1.
Which ONE of the following statements about the use of calcium containing-phosphate binders (CCPB) is TRUE?
Correct Answer
A. Patients who develop hypercalcemia on CCPB tend to have low bone density, suggesting reduced capacity for bone to buffer calcium loads.
Explanation
Patients who develop hypercalcemia on CCPB tend to have low bone density, suggesting reduced capacity for bone to buffer calcium loads. This statement suggests that patients with low bone density are more susceptible to developing hypercalcemia when using calcium-containing phosphate binders. This implies that these patients have a decreased ability to regulate and store calcium in their bones, leading to higher levels of calcium in the blood.
2.
Which ONE of the following statements BEST characterizes the effects of calcimimetic agent in modifying abnormalities in divalent ion metabolism in patients with renal failure?
Correct Answer
D. Calcimimetics reduce intact PTH levels while concurrently reducing Ca PO4 product.
Explanation
Calcimimetics are drugs that are used to treat abnormalities in divalent ion metabolism in patients with renal failure. The correct answer states that calcimimetics reduce intact parathyroid hormone (PTH) levels while concurrently reducing Ca PO4 product. This means that calcimimetics effectively lower PTH levels, which helps to regulate calcium and phosphate levels in the body. By reducing both PTH and Ca PO4 product, calcimimetics help to restore balance in divalent ion metabolism in patients with renal failure.
3.
A 54-yr-old Caucasian man presents with two large areas of skin necrosis on his left thigh. He has been treated with hemodialysis for the past 6 yr for chronic kidney disease secondary to polycystic kidney disease. He has received intermittent, small, oral doses of calcitriol but has developed hypercalcemia to 12.0 mg/dl. His physical examination is unremarkable except for moderate obesity and for intact pulses throughout his lower extremities. The necrotic areas of skin are superficial. Laboratory studies revealed: calcium, 9.6 mg/dl; phosphate, 5.6 mg/dl; immunoreactive parathyroid hormone, 100 pg/ml.Which ONE of the following choices BEST explains this clinical condition?
Correct Answer
A. CalcipHylaxis associated with adynamic bone disease.
Explanation
Calciphylaxis is a rare but serious condition characterized by calcification and necrosis of small blood vessels in the subcutaneous tissue. It typically occurs in patients with end-stage renal disease and is associated with high levels of calcium and phosphate. Adynamic bone disease is a condition in which there is low bone turnover, resulting in decreased bone mineralization. In this case, the patient's hypercalcemia and hyperphosphatemia, along with his history of chronic kidney disease and calcitriol therapy, suggest that the calciphylaxis is associated with adynamic bone disease.
4.
Which ONE of the following statements regarding the measurement of serum parathyroidhormone (PTH) in patients with chronic kidney disease is TRUE?
Correct Answer
A. The first-generation intact PTH assay measures both 1-84 and 7-84 moieties of PTH.
Explanation
The first-generation intact PTH assay measures both 1-84 and 7-84 moieties of PTH. This means that the assay is capable of detecting and quantifying both forms of PTH, which is important in patients with chronic kidney disease as they may have abnormalities in the production and metabolism of PTH. This information can help in assessing the overall PTH status in these patients and guide treatment decisions.
5.
It is recommend to monitor serum levels of calcium, phosphorus, PTH, and alkaline phosphatase activity beginning in CKD
Correct Answer
C. Stage 3
Explanation
The recommendation to monitor serum levels of calcium, phosphorus, PTH, and alkaline phosphatase activity beginning in stage 3 of CKD is based on the progression of the disease. In stage 3, the kidneys are moderately damaged and are not able to effectively regulate the balance of these substances in the blood. Monitoring these levels helps to assess kidney function and detect any abnormalities that may require intervention or treatment. Additionally, these tests provide valuable information about bone health and the risk of developing complications associated with CKD.
6.
In CKD stage 5, including 5D, it is recommended to monitor PTH level every:
Correct Answer
B. 3-6 months
Explanation
In CKD stage 5, including 5D, it is recommended to monitor PTH levels every 3-6 months. This is because CKD stage 5, also known as end-stage renal disease (ESRD), is characterized by severe kidney damage and significant decline in kidney function. Monitoring PTH levels is important in this stage as it helps evaluate the functioning of the parathyroid glands, which regulate calcium and phosphorus levels in the body. Regular monitoring of PTH levels every 3-6 months allows healthcare professionals to assess and manage any abnormalities or imbalances in these levels, ensuring appropriate treatment and management of the condition.
7.
In patients with CKD stages 3–5D, we recommend that therapeutic decisions be based on a single laboratory value rather than on trends, taking into account all available CKD–MBD assessments
Correct Answer
B. False
Explanation
The statement suggests that in patients with CKD stages 3-5D, therapeutic decisions should be based on a single laboratory value rather than on trends. However, the correct answer is false. The recommendation is actually to take into account all available CKD-MBD assessments when making therapeutic decisions in these patients. This means that multiple laboratory values and trends should be considered, rather than relying solely on a single value.
8.
In patients with CKD stages 3–5D with evidence of CKD–MBD, BMD testing better not to be performed routinely, because BMD does not predict fracture risk as it does in the general population, and BMD does not predict the type of renal osteodystrophy
Correct Answer
A. True
Explanation
The explanation for the given correct answer is that in patients with CKD stages 3-5D with evidence of CKD-MBD, BMD testing should not be performed routinely because BMD (bone mineral density) does not predict fracture risk as it does in the general population. Additionally, BMD does not predict the type of renal osteodystrophy. Therefore, routine BMD testing is not recommended in this specific patient population.
9.
In patients with CKD stage 5D, recommended KDIOG dialysate calcium concentration between
Correct Answer
B. 1.25 and 1.50 mmol/l
Explanation
In patients with CKD stage 5D, a recommended KDIGO dialysate calcium concentration between 1.25 and 1.50 mmol/l is suggested. This range is considered optimal for maintaining calcium balance in these patients undergoing dialysis. It helps to prevent both hypo- and hypercalcemia, which can have adverse effects on bone health and cardiovascular health. This concentration range ensures that the dialysate calcium level is within a safe and effective range for patients with CKD stage 5D.