Primary Hyperparathyroidism Due to Parathyroid Carcinoma of Ectopic Origin a Case Report

Case: A 43-year-old Hispanic woman, with no past medical history, who presents with arthralgias, myalgias, and generalized weakness. She started four days before admission with generalized headache, pressure-like and subjective fever associated with gingivorrhagia. Physical examination revealed a non-pruriginous maculopapular rash, predominantly in upper and lower extremities and diffuse abdominal tenderness on deep palpation diagnosing at that time dengue by positive serology. Within the initial assessment, the presence of hypercalcemia of 11.4 mg/dl called attention, thrombocytopenia of 45,000 and a mixed cholestatic and hepatocellular liver injury (AST 178 U/L, ALT 137 U/L, ALP 300 U/L, and GGT 345 U/L) with preserved renal function. Complimentary laboratory test revealed ionized calcium of 1.56 mmol/L, elevated PTH of 680.5 pg/ml, and low 25-hydroxyvitamin D of 4.7ng/dl. Tc-99m sestamibi scintigraphy reported abnormal focal uptake in the mediastinum (Figure 1). CT of the chest showed a mass in superior mediastinum, in the paratracheal region, 5.3 x 3.4 x 3.3 cm in size, with a solid and cystic component, and with heterogenous uptake of radiotracer, predominantly in the solid component (Figure 2). Supportive treatment is given for dengue, with clinical improvement and discharged with cinacalcet 30mg every 12 hours and follow up with Endocrinology. Fifteen days after discharge, patient presented to the ED with generalized weakness and drowsiness. On physical exam: Vital signs BP 113/98 mmHg, HR 94bpm, RR 21 rpm, Temp 36°C, alert and oriented x4, with bradypsychia, and diminished sensitivity and muscle strength 3/5 in upper and lower extremities, with mild tachycardia, and lungs clear to auscultation. Upon admission, laboratory tests revealed Hb 15.2 g/dl, MCV 86.2 fL, Hct 41.1%, leukocytosis of 22.26 K/ uL, with ANC 20.03, platelets 339,000 K/uL, glucose of 181mg/ dL, Cr 1.04 mg/dL BUN 15.5 mg/dL Urea 33.2 mg/dL AST 26 U/L, ALT 37 U/L, ALP 271 U/L, GGT 149 U/L, Na 137 mmol/L, K 2.42 mmol/L, Cl 91.8 mmol/L, Phosphorus 2.1 mg/dl, Calcium 19.3 mg/dl, PTH: 2791 pg/ml, and normal thyroid function test. She was started on IV hydration, cinacalcet, denosumab and intermittent renal replacement therapy in 4 sessions, without lowering serum calcium levels. PTH increased > 5000, surgical intervention was decided, but nevertheless, patient died 8 hours after surgery, in (Figures 3 & 4) are showed the patient’s PTH and calcium levels during hospitalization.