Pycnodysostosis: Clinical and Radiological Features in Two New Egyptian Families

Abstract

Background and Aims: Pycnodysostosis is a rare hereditary disorder, first described in 1962 by Maroteaux and Lamy. It is an autosomal recessive osteochondrodysplasia, characterized by short stature, osteosclerosis, acro-osteolysis, frequent fractures and skull deformities. Less than 200 patients have been reported worldwide since the first description of the phenotype in 1962, out of which only a few cases were reported from Egypt. The purpose of the article was to review the clinical and radiographic characteristics of pycnodysostosis based on some new Egyptian cases. Case Report: We present two Egyptian families with cases presenting very early in life. The patients showed distinctive clinical features and, in spite of the lack of history of frequent bone fractures, they were investigated through complete skeletal survey and CT skull. The detection of dense bones and certain characteristic radiological findings finally led to the diagnosis of pycnodysostosis. The article also reports some unusual findings including conductive hearing loss, radiological findings akin to Erlenmeyer-flask deformity and lack of marked bone fragility. Conclusion: We report here three pediatric cases affected with pycnodysostosis belonging to two Egyptian families. We describe the clinical findings, radiographic features and differential diagnosis of the studied cases. Our study strengthens the role of the radiological examination in reaching the definite diagnosis of pycnodysostosis.

Keywords

• pycnodysostosis

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