Nephrology and Hypertension Flashcards

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?

Answer: Sparsentan

Sparsentan, a dual endothelin-angiotensin receptor antagonist, has demonstrated significant proteinuria reduction and renal protective effects in IgA nephropathy.

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?

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.

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?

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.

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?

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.

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?

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.

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?

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.

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?

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.

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?

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.

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?

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.

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?

Answer: Fanconi syndrome

Tenofovir disoproxil fumarate can cause mitochondrial toxicity in proximal tubular cells, leading to Fanconi syndrome with global proximal tubule dysfunction.

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?

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.

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?

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.

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?

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.

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?

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.