Certified Hemodialysis Technician Practice Exam 2025 – All-in-One Guide to Exam Success

Elevated creatinine, blood urea nitrogen (BUN), and phosphorus levels are key indicators of renal failure, as they reflect the kidneys' inability to effectively filter waste products from the blood. In healthy kidneys, creatinine is produced from muscle metabolism and is usually excreted at a constant rate. BUN results from the breakdown of proteins in the body and also requires adequate kidney function for excretion. When kidney function declines, these waste products accumulate in the bloodstream, leading to elevated serum levels of both creatinine and BUN.

Phosphorus levels may also rise due to decreased excretion as kidney disease progresses, resulting in mineral imbalances that can have further health implications. Monitoring these serum abnormalities is crucial in assessing renal function and guiding treatment decisions for patients experiencing kidney failure.

Reduction in blood volume and low blood pressure readings can occur with different conditions and do not specifically indicate renal failure. A decreased white blood cell count could suggest other underlying health issues that aren't directly related to kidney function. Thus, the combination of elevated creatinine, BUN, and phosphorus levels specifically highlights impaired renal excretory ability, making this the most accurate answer regarding kidney failure indicators.