Cleidocranial dysplasia is a genetically inherited medical condition that is also known as Cleidocranial Dysostosis, Marie- Sainton Disease, or Osteodental Dysplasia.
Cleidocranial dysplasia is a rare disorder that affects the skeletal system. The development of the bones and the teeth are affected, although the degree to which they are affected is markedly different in each patient.
The symptoms of this condition can be mild enough to escape detection and diagnosis in some newborn babies. Moreover, cleidocranial dysplasia may be seen in early childhood in some children and may not show up as a hindrance at all for some adults.
On the other hand, some babies may have such severe symptoms that the diagnosis can be made at birth, simply through clinical observation of the abnormal bone development.
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Symptoms
The clavicles of patients with Cleidocranial dysplasia may be partially formed or even missing altogether. This can cause the shoulders of the baby to be brought right up together in the front of the body due to this skeletal abnormality.
The ossification of the fontanelles is also delayed in cleidocranial dysplasia patients. As a result, the space between the skull bones remains open for a longer time than usual, leaving the child vulnerable to head injuries.
The mandible, or jaw bone, and the frontal bossing, or the brow bone, may both have a prominent protruding angle in patients with this condition as well. Cleidocranial dysplasia patients also often have a wide nasal bridge due to increases in the space between the eyes due to hypertelorism. The child may also suffer from vision issues.
There is a possibility of a high arched palate or even a cleft palate or cleft lip in a baby suffering from Cleidocranial Dysplasia.
A wide pelvic joint may also be seen in this condition. Additionally, there may be delayed growth of the pubic bone and a defect may be seen in the hip wherein the thigh bones are jutting towards the center of the body.
Cleidocranial dysplasia patients may also exhibit abnormalities in the development of teeth, with some missing, or extra teeth found in the jaw. These dental problems may alsio be associated with the development of enamel over the teeth as well. Teeth may be misaligned and misshaped, with the potential for cysts to develop within the gums.
The stature of the cleidocranial dysplasia patient is often shorter than other family members. Additionally, these individuals have tapered fingers, broad thumbs, flat feet, bow legs, or knock knees. They may also have scapulae or scoliosis.
Other possible complications may include a higher risk for ear infections, sinus infections, upper respiratory tract infections, and even hearing loss due to the accumulation of fluid in the middle ear.
Genetics
Cleidocranial Dysplasia is a genetic disorder that is caused only if there a mutation of the RUNX2 gene. This is a very rare disorder and is estimated to affect one in a million people worldwide. In fact, there have only been about 1,000 recorded cases in medical literature around the world.
Risk factors
Cleidocranial Dysplasia is inherited in a genetic pattern known as autosomal dominant inheritance. This refers to the point that a single altered gene present in one parent is enough to cause the medical condition in the baby. Genetic counseling must be undertaken before attempting pregnancy for people who are already suffering from the condition.
Should both parents have the mutation in their genes, the baby will be born with the condition. Comparatively, only one parent with the mutation will also have a chance of having a baby who will inherit a mild case of the disorder, or even escape the inheritance. Genetic testing can be done on the fetus to determine the possibility of inheritance and severity of the condition that the baby will face after birth.
The gene mutation responsible for cleidocranial dysplasia can also occur spontaneously. This refers to the fact that neither parent may be carrying the faulty gene, but the gene of the child may become mutated due to some unidentifiable reason. There is no way to avoid a spontaneous genetic mutation; however, general precautions must be taken to avoid situations that can cause genetic mutations.
While cleidocranial dysplasia is associated with the genetic mutation of the RUNX2 gene in the majority of cases, nearly 30% of the patients suffering from this condition do not have this genetic mutation.
The cause of the disorder is unknown in these cases. In fact, many of these individuals do not have a history of the disorder in their families.
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