Free Certified Nephrology Nurse practice test: are you ready?

5 sample Certified Nephrology Nurse questions, explained

From the practice tests in our guide. Try them before you open the answer.

1. 1. A 48-year-old man has uncontrolled hypertension and muscle cramps. Blood tests reveal serum potassium 2.7 mEq/L, serum bicarbonate 32 mEq/L, and metabolic alkalosis. Plasma renin activity is suppressed and plasma aldosterone is elevated. Which set of findings does this condition characteristically produce?

   • A. Sodium retention, potassium wasting, and metabolic alkalosis
   • B. Sodium retention, potassium retention, and metabolic alkalosis
   • C. Sodium wasting, potassium wasting, and metabolic acidosis
   • D. Sodium wasting, potassium retention, and metabolic acidosis
   Show the answer

   Correct: A (Sodium retention, potassium wasting, and metabolic alkalosis).

   Primary hyperaldosteronism is caused by excess aldosterone, which upregulates ENaC and Na/K-ATPase. This produces sodium retention (hypertension), potassium wasting (hypokalemia), and increased hydrogen secretion (metabolic alkalosis).

   Topic: Renal Anatomy and Diagnostic Evaluation, Nephron Function, Clearance, and Test Interpretation

2. 2. For an 82-year-old patient with type 2 diabetes, CKD with eGFR 52 mL/min per 1.73 m², UACR 65 mg/g, frailty, coronary artery disease, and a history of severe hypoglycemia, which A1c target is safest and most appropriate?

   • A. below 6.0 percent
   • B. 7.5 to 8.0 percent
   • C. 6.5 to 7.0 percent
   • D. above 9.0 percent
   Show the answer

   Correct: B (7.5 to 8.0 percent).

   For older patients with frailty, cardiovascular disease, or hypoglycemia history, an A1c of 7.5 to 8.0 percent is safer than intensive control. A lower target would increase the risk of hypoglycemia without providing additional renal benefit.

   Topic: Chronic Kidney Disease Mechanisms and Complications, From Primary Causes to Staging

3. 3. Approximately 30 percent of neonates with autosomal recessive polycystic kidney disease die in the neonatal period. Which cause accounts for most of these deaths?

   • A. Respiratory insufficiency from pulmonary hypoplasia caused by oligohydramnios
   • B. Bilateral renal dysplasia
   • C. Congenital hepatic fibrosis with portal hypertension
   • D. Intracranial hemorrhage from severe hypertension
   Show the answer

   Correct: A (Respiratory insufficiency from pulmonary hypoplasia caused by oligohydramnios).

   In ARPKD, oligohydramnios from poor fetal urine output causes pulmonary hypoplasia, leading to respiratory insufficiency and neonatal death in about 30 percent of affected neonates. Hepatic fibrosis is associated with ARPKD but is not the main cause of neonatal death.

   Topic: Kidney Disease Across the Life Span, Pediatric, Pregnancy, Geriatric, and Conservative Care

4. 4. Which urine sodium value is most characteristic of acute tubular necrosis in a patient with AKI after prolonged hypotension?

   • A. 18 mEq/L
   • B. 15 mEq/L
   • C. 55 mEq/L
   • D. 8 mEq/L
   Show the answer

   Correct: C (55 mEq/L).

   In ATN, damaged tubules cannot reabsorb filtered sodium efficiently, so urine sodium is usually above 40 mEq/L. Values below 20 mEq/L are the pattern of prerenal AKI.

   Topic: Acute Kidney Injury and Inpatient Care, Detection, Prevention, and Non-Dialysis Management

5. 5. A 72 kg patient on CRRT has a net ultrafiltration rate of 150 mL/hour. The blood pressure falls from 98 to 82 mmHg, while access pressure, venous pressure, and transmembrane pressure remain normal. What is the most appropriate first response?

   • A. Increase the dialysate flow rate to maintain solute clearance without changing ultrafiltration
   • B. Increase the net ultrafiltration rate to 250 mL/hour to avoid prolonging the treatment
   • C. Stop the circuit and arrange for intermittent hemodialysis later in the day
   • D. Reduce the net ultrafiltration rate to 80 mL/hour and reassess the blood pressure
   Show the answer

   Correct: D (Reduce the net ultrafiltration rate to 80 mL/hour and reassess the blood pressure).

   Normal circuit pressures indicate that hypotension is not caused by filter or access clotting, so the ultrafiltration rate should be reduced. Lowering net ultrafiltration to 80 mL/hour is within the usual CRRT range and is the appropriate first step; continuing or increasing ultrafiltration would worsen hypotension.

   Topic: Acute Renal Replacement Therapy, Intermittent Hemodialysis, CRRT, and Inpatient Vascular Access

Frequently asked questions

Is this Certified Nephrology Nurse practice test free?

Yes. It is free, it needs no account, and you see your result immediately.

How is the readiness verdict calculated?

80% or more correct = ready, 65-79% = almost, below 65% = not yet. It is a conservative bar for practice, not the official passing score of the exam.

Where do the questions come from?

From the practice tests in our Certified Nephrology Nurse study guide, mixed across every topic of the exam: 25 questions per attempt. The sample questions on this page are not repeated in the test.