osteitis fibrosa disseminata


pol·y·os·tot·ic fi·brous dys·pla·si·a

the occurrence of lesions of fibrous dysplasia in multiple bones, commonly on one side of the body; may occur with areas of pigmentation and endocrine dysfunction (McCune-Albright syndrome). Synonym(s): multifocal osteitis fibrosa, osteitis fibrosa disseminata

McCune-Albright syndrome

An autosomal dominant condition (OMIM:174800) due to altered regulation of cAMP, endocrinopathy (e.g., hyperthyroidism) and hypophosphatemia.
Clinical findings
Precocious puberty, polyostotic (cystic fibrous dysplasia) spontaneous fractures at young age, café-au-lait spots on skin, ovarian cysts.
 
Lab
Cyclical 4–6-week fluctuations of plasma oestrogen; afflicted young girls have decreased gonadotropins, decreased response to LH-RH; increased testosterone, increased alkaline phosphatase.
 
Molecular pathology
Defects in GNAS, which encodes a G protein that modulates various membrane signalling cascasdes, cause McCune-Albright syndrome.
Management
Aromatase inhibitor testolactone.