hyperparathyroidism due to parathyroid abnormalities are classified into three forms : primary , secondary , and tertiary .
parathyroid adenoma accounts for about 85% of all cases of hyperparathyroidism , considering all the forms : primary , secondary and tertiary .
other less prevalent causes include parathyroid hyperplasia ( 15% ) and carcinoma ( 3 - 4% ) .
however , acute primary hyperparathyroidism , or parathyroid crisis ( pc ) , is rare .
parathyroid crisis is characterized by life - threatening hypercalcemia of a sudden onset in subjects with phpt .
we describe a patient with pc secondary to a giant intrathyroidal parathyroid adenoma who presented with progressive neurological symptoms , nausea and vomiting without medical response to treatment .
a 19-year - old female patient was admitted to the orthopedics department for supra - acetabular fibrous dysplasia treatment .
after orthopedic surgery , during the second postoperative day she began to suffer from lethargy , nausea , vomiting , and abdominal pain . also , the patient reported muscle weakness , fatigue and a worsening of depressive symptoms .
a blood analysis was performed which showed elevated ca ( 14.2 mg / dl , normal laboratory level 8.8 - 10.2 mg / dl ) .
the serum phosphorus was low ( 3.99 ng / ml , normal laboratory level 4.0 - 19.0 ng / ml ) with an increased alkaline phosphatase level ( 171 ui / l , normal laboratory level 20 - 90
endocrine evaluation showed elevated parathyroid hormone ( pth ) ( 1207.0 pg / dl , normal laboratory 7 - 82 pg / dl ) .
an urgent ultrasonography was requested and showed a 47  22 mm nodule in the left thyroid lobe .
after two days of intensive medical treatment , the ca levels had not decreased and the clinical situation of the patient remained similar or even worse . because of life - threatening hypercalcaemia and a poor response to medical treatment , she directly underwent surgery after a consensus decision between the endocrinologists and the surgeons .
a hemithyroidectomy was performed assuming it was an intrathyroiidal adenoma and without time for performing a fine needle aspiration because of the patient 's situation . during the surgical procedure ,
a superior parathyroid gland was observed and not resected . at the end of the hemithyroidectomy ,
the specimen was open and a clear intra - thyroidal adenoma surrounded by thyroid tissue was observed [ figure 1 ] .
unfortunately , intraoperative pth and anathomopathological analyse were avaible but were not used according to the intraoperative findings . on the final anatomopathological examination ,
it had a maximum diameter of 3 cm and the whole specimen weighted 70 g. the postoperative course was uneventful .
the patient received doses of calcium iv during the first day and oral intake began at day two .
oral calcium was then given to the patient in the postoperative period until the fist visit at the outpatient clinic . during follow - up ,
the risk of developing this disease increases with a peak incidence between 50 and 60 years , whereas phpt in children and adolescents is a rare condition .
parathyroid crisis is characterized by life - threatening hypercalcemia of sudden onset in subjects with phpt .
it has been reported that changes in mental status are characteristic features of hypercalcemic crisis .
moreover , she had muscle weakness . although neuromuscular manifestations have been described previously , the pathophysiology of these manifestations is not yet clear .
moreover , in pc , as a potentially lethal condition , emergent parathyroidectomy has been advocated .
certainly , it has been emphasized that expeditive parathyroidectomy is the cornerstone treatment of patients with pc .
there is no clear relationship between surgery and the beginning of toxic , urgent hypercalcaemia . in surgical series
there is an estimated reported prevalence of intrathyroidal parathyroid adenoma that varies from 1.4 - 6% .
according to embryology , parathyroid glands originate from the third and fourth branchial pouches . after this
, the glands caudally migrate to their final positions . any problems during this migration can lead to the glands settling in an anomalous location , even in the thyroid tissue . in a recent study , localization of most of the adenomas ( 70.6% )
was shown to be on the right side and on the lower third of the thyroid lobes .
this study also reported that intrathyroidal parathyroid adenomas were present in 3% of patients submitted for parathyroidectomy .
however , reports of a giant intrathyroidal parathyroid adenoma in the literature are exceptional . it has been noted that the weight of the adenoma correlates with the severity of the pc .
gasparri et al . , found that in a patient with a serum calcium level higher than 15 mg / dl , the mean weight of the removed glands was 4.9 g , whereas it was 2.1 g in patients with serum calcium levels lower than 15 mg / dl . nevertheless , giant parathyroid adenomas are rare .
, reported that adenomas heavier than 3.5 g accounted for 7.2% of their series of phpt .
differential diagnoses , when very high levels of pth are present , must be established with parathyroid carcinoma .
parathyroid carcinoma is a rare malignancy with an incidence rate of less than 1% in all patients surgically treated for primary hyperparathyroidism . to the best of our knowledge
the clinical manifestations of hyperparathyroidism in parathyroid carcinoma are usually more severe than in patients with parathyroid adenoma .
parathyroid crisis is an emergency because high levels of calcium pose a life - threatening situation for patients .
. however , changes in mental status are prevalent , hence , the serum calcium level must be determined in any patient with unexplained central nervous dysfunction . once the patient with pc has been stabilized , expedited parathyroidectomy must be performed .
 primary hyperparathyroidism ( phpt ) is not an uncommon endocrine disorder . 
 however , acute primary hyperparathyroidism , or parathyroid crisis ( pc ) , is a rare clinical entity characterized by life - threatening hypercalcemia of a sudden onset in patients with phpt . 
 we describe a patient with pc who presented with acute worsening of depressive symptoms , nausea and vomiting , and required emergency surgery . 
 serum calcium , alkaline phosphatase , and parathyroid hormone were elevated and serum phosphorus was low . 
 an emergency hemithyroidectomy was performed because of none medical control of hypercalcemia . 
 a giant intrathyroidal parathyroid adenoma was diagnosed . 
 phtp can be a life - threatening situation for patients , requiring immediate surgical treatment . 
 a giant intrathyroidal parathyroid adenoma is an uncommon cause of pc . 
INTRODUCTION
CASE REPORT
DISCUSSION
CONCLUSION