Lethal syndrome of skeletal dysplasia and progressive central nervous system degeneration.

We describe 3 sibs (2 males and 1 female) with multiple congenital anomalies, poor growth, seizures, and progressive central nervous system (CNS) degeneration leading to death in infancy. Radiographic changes in all 3 were similar, and included moderate shortness of long bones, platyspondyly, and hypoplastic pelvis. Autopsies showed diffuse encephalomyelopathy and enlargement of the lateral and third ventricles. Lysosomal enzyme activities were normal. Collagen type II analysis on 2 of the sibs indicated normal collagen. Chromosomes appeared normal. Even though the radiographic and chondroosseous morphologic findings in these sibs have a certain similarity to Dyggve-Melchior-Clausen syndrome, their clinical course does not fit this condition. These infants appear to represent a new syndrome of bone dysplasia and CNS degeneration inherited as an autosomal recessive trait.