[Study of diagnostic value of natremia in a cohort of patients with hypercalcemia].

INTRODUCTION

Hypercalcemia is a common pathological condition in clinical practice. The two most common causes are primary hyperparathyroidism and cancer. SIADH is often encountered in cancer cases and is the most common cause of hyponatremia. The aim of this study is to evaluate serum sodium levels in a cohort of patients with hypercalcemia and consider its predictive value in determining the origin of this hypercalcemia.

MATERIALS AND

METHODS

We performed a retrospective study on a series of 15.284 blood tests among adult patients with hypercalcemia. After selection, the study population had 151 patients. We studied mainly serum sodium and etiology of hypercalcemia in our population.

RESULTS

We observed a statistically significant association between the presence of hyponatremia and the neoplastic etiology of hypercalcemia. This association persisted after exclusion of patients under treatment with loop diuretics. Conversely, there was no association between hypernatremia and cancer-related hypercalcemia. Among 151 patients with hypercalcemia, 16 presented hyponatremia and 7 with hypernatremia. SIADH was the main cause of hyponatremia. We performed univariate and multivariate logistic regression showing the association between the presence of cancer and the presence of hyponatremia.

CONCLUSION

Our study shows that there is an association between the presence of hyponatremia and neoplastic origin of hypercalcemia. Besides, the association described between hyponatremia and cancer is not faulted by the presence of hypercalcemia, a potential cause of acquired nephrogenic diabetes insipidus.