In a patient with chronic renal disease, what set of serum findings indicates secondary hyperparathyroidism?

In a patient with chronic renal disease, secondary hyperparathyroidism is primarily a compensatory response to alterations in calcium and phosphate metabolism. The kidneys are less able to excrete phosphate, leading to hyperphosphatemia, which contributes to decreased serum calcium levels due to the relationship between calcium and phosphate – as phosphate levels increase, calcium levels tend to decrease.

In this scenario, there is an increased secretion of parathyroid hormone (PTH) as the body attempts to maintain normal calcium levels despite the impaired kidney function. Therefore, the findings of increased parathyroid hormone, decreased calcium, and increased phosphate are indicative of secondary hyperparathyroidism.

This combination aligns well with the physiological response to chronic renal failure and provides a clear understanding of the mineral and hormonal imbalances that occur in this condition. Other options would misrepresent the condition or lack the characteristic elevations and depressions in these respective substances seen in secondary hyperparathyroidism.