How can I create 20 multiple-choice questions on renal regulation of electrolytes and fluid volume control based on Guyton physiology?

20 Multiple Choice Questions on Renal Regulation of Electrolytes and Fluid Volume Control

I will create 20 high-quality MCQs on renal physiology based on Guyton principles, focusing on electrolyte and fluid volume regulation.

Potassium Regulation MCQs

1. Which nephron segment is primarily responsible for potassium secretion? A) Proximal tubule B) Thin descending limb C) Thick ascending limb D) Distal convoluted tubule and collecting duct

   Answer: D) Distal convoluted tubule and collecting duct 1

2. Hypokalemia during continuous kidney replacement therapy (CKRT) is most effectively prevented by: A) Oral potassium supplements B) Using dialysate solutions with potassium concentration of 4 mEq/L C) Intravenous potassium supplementation D) Reducing dialysis time

   Answer: B) Using dialysate solutions with potassium concentration of 4 mEq/L 1, 2

3. Which of the following is the major intracellular cation? A) Sodium B) Potassium C) Calcium D) Magnesium

   Answer: B) Potassium 1

4. The Na/K-ATPase activity that maintains intracellular potassium concentration can be impaired by: A) Excess dietary potassium B) Insufficient supplies of oxygen and energy C) Hyperkalemia D) Increased aldosterone

   Answer: B) Insufficient supplies of oxygen and energy 1

Calcium Regulation MCQs

1. What percentage of filtered calcium is reabsorbed in the proximal tubules? A) 20% B) 40% C) 60% D) 80%

   Answer: C) 60% 3

2. Which protein in the thick ascending limb is responsible for paracellular calcium reabsorption? A) TRPV5 B) Calbindin-D28K C) Paracellin-1 (claudin-16) D) Calcium sensing receptor (CaSR)

   Answer: C) Paracellin-1 (claudin-16) 3

3. In the distal convoluted tubule, which protein serves as the main portal of entry for calcium reabsorption? A) NCX1 B) TRPV5 C) Plasma membrane Ca²⁺-ATPase D) Calbindin-D28K

   Answer: B) TRPV5 3

4. What is the normal plasma calcium concentration range? A) 6.5-8.5 mg/dL B) 8.5-10.5 mg/dL C) 10.5-12.5 mg/dL D) 12.5-14.5 mg/dL

   Answer: B) 8.5-10.5 mg/dL 4

Phosphate Regulation MCQs

1. What is the target serum phosphate level that should be maintained in acutely ill patients? A) >0.61 mmol/L B) >0.71 mmol/L C) >0.81 mmol/L D) >0.91 mmol/L

   Answer: C) >0.81 mmol/L 1

2. In patients with hypophosphatemia receiving continuous kidney replacement therapy, the preferred approach is: A) Intravenous phosphate supplementation B) Oral phosphate supplements C) Using dialysis solutions containing phosphate D) Reducing dialysis time

   Answer: C) Using dialysis solutions containing phosphate 1, 2

3. Phosphate deficiency can lead to: A) Decreased urinary magnesium excretion B) Increased urinary magnesium and calcium excretion C) Decreased urinary calcium excretion D) No effect on other electrolyte excretion

   Answer: B) Increased urinary magnesium and calcium excretion 4

4. In the theoretical model for phosphorus requirements in parenteral nutrition, which formula is used? A) P requirement = [calcium deposition/1.67] + [protein accretion0.33] B) P requirement = [calcium deposition1.67] + [protein accretion0.33] C) P requirement = [calcium deposition/1.67] - [protein accretion0.33] D) P requirement = [calcium deposition1.67] - [protein accretion0.33]

   Answer: A) P requirement = [calcium deposition/1.67] + [protein accretion*0.33] 1

Magnesium Regulation MCQs

1. What percentage of filtered magnesium is reabsorbed in the thick ascending limb of the loop of Henle? A) 20-30% B) 30-40% C) 50-60% D) 70-80%

   Answer: C) 50-60% 3

2. The target serum magnesium concentration that should be maintained in acutely ill patients is: A) ≥0.50 mmol/L B) ≥0.60 mmol/L C) ≥0.70 mmol/L D) ≥0.80 mmol/L

   Answer: C) ≥0.70 mmol/L 1

3. Which of the following increases the risk of hypomagnesemia during continuous kidney replacement therapy? A) Using high magnesium concentration dialysate B) Regional citrate anticoagulation C) Reducing dialysis time D) Using phosphate-containing solutions

   Answer: B) Regional citrate anticoagulation 1, 2

4. Magnesium reabsorption in the ascending limb of the loop of Henle is primarily: A) Active and transcellular B) Passive and paracellular C) Active and paracellular D) Passive and transcellular

   Answer: B) Passive and paracellular 3

Integration of Renal Mechanisms for Blood Volume and ECF Volume Control MCQs

1. Which of the following is NOT a strategy to manage hypertension in hemodialysis patients? A) Probing the prescribed target weight B) Increasing treatment time and/or frequency C) Decreasing interdialytic weight gain D) Increasing sodium intake

   Answer: D) Increasing sodium intake 2

2. In peritoneal dialysis patients, which of the following strategies can help maximize ultrafiltration for long dwells? A) Using lower tonicity glucose-based solutions B) Using icodextrin for long dwells C) Increasing dietary salt D) Avoiding diuretics in those with residual kidney function

   Answer: B) Using icodextrin for long dwells 2

3. The "strong ion difference" (SID) is an important concept in acid-base balance that involves which primary ions? A) Potassium and magnesium B) Calcium and phosphate C) Sodium and chloride D) Bicarbonate and hydrogen

   Answer: C) Sodium and chloride 1, 5

4. In patients at risk of increased endogenous secretion of ADH, maintenance fluid therapy volume should be restricted to what percentage of the volume calculated by the Holliday and Segar formula? A) 40-55% B) 55-65% C) 65-80% D) 80-95%

   Answer: C) 65-80% 1