mccune  albright syndrome ( mas ) is a rare sporadic disease characterized by bone fibrous dysplasia , caf - au - lait skin spots and a variable association of hyperfunctional endocrine disorders . fibrous dysplasia ( fd ) , which can involve any part and combination of the craniofacial , axial , and appendicular skeleton , can range from an isolated , asymptomatic monostotic lesion discovered incidentally to a severe disabling polyostotic disease involving the entire skeleton and leading to progressive scoliosis , facial deformity , and loss of mobility , vision , and hearing . polyostotic fibrous dysplasia ( pfd ) is one of the subtypes of fibrous dysplasia , resulted from of an early embryonic postzygotic somatic activating mutation of gnas ( encoding the camp pathway - associated g - protein , gs ) , and is characterized by involvement of the skin , skeleton , and endocrine system . the proximal femur is often involved associated with shepherd s deformity , limb shortening , limping and sometimes pathologic fracture . endocrinopathies include : gonadotropin - independent precocious puberty resulting from recurrent ovarian cysts in girls and autonomous testosterone production in boys ; testicular lesions with or without associated gonadotropin - independent precocious puberty ; thyroid lesions with or without non - autoimmune hyperthyroidism ; growth hormone excess ; fgf23-mediated phosphate wasting with or without hypophosphatemia in association with fibrous dysplasia ; and neonatal hypercortisolism . a twenty - five - year old male patient presented to our clinic with recently occurring heart palpitations . he reported feeling pain in the right femur from the younger ages , without any trauma history , leading to difficulties with ambulation and limping occasionally . the patient was born after a trouble - free pregnancy with a birth weight of 3200 g and a height of 50 cm . as an infant , the pediatrician suspected him of undescended right testicle for which the patient underwent an exploratory laparotomy at the age of 10 years . none of the commonly ectopic location for undescended testicle was identified . physical findings of the patient at presentation were as follows : height : 197 cm , weight : 86 kg and arm span : 200 cm . cafe - au - lait skin spots with irregular borders , one with diameters of 105 cm on the left thigh ( picture 1 ) and one with diameters of 53 cm on the left calf were present ( picture 2 ) . he had right testicular agenesis , with a volume of 35 ml of the developed left testicle . he had insignificant hypotonia , heart murmur on cardiac auscultation and palpable liver edge 1 cm below the costal margin . the laboratory findings concerning hormones and electrolytes were as follows : serum prolactin , fsh , lh , cortisol and testosterone with normal values , ft4 , pth , alkaline phosphatase and calcium with elevated serum values , serum phosphate and tsh with decreased value . echocardiogram was performed revealing left ventricular hypertrophy , with initial thickness of the interventricular septum . systemic hypertension ( systolic pressures 90 to 145 mmhg , diastolic pressures 55 to 105 mmhg ) was confirmed . primary renal disease was excluded by normal values of plasma renin activity and aldosterone , as well as renal imaging studies . a pelvis radiograph revealed generalized reduction of bone density at this level , irregular ossification with areas of radiolucency surrounded by sclerosis most evident in his right femur . also areas of sclerosis of the ilium adjacent to the sacroiliac ( si ) joints were found on this x - ray ( image 1 ) . on the right hip - joint x - ray the proximal femur shows a diffusely abnormal irregular trabecular pattern with areas of decreased and increased osseous density and ground - glass opacity ( image 2 , 3 ) . differential diagnosis of the lesions described should be made with multiple lytic metastases , giant aneurysmal cyst , giant cell tumors of the bone , neurofibromatosis type i , osteofibrous dysplasia , mazabraud syndrome . there are some useful but not specific findings for differentiating fibrous dysplasia from other entities , even though there is marked variability in the appearance of the bone lesions , and they can often resemble a tumor . on t1-weighted images there is heterogeneous signal , usually intermediate and high on stir ( image 4 ) ; on t2-weighted images the signal is heterogeneous , usually low , but may have regions of higher signal ; on t1 with contrast it can be heterogeneous contrast enhancement ( images 5,6,7 ) . until this moment the diagnosis was hyperthyroidism with secondary systemic hypertension , fibrous dysplasia of the right sacrum , ilium and femur , secondary osteitis condensans ilii , cafe - au - lait skin spots and right testicular agenesis . all these entities associated , except testicular agenesis , suggest a diagnosis of mccune albright syndrome that could be confirmed by genetic analysis . due to the variability of appearance of fibrous dysplasia the potential differential diagnosis is really complex , but is significantly influenced by the dominant pattern . giving the clinical presentation of our patient and the laboratory and mri findings a differential diagnosis should be made with : neurofibromatosis type i ( nf1 ) and fd / mas have several common features , including caf - au - lait skin spots and skeletal abnormalities . skin findings in nf1 include six or more caf - au - lait macules , which are generally smooth - bordered as opposed to the irregularly - bordered lesions seen in fd / mas . skeletal features of nf1 include kyphoscoliosis , sphenoid dysplasia , cortical thinning of long bones , and dysplasia of the tibia which may result in pseudarthrosis . distinct features of nf1 include tumors of the nervous system such as neurofibromas and optic gliomas , pigmented iris hamartomas , and axillary freckling . giant cell tumors of the bone are acquired lesions which have similar histopathological features to fibrous dysplasia , including proliferation of bone marrow stromal cells and the presence of multiple multinucleated giant cells . the mri aspect of bone metastases in t1-weighted images is similar to fibrous dysplasia lesion but after contrast administration there is important enhancement of contrast in case of bone metastases . furthermore the bone edema , periosteal reaction and soft - tissue mass is usually identified in oncologic patients with bone metastases . osteitis condensans ilii is represented by the sclerosis of the ilium adjacent to the sacroiliac ( si ) joints and develop secondary to antalgic position for protecting the painful femur . the main differential diagnosis is sacroiliitis , but in osteitis condensans ilii the si joints are normal with no irregularity , erosions or loss of joint space ( image 6 ) . after the initial diagnosis , all individuals with fd / mas should be evaluated to determine the extent of disease . he also had chronic osteoporosis determined by hyperparathyroidism , which in addition to fibrous dysplasia of the right femur increases the possibility of insufficiency fractures at any moment . moreover , to avoid these complications and because there are no available medical therapies capable of altering the disease course in fibrous dysplasia , current management is focused on optimizing function and minimizing morbidity related to fractures and deformity . according to treatment guidelines , hormonal medication and bisphosphonates
mccune  albright syndrome is a rare sporadic disease characterized by bone fibrous dysplasia , caf - au - lait skin spots and a variable association of hyperfunctional endocrine disorders . 
 fibrous dysplasia ( fd ) , which can involve the craniofacial , axial , and appendicular skeleton , may range from an isolated , asymptomatic monostotic lesion to a severe disabling polyostotic disease involving the entire skeleton . a twenty - five - year old male patient presented to our clinic with recently developed heart palpitations . 
 he had also been feeling pain in the right femur since he was younger , without any trauma history , leading to difficulties of ambulation and limping occasionally . 
 his physical examination revealed caf - au - lait spots with irregular borders and right testicular agenesis . 
 laboratory findings identified hyperthyroidism with hyperparathyroidism . 
 radiographs of the pelvis revealed multiple lytic lesions of the right femur and magnetic resonance imaging ( mri ) characterized these lesions as specific to fibrous dysplasia of the bone , without any insufficiency fracture at this level.the association of caf - au - lait skin spots with bone fibrous dysplasia , and hyperthyroidism in this patient suggested the diagnosis of mccune  albright syndrome .