Bone Abstracts

The purpose of this presentation is to present the guidelines for recommending surgery for asymptomatic primary hyperparathyroidism, based on a workshop held in 2013. The indications for surgery were: i) a serum calcium more than 1 mg/dl (or 0.25 mmol/l) above the reference interval; ii) a low bone density (T-score −2.5 or less at the lumbar spine, total hip, femoral neck, or distal radius 1/3) or presence of vertebral fracture; iii) chronic kidney disease stage 3 (eGFR < 60 cc/min) or presence of kidney stones (X-ray, ultrasound or CT) or risk of kidney stones (high urinary calcium of 400 mg/day or 10 mmol/day, and positive kidney stone work-up); iv) age < 50. Both second and third generation parathyroid hormone assays may be used but it is important to establish reference intervals based on vitamin D-replete population. It was recognized that a proportion of patients with this disorder will have normal PTH but high serum calcium, and that a proportion will have normal serum calcium and a raised PTH (in the absence of obvious causes such as vitamin D deficiency and CKD), the so-called normocalcaemic hyperparathyroidism. Vitamin D deficiency is commonly associated with this disorder and should be treated as it may be linked to the severity of the disease. More than 10% or more of patients may have a genetic basis, especially individuals who are young, or have multiple glands affected, or have other endocrine disorders already. They also recognized the importance of searching carefully for occult kidney stones as there is some evidence that the risk of kidney stones is reduced by surgery, and for osteoporosis, as there is some evidence that fracture risk may be reduced by surgery.