Clinical and Radiological Aspects of Pycnodysostosis: 1st Series of the Genetics Department of the Mohammed VI University Hospital of Marrakech

Abstract

Pycnodysostosis is a rare bone dysplasia with an incidence of 1 in 100,000 cases. It is a genetic disease (from the Greek pycnos = dense, dys = trouble and osteon = bone) also called osteochondrodysplasia, first described in 1962 by Maroteaux and Lamy. It is due to a dysfunction of the osteoclasts, caused by a mutation in the gene that codes for the cathepsin K enzyme. We highlight the role of the geneticist in the early diagnosis and management of pycnodysostosis as well as in the elaboration of an adequate genetic counseling based on a series of 14 clinical cases. Keywords: Pycnodysostosis, Atypical Fracture, Osteoclast, Cathepsin K, Facial Dysmorphia