ITE Nephrology and Hypertension — Questions and Answers
Question 1: A 55-year-old woman with IgA nephropathy has a urine protein-to-creatinine ratio of 1.8 g/g and eGFR of 52 mL/min/1.73m². Which additional therapy beyond RAS blockade has demonstrated benefit in slowing CKD progression in this condition?
- Hydroxychloroquine
- Sparsentan (Correct answer)
- Mycophenolate mofetil
- Rituximab
Correct answer: Sparsentan
Sparsentan, a dual endothelin-angiotensin receptor antagonist, has demonstrated significant proteinuria reduction and renal protective effects in IgA nephropathy.
Question 2: A 40-year-old man presents with hematuria, flank pain, and a palpable abdominal mass. Imaging shows bilateral enlarged kidneys with multiple cysts. His father had the same condition and died from a ruptured intracranial aneurysm. Which gene mutation is most likely responsible?
- PKD2
- PKD1 (Correct answer)
- TSC1
- VHL
Correct answer: PKD1
PKD1 mutations account for approximately 85% of autosomal dominant polycystic kidney disease cases and are associated with more severe disease and earlier ESRD.
Question 3: A 30-year-old pregnant woman at 32 weeks develops BP of 158/102 mmHg, 3+ proteinuria, and a platelet count of 82,000/µL with elevated LDH. What is the most appropriate next step?
- IV labetalol and expectant management until 37 weeks
- Emergent delivery after maternal stabilization (Correct answer)
- Oral nifedipine and close outpatient monitoring
- IV magnesium only and recheck labs in 24 hours
Correct answer: Emergent delivery after maternal stabilization
HELLP syndrome (hemolysis, elevated liver enzymes, low platelets) at ≥32 weeks warrants delivery after maternal stabilization with magnesium and antihypertensives.
Question 4: A patient with nephrotic syndrome develops sudden flank pain and gross hematuria. Doppler ultrasound reveals absent flow in the left renal vein. Which underlying condition most predisposes to this complication?
- Focal segmental glomerulosclerosis
- Membranous nephropathy (Correct answer)
- Minimal change disease
- IgA nephropathy
Correct answer: Membranous nephropathy
Membranous nephropathy carries the highest risk of renal vein thrombosis among nephrotic syndromes due to urinary loss of anticoagulant proteins like protein C, S, and antithrombin III.
Question 5: A 62-year-old man with type 2 diabetes and CKD stage 3b (eGFR 38) is on maximally tolerated ACEI. His most recent urine albumin-to-creatinine ratio is 420 mg/g. Which agent should be added to further reduce cardiorenal risk?
- Amlodipine
- Spironolactone
- Finerenone (Correct answer)
- Hydralazine
Correct answer: Finerenone
Finerenone, a non-steroidal mineralocorticoid receptor antagonist, has demonstrated reduction in CKD progression and cardiovascular events in diabetic CKD when added to RAS blockade.
Question 6: A 45-year-old man presents with acute oliguric kidney injury, hemoptysis, and pANCA positivity. Kidney biopsy shows pauci-immune crescentic glomerulonephritis. What is the most appropriate induction therapy?
- Rituximab alone
- High-dose glucocorticoids plus cyclophosphamide or rituximab (Correct answer)
- Mycophenolate mofetil plus prednisone
- Plasmapheresis alone
Correct answer: High-dose glucocorticoids plus cyclophosphamide or rituximab
ANCA-associated vasculitis with rapidly progressive GN requires induction with high-dose glucocorticoids combined with either cyclophosphamide or rituximab.
Question 7: A 70-year-old man with hypertension, CKD stage 3 (eGFR 42), and recent MI is found to have serum potassium of 5.9 mEq/L on lisinopril and spironolactone. What is the most appropriate management?
- Discontinue lisinopril and continue spironolactone
- Discontinue spironolactone and continue lisinopril
- Add patiromer and continue both medications (Correct answer)
- Switch to hydralazine and isosorbide dinitrate
Correct answer: Add patiromer and continue both medications
Patiromer (or sodium zirconium cyclosilicate) can lower serum potassium sufficiently to allow continuation of both cardiorenal protective agents in patients with hyperkalemia.
Question 8: A 25-year-old woman is found to have BP of 170/100 mmHg on routine exam. Labs show hypokalemia, suppressed plasma renin activity, and elevated aldosterone. CT shows no adrenal mass. What is the best next diagnostic step?
- Renal artery Doppler ultrasound
- Adrenal vein sampling (Correct answer)
- 24-hour urine metanephrines
- MRI of the pituitary
Correct answer: Adrenal vein sampling
Adrenal vein sampling is the gold standard for differentiating unilateral aldosterone-producing adenoma from bilateral adrenal hyperplasia when CT is non-diagnostic.
Question 9: A 58-year-old man on hemodialysis for 8 years presents with bone pain and a serum calcium of 11.2 mg/dL, phosphorus of 5.8 mg/dL, and intact PTH of 850 pg/mL. What is this condition called and what surgical intervention may be needed?
- Secondary hyperparathyroidism; parathyroidectomy if refractory to cinacalcet
- Tertiary hyperparathyroidism; parathyroidectomy if refractory to cinacalcet (Correct answer)
- Adynamic bone disease; bisphosphonate therapy
- Primary hyperparathyroidism; single-gland parathyroidectomy
Correct answer: Tertiary hyperparathyroidism; parathyroidectomy if refractory to cinacalcet
Tertiary hyperparathyroidism occurs in long-term dialysis patients when autonomous PTH hypersecretion persists and may require parathyroidectomy if calcimimetics fail.
Question 10: A 48-year-old HIV-positive man on tenofovir disoproxil fumarate presents with a proximal renal tubular acidosis, glucosuria with normal serum glucose, hypophosphatemia, and hypokalemia. What syndrome does this represent?
- Bartter syndrome
- Gitelman syndrome
- Fanconi syndrome (Correct answer)
- Type 4 renal tubular acidosis
Correct answer: Fanconi syndrome
Tenofovir disoproxil fumarate can cause mitochondrial toxicity in proximal tubular cells, leading to Fanconi syndrome with global proximal tubule dysfunction.
Question 11: A 35-year-old woman with lupus nephritis class IV on mycophenolate and prednisone has a serum creatinine rise from 1.1 to 2.4 mg/dL over 3 months with worsening proteinuria. What is the best next step?
- Add hydroxychloroquine
- Switch mycophenolate to cyclophosphamide
- Repeat kidney biopsy (Correct answer)
- Add belimumab
Correct answer: Repeat kidney biopsy
A repeat kidney biopsy in lupus nephritis is essential to determine whether the class has transformed, activity has increased, or chronic scarring has developed before changing therapy.
Question 12: A 66-year-old man with hypertension is started on chlorthalidone. Two weeks later he reports muscle cramps. Labs: Na 138 mEq/L, K 3.0 mEq/L, Cl 94 mEq/L, HCO3 29 mEq/L, urine Cl 60 mEq/L. What acid-base disorder is present?
- Metabolic acidosis with respiratory compensation
- Metabolic alkalosis with appropriate respiratory compensation (Correct answer)
- Respiratory alkalosis with renal compensation
- Mixed metabolic alkalosis and respiratory alkalosis
Correct answer: Metabolic alkalosis with appropriate respiratory compensation
Thiazide diuretics cause metabolic alkalosis via volume contraction, increased aldosterone, and direct H+ and K+ loss in the collecting duct.
Question 13: A 72-year-old woman with stage 4 CKD is found to have serum bicarbonate of 18 mEq/L. Which intervention has been shown to slow CKD progression in addition to correcting the acidosis?
- Sodium bicarbonate supplementation (Correct answer)
- Dietary protein restriction alone
- Furosemide to reduce sodium load
- Calcium carbonate as a phosphate binder
Correct answer: Sodium bicarbonate supplementation
Alkali therapy with oral sodium bicarbonate has been shown in multiple trials to slow GFR decline in CKD patients with metabolic acidosis.
Question 14: A 29-year-old man presents with painless hematuria. Urine microscopy shows dysmorphic RBCs and RBC casts. Serum complement C3 and C4 are normal. Kidney biopsy shows mesangial IgA deposits. His serum IgA level is elevated. What triggers commonly cause gross hematuria episodes in this condition?
- Streptococcal pharyngitis with a 2-3 week latency
- Concurrent upper respiratory infections (synpharyngitic hematuria) (Correct answer)
- NSAIDs use
- Vigorous exercise only
Correct answer: Concurrent upper respiratory infections (synpharyngitic hematuria)
IgA nephropathy classically causes synpharyngitic hematuria (gross hematuria coinciding with mucosal infection) in contrast to post-streptococcal GN which has a latency period.
