Parathyroid Adenoma Complicated with Severe Hypercalcemia, Encephalopathy and Pancreatitis

ABSTRACT

Primary hyperparathyroidism is the most frequent cause of hypercalcemia in adults. Primary hyperparathyroidism generally leads to mild-moderate hypercalcemia. Severe hypercalcemia in these cases is rare. Coexistence of severe hypercalcemia and hypercalcemic encephalopathy is very unusual with very limited number of reported cases. Our case is a 50-year-old female who presented to the emergency department with the complaints of nausea and severe abdominal pain. Her serum calcium level was 19.7 mg/dL (8.8-10.2 mg/dL) and her PTH level was 73.5 ng/dL (15-65) on presentation. After her hospitalization, she was treated with saline infusions and furosemide, however, her calcium level increased to 22.4 mg/dL. Her calcium levels were also refractory to subcutaneous calcitonin 200 mg twice a day and zoledronic acid 4 mg. Ultrasonography of the neck revealed a 3.2x2.7x4.6 cm mass suspicious for a left parathyroid adenoma hardly being distinguished from a left thyroid nodule. Considering her general situation getting worse despite maximum medical treatment, she underwent an emergency parathyroidectomy and total thyroidectomy. Early postoperatively, the patient’s general condition deteriorated reaching a precoma state. Cranial computed tomography (CT) at this point revealed periventricular ischemia compatible with metabolic encephalopathy. During the follow-up postoperatively, the patient’s serum calcium levels normalized eventually requiring active vitamin D and calcium pills and she no longer had symptoms of encephalopathy. The pathology specimen was reported as a parathyroid neoplasm compatible with atypical parathyroid adenoma. Although mild-moderate hypercalcemia is frequent in primary hyperparathyroidism, it should be noted that it can be severe and refractory to maximum medical treatment requiring emergency surgical intervention. In addition, not being one of the most frequent reasons, severe hypercalcemia due to primary hyperparathyroidism should be considered as an important cause of metabolic encephalopathy.