How does hypercalcemia affect the kidneys?

Hypercalcemia, which is characterized by elevated calcium levels in the blood, can significantly impact kidney function. One of the primary effects of this condition is an increased risk of kidney stones and nephrocalcinosis. When there is an excess of calcium in the bloodstream, the kidneys filter out the surplus calcium, which can lead to its precipitation in the renal tubules and interstitial tissue, forming stones and calcifications. This process can compromise renal function and may also contribute to urinary obstruction and infection, further complicating kidney health.

In the context of renal function, hypercalcemia does not improve kidney filtration; in fact, the kidneys may struggle to process the excess calcium, leading to various complications. Additionally, hypercalcemia does not have a neutral impact on renal function; it actively promotes adverse conditions rather than leaving renal processes unchanged. Similarly, it does not decrease urine concentration; rather, hypercalcemia can potentially lead to nephrogenic diabetes insipidus, which disrupts the kidneys’ ability to concentrate urine effectively, albeit indirectly.

Therefore, the correct option highlighting that hypercalcemia can lead to kidney stones and nephrocalcinosis reflects the serious complications that arise from elevated calcium levels and their effects on kidney health.