Calcium-Ipth Axis and Primary hyper parathyroidism: a Study on Recurrent Kidney Stone Formers

Abstract

Objectives: This study aims to provide insights into the role of the calcium-iPTH axis and hyperparathyroidism in recurrent kidney stone formation.

Methods: The prospective cohort study investigated recurrent kidney stones in patients with a history of at least three episodes within two years, conducted at Shaikh Zayed Hospital in Lahore. A total of 54 adult participants, aged 18 to 65, were selected using a nonprobability, convenient sampling technique. Initial biochemical screenings included serum calcium, phosphorus, iPTH, vitamin D levels, and 24-hour urine collections. Renal ultrasonography assessed stone burden, while participants with elevated serum calcium and iPTH underwent further imaging to identify primary hyperparathyroidism. Confirmed cases of parathyroid adenoma were offered parathyroidectomy, with the surgical method based on imaging results. Data analysis utilized SPSS software, with continuous variables expressed as mean ± SD and categorical variables as frequencies. The study also explored the correlation between iPTH levels and stone recurrence through Pearson correlation and multivariate regression analysis.

Results: The study consists of 55.6% males and 44.4% females, with patients experiencing an average of 3.7 episodes in the last two years. Hypercalcemia was present in 74.1% of patients, and 66.7% had PHPT. Treatment for PHPT was effective, with 75% of patients not developing stones post-surgery. Higher levels of iPTH and serum calcium correlate positively with stone recurrence, while frequent urination and bone health issues are also strong indicators. The regression model shows that past episodes of kidney stones and elevated iPTH levels are strong predictors of future recurrence, while treatment significantly reduces the risk.

Conclusions: The calcium-iPTH axis and primary hyperparathyroidism play a significant role in recurrent kidney stone formation. Elevated iPTH and serum calcium levels predict recurrence, with higher iPTH levels correlated with kidney stone frequency.