What are the parameters that predict the development of nephrolithiasis and osteoporosis in patients with primary hyperparathyroidism?

INTRODUCTION: Primary hyperparathyroidism (PHPT) is associated with an increased risk of nephrolithiasis and osteoporosis, and predicting the development of these diseases will reduce PHP-related morbidities.
METHODS: A total of 311 patients with PHPT due to parathyroid adenoma were evaluated retrospectively. The patients were divided into groups, as patients with and without nephrolithiasis and those with and without osteoporosis. Demographic and biochemical variables that could predict the development of nephrolithiasis and osteoporosis in these groups were examined.
RESULTS: Nephrolithiasis was observed in 24.44% of 311 PHPT patients. Serum creatinine (Cr), serum calcium (Ca), adjusted Ca (adj Ca), albumin and 24-hour urinary phosphorus (24h uP) levels were higher, and serum P-value was significantly lower in patients with nephrolithiasis than those without nephrolithiasis. In the Receiver Operating Characteristic (ROC) analysis, serum Cr ≥0.66 mg/dl, adj Ca ≥10.72 mg/dl, serum P ≤2.71 mg/dl and 24h uP ≥635 mg/day cut-off values were found to have high sensitivity and low specificity values on the risk of developing nephrolithiasis. Of all patients, 43.09% had osteoporosis, and it was determined that only ≥50.50 years (sensitivity 81.34%, specificity 49.51%) and intact parathyroid hormone ≥ 201.50 pg/mL (sensitivity 75.14%, specificity 41.04%) values could predict osteoporosis (Area Under the ROC curve ranged from 0.57 to 0.67).
DISCUSSION AND CONCLUSION: While biochemical parameters are useful in predicting nephrolithiasis in patients with PHPT, the development of osteoporosis seems to be less related to biochemical parameters.