FREE Internal Medicine Renal and Electrolyte Imbalance Questions and Answers

Question 1

A 58-year-old male with a history of hypertension and chronic kidney disease (CKD) stage 3 presents with generalized weakness and muscle cramps.
His laboratory results show a serum potassium of 6.5 mEq/L, creatinine of 2.8 mg/dL, and BUN of 45 mg/dL.
ECG shows peaked T-waves.
Which of the following is the most appropriate initial treatment for his hyperkalemia?

Accepted Answer

Intravenous calcium gluconate

Answer

Insulin and dextrose

Answer

Sodium polystyrene sulfonate

Answer

Furosemide

Question 2

Which of the following conditions is most likely to cause a normal anion gap metabolic acidosis?

Accepted Answer

Severe diarrhea

Answer

Lactic acidosis

Answer

Diabetic ketoacidosis

Answer

Renal failure

Question 3

A 72-year-old female with a history of heart failure and CKD stage 4 (eGFR 25 mL/min/1.73m²) is admitted with altered mental status. Her sodium is 118 mEq/L. She is on a loop diuretic and has significant peripheral edema. Her urine osmolality is 400 mOsm/kg and urine sodium is 60 mEq/L. Which of the following is the most likely cause of her hyponatremia?

Accepted Answer

Hypervolemic hyponatremia due to heart failure

Answer

Syndrome of Inappropriate Antidiuretic Hormone (SIADH)

Answer

Primary polydipsia

Answer

Hypothyroidism

Question 4

Regarding the management of acute kidney injury (AKI), which of the following statements is most accurate?

Accepted Answer

Contrast-induced nephropathy is best prevented by aggressive hydration with normal saline prior to contrast exposure in high-risk patients.

Answer

Fluid restriction is the primary intervention for prerenal AKI.

Answer

Discontinuation of nephrotoxic medications is crucial in all forms of AKI.

Answer

Urgent dialysis is indicated for all patients with AKI and hyperkalemia.

Question 5

A 65-year-old male with a history of prostate cancer with bone metastases presents with polyuria, polydipsia, and fatigue. Laboratory tests reveal a serum calcium of 13.5 mg/dL (normal 8.5-10.2 mg/dL) and an intact PTH level of 10 pg/mL (normal 15-65 pg/mL). His phosphorus is 2.0 mg/dL (normal 2.5-4.5 mg/dL). Which of the following is the most appropriate initial step in managing his hypercalcemia?

Accepted Answer

Administer intravenous normal saline

Answer

Initiate cinacalcet

Answer

Order a parathyroidectomy

Answer

Start calcitriol supplementation

Question 6

A 40-year-old male presents with recurrent nephrolithiasis. Analysis of a passed stone reveals calcium oxalate. His 24-hour urine collection shows hypercalciuria (350 mg/day, normal <250 mg/day). Serum calcium and PTH levels are normal. Which of the following dietary recommendations would be most beneficial in preventing future stone formation?

Accepted Answer

Increase fluid intake to achieve a urine volume >2.5 L/day

Answer

Restrict dietary calcium intake

Answer

Increase intake of oxalate-rich foods

Answer

Restrict dietary sodium intake to <2 grams/day