High calcium levels in the urine may be due to high vitamin D levels, chronic kidney disease, eating excess calcium, calcium leaks from the kidneys into the urine, sarcoidosis, use of diuretics and excess production of parathyroid hormone, notes the United States National Institutes of Health's MedlinePlus. Typically, elevated levels of calcium in the urine indicate the presence of an underlying condition, but a lab test is required to confirm.
Excess production of the parathyroid syndrome is the leading cause of elevated calcium in the blood, and this condition is known as primary hyperparathyroidism, notes UCLA Health System. People with this condition have a benign tumor in the parathyroid gland that causes calcium to leave the bone into the blood. Taking water pills, or diuretics, causes the kidney to hold calcium, preventing its removal through the urine and increasing the blood calcium level. People suffering from a chronic kidney disease are likely to have high levels of calcium in the blood due to reduced kidney function.
This condition is medically known as hypercalcemia, notes Mayo Clinic. It can lead to weak bones and also can interfere with the function of the brain and the heart. This condition also creates kidney stones. Its treatment depends on the underlying problem, and the symptoms may vary depending on its severity.