Review Article
Nadia Ben Jamaa, Achour Radhou
Abstract
Objective: Dyssegmental dysplasia, Silverman-Handmaker Type, is an autosomal recessive lethal disorder, originally considered as a Kniest-like skeletal dysplasia with camptomelia. It is linked to functional null mutations of the perlecan gene (HSPG2) located on chromosome 36.1-35. We report the first case diagnosed in our department. Study: A 31 year-old mother, prim pare and non-consanguineous with her husband, given a 15-16 weeks-aged foetus with dwarfism and dyssegmental dysplasia detected prenatally by ultrasonography. A medical termination of the pregnancy was indicated. Radiographs and autopsy were performed. External examination showed a facial dysmorphy, thick neck, pterygia and micromelia with curved limbs, chest narrowing and an abducted hallux in the right foot. No anomaly in visceral examination was found. The radiographs showed short limbs with Kniest like large metaphyses, bowing of long bones and pleomorphic vertebral bodies with irregular segmentation and absent ossification of pelvic bones. The cranial vault was normal. Histologically, the resting cartilage showed scattered, large puddle-like spaces. The physeal growth zones were disorganized. Conclusion: Prenatal diagnosis is useful to detect this type of skeletal anomaly in order to indicate medical termination of the pregnancy earlier. Fetopathological examination and skeletal radiographs are mandatory in order to establish a precise diagnosis allowing a suitable genetic counselling.