A 68-year-old woman with chronic renal failure is being evaluated in the nephrology clinic. The nurse reviews her recent laboratory results and notes an elevated serum phosphorus level. Which statement best explains why patients with chronic renal failure are at increased risk for phosphorus retention?
- Chronic renal failure causes the adrenal glands to overproduce aldosterone, which retains phosphorus.
- Renal failure leads to excess parathyroid hormone suppression, which prevents phosphorus excretion.
- Damaged kidneys increase phosphorus reabsorption from the gastrointestinal tract.
- The kidneys are unable to adequately excrete phosphorus, causing it to accumulate in the blood.