Endocrine Abstracts

Primary Hyperparathyroidism (PHPT) is the most common disease among parathyroid disorders compared to Chronic Hypoparathyroidism, Calcium Sensor disorders (loss or gain of function mutations) or Parathyroid Cancer. The clinical presentation of PHPT has changed dramatically after the increased accessibility to biochemical analyses. The diagnosis is today often made by change in patients without specific symptoms. Operative treatment is always an option and recommended in patient with markedly increased calcium levels or typical symptoms. Bone metabolism in PHPT has been systematically investigated. Bone turnover is increased with a reversible bone loss at the trabecular surface, whereas there seems to be a non-reversible loss at the cortical level. Epidemiological and observational studies have demonstrated increased fracture rate in PHPT, and long term longitudinal studies have revealed a significant bone loss primarily at cortical sites with observation. Thus, diagnostic osteoporosis by DXA or low energy fractures is regarded as treatment indication (operation) even in the mildest cases. The primary treatment of PHPT is surgical removal of the enlarged parathyroid mass, most often being a parathyroid adenoma. Surgery (or anti-resorptive, medical treatment) will decrease bone turnover, filling the enlarged remodeling space and thereby in theory normalize fracture rate. However, only few prospective studies have looked into the benefit of operation versus conservative observation without intervention in PHPT. Observational data and recent prospective, randomized studies indicate that bone mass might become critical low with prolonged observation. In alignment, there seems to be a treatment effect on fracture rate with surgical treatment. Most patients with PHPT will present with few if any symptoms, high normal or slightly increased calcium levels with only moderately elevated PTH. Differential diagnoses must be ruled out and familiar or syndromic forms identified. An increased awareness on bone mass and fracture rate in patients to be followed without intervention is recommended.