Primary hyperparathyreoidism - diagnostic procedures and management

Abstract

Hypercalcemia as a laboratory result is often diagnosed during evaluation for osteoporosis. Any form of hypercalcemia should be evaluated further. Owing to fluctuating calcium levels, the measurement should be repeated and corrected for elevated albumin levels by calculation or by measuring ionized calcium. In the diagnosis of primary hyperparathyroidism, measurement of parathyroid hormone, creatinine/glomerular filtration rate, phosphate, 25-OH vitamin D3 and 24-hour urine values are essential for differential diagnosis. Kidney ultrasound is used to detect nephrocalcinosis or kidney stones, and dual-energy X-ray absorptiometry (DXA) to determine bone mineral density (BMD) at the lumbar spine, femoral neck, total femur, and distal forearm. Complete cure is only possible through surgical resection of the adenoma(s). The indication for surgery is dependent on the age of the patient, existing complications, and the patient's preference. Diagnostic imaging should only be performed if surgery is planned. Typically, neck ultrasound and 99mTc MIBI scintigraphy are sufficient to localize the parathyroid adenoma. Presurgical diagnostic evaluation of the thyroid is reasonable for surgical planning. Vitamin-D deficiency should be normalized before surgery. Postsurgical calcium and vitamin-D administration will prevent postsurgical hypocalcemia and hungry-bone disease, and may optimize the outcome of BMD. Treatment of osteoporosis without fractures might not be necessary, owing to normalization of BMD several years after parathyroid surgery. The continuation of specific anti-osteoporotic treatment with bisphosphonates post-surgery did not have any advantage and hence cannot be recommended.