- McCune-Albright syndrome
Infobox_Disease
Name = McCune-Albright syndrome
Caption =
DiseasesDB = 7880
ICD10 = ICD10|Q|78|1|q|65
ICD9 = ICD9|756.54
ICDO =
OMIM = 174800
MedlinePlus = 001217
eMedicineSubj = ped
eMedicineTopic = 1386
MeshID = D005359McCune-Albright syndrome (polyostotic fibrous dysplasia), described in
1937 byDonovan James McCune andFuller Albright , [WhoNamedIt|synd|1844] is agenetic disorder of bones, skinpigmentation and hormonal problems along with prematurepuberty .ymptoms
It is suspected when two of the three following features are present:
* (autonomous)
endocrine hyperfunction such asprecocious puberty
*Fibrous dysplasia
*Café-au-lait spot sPresentation
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 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 pigmentation. 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.
Polyostotic fibrous dysplasia is usually caused by mosaicism for a mutation in a gene called GNAS1 (Guanine Nucleotide binding protein, Alpha Stimulating activity polypeptide 1).
The syndrome shows a broad spectrum of severity. The disease frequently involves the
skull and facial bones,pelvis , spine and shoulder girdle. The sites of involvement are thefemur (91%),tibia (81%), pelvis (78%), ribs, skull and facial bones (50%), upper extremities, lumbar spine,clavicle , and cervical spine, in decreasing order of frequency. The craniofacial pattern of the disease occurs in 50% of patients with the polyostotic form of fibrous dysplasia.Genetics
Genetically, there is a post-zygotic
mutation of thegene GNAS1 which is involved inG-protein signalling. This mutation, often amosaicism , preventsdownregulation of cAMP signalling.Notable cases
The disease made headlines in December, 2005 when a
Haiti an teen afflicted with the disease,Marlie Casseus , underwent a 17-hour emergency surgical procedure to remove a 16 pound tumour-like growth of bone from her face. A series of operations at Holtz Children's Hospital inMiami, Florida restored the child's face to a more normal proportion. [cite web |url=http://www.internationalkidsfund.org/ikf_kids/details.cfm?KD_ID=123 |title=Marlie Casseus |accessdate=2007-07-14 |format= |work=]ee also
*
Fibrous dysplasia References
External links
* [http://www.medterms.com/script/main/art.asp?articlekey=11362 Medterms.com]
* [http://www.le.ac.uk/genetics/maa7/GNAS1/ GNAS gene]
* [http://www.rarediseases.org/search/rdbdetail_abstract.html?disname=McCune%20Albright%20Syndrome NORD]
* [http://www.gfmer.ch/genetic_diseases_v2/gendis_detail_list.php?cat3=189 GFMER]
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