What is the result of renal failure?

Renal failure, also known as kidney failure, refers to the condition in which the kidneys are unable to effectively filter waste products and excess fluids from the blood. This impairment leads to several complications, the most significant being the accumulation of toxins in the blood. Normally, healthy kidneys filter out waste materials such as urea, creatinine, and various other metabolites. When kidney function declines, these substances are not adequately cleared, resulting in their buildup in the bloodstream. This can cause a range of symptoms and health problems, including nausea, fatigue, and in severe cases, can lead to life-threatening complications.

The other options do not accurately reflect the condition of renal failure. Complete elimination of waste suggests the kidneys are functioning effectively, which contrasts with the very definition of failure. Increased urine production can occur in certain types of kidney issues but is not a general outcome of renal failure—most often, kidney failure results in reduced urine output. Lastly, enhancement of kidney function directly contradicts the nature of renal failure, as the kidneys' ability to filter and excrete waste is diminished rather than improved.