mccune  albright syndrome ( mas ) is a rare sporadic disorder with an estimated prevalence between 1/100,000 and 1/1,000,000 , characterized by the triad of polyostotic fibrous dysplasia ( fd ) , caf - au - lait maculae and hyperfunctional endocrinopathies . we report another rare case who had fd and precocious puberty with hyperthyroidism and was treated with radioiodine , adding to the existing literature that documents only six instances of radioablation in mas . a 7-year - old female child presented with precocious menstruation , caf - au - lait spots and breast development since last 2 years . apart from caf - au - lait spots , prominent breasts and mild facial asymmetry , she had raised pulse rate of 110/min and diffuse enlargement of both lobes of the thyroid gland . thyroid function tests showed the following results : t3 : 221 ng / dl ( normal 60181 ng / dl ) ; t4 : 7.9 g / dl ( normal 4.512.6 g / dl ) and thyroid stimulating hormone ( tsh ) : 0.12 iu / ml . serum prolactin was 44.91 ng / ml ( normal 4.7923.3 ng / ml ) , testosterone 43.65 pg / ml ( normal 12.5166 pg / ml ) , luteinizing hormone ( lh ) 0.07 iu / ml ( normal 0.16 iu / ml ) , follicle stimulating hormone ( fsh ) ? 0.1?miu / ml 0.1 miu / ml ( normal 3.512.4 ) , estradiol 43.65 pg / ml ( normal 12.516.6 pg / ml ) , and parathormone ( pth ) 42 pg / ml ( normal 1568 pg / ml ) . growth hormone ( gh ) measured 4.98 ng / ml ( normal up to 13 ng / ml ) , insulin - like growth factor 1 ( igf-1 ) was 460 ng / ml ( normal 57316 ng / ml ) , and serum 25(oh)2 vitamin d3 level was 48.54 nmol / l ( normal 171536 nmol / l ) and adrenocorticotropic hormone ( acth ; taken at the same time ) was < 1.35 pg / ml . x - ray showed multiple ground glass opacities with lytic and sclerotic areas in long bones and skull bones [ figure 1 ] . computed tomography ( ct ) of the abdomen revealed mesenteric lymphadenopathy , with no abnormality in adrenal glands . magnetic resonance imaging ( mri ) showed altered signal intensity lesion expanding the sphenoid bone , bilateral frontal and left maxilla with normal pituitary gland . tc99m - methylene diphosphonate ( mdp ) bone scan revealed intensely increased tracer uptake in the frontal bone , left maxilla , left side of mandible , left humerus , radius , shaft of both femur and tibia [ figure 1 ] . radioactive iodine-131 uptake ( raiu ) by the thyroid gland at 24 hours was 44.3% and tc99m - pertechnetate scan revealed diffusely enlarged thyroid gland with increased trapping function [ figure 2 ] . she was treated with 5 mci of radioiodine ( empirical dose ) along with inj . letrozole . on follow - up at 3 months , the patient improved symptomatically and the thyroid function tests were within normal limit : t3 : 1.74 ng / ml ( normal 0.82 ng / ml ) ; t4 : 8.92 g / dl ( normal 4.812.7 g / dl ) and tsh : 2.9 iu / ml ( normal 0.274.2 iu / ml ) . radiographs of the described patient showing expansion of the diploic space of the left greater wing of sphenoid , body of sphenoid , occiput and the left frontal bone , along with expansion of the meta - diaphyseal region and mixed lytic sclerotic lesions in the femur and tibia on the left side , expansion of the first metacarpal on the left side , and also in the left humerus and the radius tc99m - mdp whole body bone scan in ( a ) anterior and ( b ) posterior views showing increased osteoblastic activity in the left frontal , sphenoid , maxillary , occipital and bilateral parietal bones along with left humerus , forearm bones , femur on both sides and left tibia . tc99 m pertechnetate thyroid scan ( c ) of the same patient showing diffusely increased trapping in both lobes of the thyroids sallum et al . , in their review and literature search , reported 85 cases of hyperthyroidism with mas . mas associated thyroidopathies are attributed to post - zygotic activating mutation of camp regulating protein , gnas1 gene product gs , wherein arginine is replaced by another amino acid at position 201 . this leads to constitutive activation of adenylate cyclase , resulting in camp overproduction and consequent growth of thyrocytes and hormone hypersecretion . therefore , preferable mode of treatment for mas associated hyperthyroidism appears to be total surgical ablation or radioiodine therapy . literature review shows that the remission rates with antithyroid drugs even in grave 's disease are usually less than 3040% and even lesser ( ~17% ) in pre - pubertal children . children aged 1 year have also been treated with radioiodine . besides , no case of second malignancy has been reported in the literature so far following treatment with iodine for thyrotoxicosis . therefore , keeping in view the above aspects , radioiodine was advocated for this child . hyperthyroidism with or without goiter in the context of mas is considered rare , but is well described . increased morbidity due to recurrent hyperthyroidism after withdrawal of antithyroid drugs and complications during surgical removal necessitate ablation with radioactive iodine , the option which is most suitable for definitive management .
mccune  albright syndrome ( mas ) is a sporadic disease characterized by polyostotic fibrous dysplasia ,  caf - au - lait  spots and hyperfunctional endocrinopathies . 
 pathophysiological basis is activating mutation of the gene that encodes the alpha subunit of gs membrane protein that stimulates the intracellular production of camp , conferring autonomous secretion of the gland in particular . 
 one of the uncommon endocrine manifestations is hyperthyroidism . 
 we present a patient who had caf - au - lait spots , polyostotic fibrous dysplasia and hyperthyroidism . 
 she was treated with radioactive iodine for the symptoms of hyperthyroidism and subsequently relieved from hyperthyroid features .