Cleidocranial dysostosis | |
---|---|
Other names | Cleidocranial dysplasia,[1] Marie-Sainton syndrome,[1] mutational dysostosis[2] |
Adult male patient described by Marie and Sainton, 1898 | |
Specialty | Medical genetics |
Symptoms | Missing collarbone, prominent forehead, flat nose, shorter[1] |
Usual onset | Present at birth[3] |
Causes | Genetic (RUNX2 gene)[1] |
Diagnostic method | Based on symptoms and X-rays, confirmed by genetic testing[4] |
Differential diagnosis | Mandibuloacral dysplasia, pyknodysostosis, osteogenesis imperfecta, Hajdu-Cheney syndrome[5] |
Treatment | Supportive care[5] |
Prognosis | Normal life expectancy[3] |
Frequency | One per million people[1] |
Cleidocranial dysostosis (CCD), also called cleidocranial dysplasia, is a birth defect that mostly affects the bones and teeth.[1] The collarbones are typically either poorly developed or absent, which allows the shoulders to be brought close together.[1] The front of the skull often does not close until later, and those affected are often shorter than average.[1] Other symptoms may include a prominent forehead, wide set eyes, abnormal teeth, and a flat nose.[1] Symptoms vary among people; however, intelligence is typically unaffected.[1]
The condition is either inherited or occurs as a new mutation.[1] It is inherited in an autosomal dominant manner.[1] It is due to a defect in the RUNX2 gene which is involved in bone formation.[1] Diagnosis is suspected based on symptoms and X-rays with confirmation by genetic testing.[4] Other conditions that can produce similar symptoms include mandibuloacral dysplasia, pyknodysostosis, osteogenesis imperfecta, and Hajdu-Cheney syndrome.[5]
Treatment includes supportive measures such as a device to protect the skull and dental care.[5] Surgery may be performed to fix certain bone abnormalities.[4] Life expectancy is generally normal.[3]
It affects about one per million people.[1] Males and females are equally commonly affected.[5] Modern descriptions of the condition date to at least 1896.[6] The term is from cleido 'collarbone', cranial from Greek κρανίο 'skull', and dysostosis 'formation of abnormal bone'.[7]