Polyostotic fibrous dysplasia
Polyostotic Fibrous Dysplasia is a genetic disorder of bones, skin pigmentation and hormonal problems along with premature puberty. more...
Within the syndrome there are bone fractures and deformity of the legs, arms and skull, different pigment patches on the skin, and early puberty with increased rate of growth. Polyostotic fibrous dysplasia is usually caused by mosaicism for a mutation in a gene called GNAS1.
Polyostotic Fibrous Dysplasia has different levels of severity. For example one child may be entirely healthy with no outward evidence of bone or endocrine problems, enter puberty at close to the normal age and have no unusual skin pimgentation. The complete opposite of that would be children who are diagnosed in early infancy with the obvious bone disease and obvious increased endocrine secretions from several glands.
Approximately 20-30% of fibrous dysplasias are polyostotic and two thirds of patients are polyostotic before the age of ten.
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