Generalized skeletal dysplasia resulting in defects in
the development of skull, clavicles, pelvis, and teeth.
Cleidocranial Dysostosis; Scheuthauer-Marie-Sainton Syndrome;
More than 500 cases have been reported worldwide. No
Autosomal dominant. There is a wide variability in
The disorder is caused by mutations in the
transcription factor CBFA1 of the runt domain gene family. The responsible
gene has been mapped to 6p21. This situation results in generalized
dysplasia of bone and dental tissue. Initially it was postulated that the
disease affects only the membranous bones (neurocranium, a portion of the
clavicle, and some facial bones). However, we now know that cleidocranial
dysplasia is a generalized skeletal dysplasia. There is growth retardation
and a slight effect on skeletal maturation over time.
Based on the clinical findings of skull, dental, pelvic,
and clavicular malformations and confirmed with genetic mapping. Radiographs show
persistently open skull sutures and fontanelle with bulging of the calvarium,
short fifth finger middle phalanx, and characteristic bone changes.
The disease involves mainly the head and neck
(brachycephaly, enlarged calvaria, frontal bossing with wide forehead and
hypertelorism, wormian bones, large foramen magnum, hypoplasia or absence of
frontal and paranasal sinuses, midfacial hypoplasia, micrognathia, nonunion
of mandibular symphysis, high arched palate or cleft palate, delayed
eruption of deciduous and permanent teeth, enamel and root hypoplasia,
cavities, supernumerary teeth [up to 30 extra teeth have been described],
and deafness) and the skeleton (short stature, spina bifida occulta,
[unilateral or bilateral] hypoplastic [more often at the acromial than at
the sternal end] or aplastic [rare] clavicles with the ability to appose the
shoulders, narrow, bell-shaped thorax with short, oblique ribs, cervical
ribs, small scapula with dysplastic acromial facets and supraspinatus
fossae, hypoplastic pubic bones with widened symphysis pubis, hip
dislocation, generalized joint laxity, brachydactyly, excessive length of
metacarpal and metatarsal II (and V) bones secondary to extra
epiphyses, short middle phalanx of the fifth fingers, cup-shaped and
hypoplastic distal phalanges with onychodysplasia). Respiratory distress
Because of the facial malformations
and the abnormal and fragile teeth, the airway must be examined closely with
regard to difficult management. Assessment of respiratory function (clinical
examination, chest radiographs and/or computed tomography scanning,
pulmonary function tests, arterial blood gas analysis) is required secondary
to the usually narrow thorax, which results in decreased compliance and
respiratory distress in early infancy. Cor pulmonale has not been described in this condition,
but the potential for increased right ventricular pressure should be kept in mind.
Patients may have difficult airway
management and be at risk for postoperative respiratory distress in the
presence of reduced pulmonary reserves. Maintain spontaneous ventilation
until the airway has been secured. Care with positioning is essential
because of joint laxity and the tendency for dislocations. Keep spinal and
vertebral anomalies in mind if considering central neuraxial blockade.
Abnormal clavicles may make central venous access difficult ...