NOVEL SPINAL DYSPLASIA IN 2 GENERATIONS

We report on a father and son with a previously undescribed skeletal a bnormality and severe short stature. Antenatal sonographic evaluation of the propositus (son), obtained due to maternal pre-eclampsia, sugge sted an abnormal spine. At birth, no congenital anomalies were noted a nd transition to extra-uterine life was smooth. Radiographs performed five days after birth showed spina bifida, hemivertebrae in the midtho racic region, and widened lumbar interpedicular distances. MRI of the lower thoracic and lumbar vertebrae documented crescent-shaped appeara nce of the affected vertebrae and abnormally narrow A-P diameter of th e vertebral bodies. Intervertebral discs were small, and the posterior elements, as well as the spinous processes of the affected vertebrae, were markedly hypoplastic. However, there was no narrowness of the sp inal canal, and the limbs were unaffected. CT scan with three-dimensio nal reformatting of the thoracic and lumbar vertebrae documented unusu al sagittal clefting of all of the vertebral bodies, which has previou sly been undescribed. The father had severe kyphoscoliosis and a heigh t of 131.6 cm (-7.5 S.D.). Radiographically, he was found to have mult iple segmentation anomalies and diminished A-P diameter of his affecte d vertebral bodies. The multiple vertebral anomalies are the probable cause for the father's severe kyphoscoliosis. The pattern of inheritan ce suggests that an autosomal dominant gene is responsible for this co ndition and that the father represents a de novo mutation. These radio graphic abnormalities have not been described previously and represent a new form of vertebral spinal dysplasia. (C) 1995 Wiley-Liss, Inc.