CNN Exam- Chronic Kidney Disease Exam Questions and Answers 100% Pass

In patients with elevated calcium levels a lower dialysate concentration will be needed to remove excess calcium. Conversely, if patients need calcium, a dialysate concentration of 3.5 mEq/L will provide calcium to the patient. Initial therapy to raise the serum calcium level is through both calcium and vitamin D supplementation. Describe the kidney's role in calcium and phosphorus homeostasis - Answer- The kidney is instrumental in excreting excess phosphorous and producing the active form of vitamin D, called calcitriol. Calcitriol is a hormone which travels to the gut and aids in both phosphorus and calcium absorption. Moreover, calcium phosphorus is regulated by the hormones PTH (parathyroid hormone). PTH is released from the parathyroid gland and functions to elevate serum calcium levels and lower phosphorus levels. ***Note that the kidneys are involved in both phosphorus excretion (under influence of PTH) and phosphorus absorption via calcitriol. Discuss the pathophysiology of aluminum toxicity in patients with chronic kidney disease - Answer- Aluminum is excreted by the kidneys. In patients with renal disease, the ability to excrete aluminum is hindered. Aluminum toxicity was a much larger problem when aluminum based phosphate binders were used. The aluminum would be absorbed by the gut and accumulate over time. Aluminum causes the following abnormalities: - acute toxicity - dementia - osteomalacia - anemia - hypercalcemia (by displacing calcium in bony matrix) Treatment of acute aluminum toxicity is via hemodialysis with low aluminum dialysate concentration. Osteomalacia, dementia, anemia and hypercalcemia are products of chronic exposure to aluminum. Prevention is huge with avoidance of aluminum based phosphate binders and frequent monitoring of dialysis water system for elevated aluminum levels. Describe the role of parathyroid hormone (PTH) on calcium and phosphorus - Answer- PTH is stimulated by 2 mechanisms: either a low serum calcium level or elevated phosphorus PTH acts to increase serum calcium and lower phosphorus. It increases calcium by 2 methods: - Stimulates the release of calcium from bone (body's reserve of calcium stores) - Stimulates the kidney to release calcitriol (active form of Vitamin D). Calcitriol will raise the serum calcium level by increasing calcium absorption in the gut. PTH also acts to decrease serum phosphorus. Accomplishes this by acting on the kidneys to excrete phosphorus in the urine. In patients with CKD, PTH is elevated because the kidneys do not respond appropriately. Kidneys can neither produce