rest of the exam did not reveal any additional findings.
Our differential diagnosis based on the ultrasound findings and the history of the patient included short-rib polydactyly syndrome. The patient decided for the termination of the pregnancy due to an adverse prognosis for the fetus. The karyotype was normal and FGFR3 mutation was negative.
The pathology examination confirmed our ultrasound findings: polydactyly of the feet, rhizomelic shortening of the long bone and short ribs. The final diagnosis was short-rib polydactyly syndrome type 3.
Images 1,2: Image 1 shows the femur and tibia which were both markedly shortened. Image 2 shows a 3D image of the arm.