Hematology, and Immunology – 150 Practice Questions with Multiple Correct Answers, Rationales, and
Clinical Pearls.
Renal & Urinary System (1–25) – Version 3
1. Which findings are characteristic of prerenal azotemia? (Select all that apply)
A) BUN:creatinine ratio >20:1
B) Fractional excretion of sodium (FENa) <1%
C) Urine osmolality >500 mOsm/kg
D) Urine sodium <20 mEq/L
E) Muddy brown granular casts
Correct Answers: A, B, C, D
Explanation: Prerenal azotemia (decreased renal perfusion) shows elevated BUN:Cr, low FENa,
concentrated urine, low urine sodium. Muddy brown casts suggest ATN.
2. Which are risk factors for uric acid kidney stones? (Select all that apply)
A) Acidic urine pH <5.5
B) Hyperuricosuria (gout, tumor lysis)
C) High purine diet (red meat, shellfish)
D) Chronic diarrhea (low urine volume, acidic pH)
E) Alkaline urine pH >7.0
Correct Answers: A, B, C, D
Explanation: Uric acid stones form in acidic urine (pH <5.5) with high uric acid. Alkaline urine (pH >6.5)
dissolves uric acid stones.
3. Which clinical findings suggest renal papillary necrosis? (Select all that apply)
A) Sickle cell disease or trait
B) Chronic analgesic use (phenacetin, NSAIDs)
C) Diabetes mellitus
D) Gross hematuria with passage of papillary tissue
E) Pyelonephritis with sloughed papillae on imaging
Correct Answers: A, B, C, D, E
Explanation: Renal papillary necrosis causes: sickle cell (ischemia), analgesics (NSAIDs, phenacetin),
diabetes, urinary obstruction. Clues: gross hematuria, flank pain, sloughed papillae in urine/CT.
4. Which are indications for renal replacement therapy (RRT) in AKI? (Select all that apply)
A) Severe metabolic acidosis (pH <7.1)
B) Refractory hyperkalemia (K+ >6.5 with ECG changes)
C) Uremic pericarditis or encephalopathy
D) Fluid overload unresponsive to diuretics (pulmonary edema)
E) Asymptomatic creatinine rise to 3.0 mg/dL
,Correct Answers: A, B, C, D
Explanation: RRT indicated for "AEIOU": Acidosis, Electrolytes (hyperkalemia), Intoxication (dialyzable
drug), Overload (volume), Uremia (symptoms). Not for creatinine level alone.
5. Which are causes of intrinsic (intrarenal) AKI? (Select all that apply)
A) Acute tubular necrosis (ischemic or nephrotoxic)
B) Acute interstitial nephritis (drugs, infection)
C) Glomerulonephritis (post-streptococcal, lupus)
D) Renal artery stenosis
E) Bilateral ureteral obstruction
Correct Answers: A, B, C
Explanation: Intrinsic AKI involves kidney parenchyma (ATN, AIN, GN). Prerenal (renal artery stenosis)
and postrenal (obstruction) are extrinsic.
6. Which medications are nephrotoxic and can cause acute tubular necrosis (ATN)? (Select all that
apply)
A) Aminoglycosides (gentamicin, tobramycin)
B) Amphotericin B
C) Radiocontrast dye
D) Vancomycin (usually interstitial nephritis)
E) Cisplatin
Correct Answers: A, B, C, D, E
Explanation: Nephrotoxic ATN: aminoglycosides, amphotericin B, contrast, cisplatin, vancomycin (also
AIN), tenofovir, ifosfamide.
7. Which are findings in medullary cystic kidney disease (MCKD)? (Select all that apply)
A) Autosomal dominant inheritance
B) Cysts at corticomedullary junction
C) Progressive CKD with small kidneys
D) Salt wasting (hypovolemia, hyperuricemia)
E) Presents in childhood
Correct Answers: A, B, C, D
Explanation: MCKD (adult-onset, autosomal dominant): small medullary cysts, salt wasting,
hyperuricemia, gout, progressive CKD (ESRD by age 50-70). Not childhood onset (vs.
nephronophthisis).
8. Which are causes of nephrogenic diabetes insipidus (NDI)? (Select all that apply)
A) Lithium (most common drug cause)
B) Hypercalcemia
C) Hypokalemia
D) Amiloride (used to treat lithium-induced NDI)
E) X-linked (AVPR2 mutation) – congenital NDI
Correct Answers: A, B, C, D, E
Explanation: NDI (ADH resistance): lithium, hypercalcemia, hypokalemia, obstructive uropathy, genetic
,(AVPR2 or AQP2 mutations). Amiloride blocks lithium entry into collecting duct.
9. Which are findings in renal infarction (acute renal artery embolism)? (Select all that apply)
A) Sudden onset flank pain
B) Elevated LDH and alkaline phosphatase
C) Hematuria (microscopic or gross)
D) Wedge-shaped hypoenhancing area on CT
E) History of atrial fibrillation or valvular disease
Correct Answers: A, B, C, D, E
Explanation: Renal infarction: embolic (AF, endocarditis, aortic plaque), flank pain, elevated LDH/ALP
(not AST/ALT), hematuria, CT shows wedge infarct.
10. Which are causes of hypokalemia in renal disease? (Select all that apply)
A) Renal tubular acidosis (type 1 or 2) – distal and proximal RTA
B) Diuretics (thiazides, loop diuretics)
C) Bartter syndrome (loop defect, hyperreninemia)
D) Gitelman syndrome (thiazide-like defect, hypomagnesemia)
E) Type 4 RTA (hypoaldosteronism)
Correct Answers: A, B, C, D
Explanation: Hypokalemia (renal K+ wasting): RTA type 1/2, diuretics, Bartter, Gitelman, amphotericin
B, hyperaldosteronism. Type 4 RTA causes hyperkalemia.
11. Which are causes of hyperkalemia in renal disease? (Select all that apply)
A) Type 4 renal tubular acidosis (hypoaldosteronism)
B) ACE inhibitors or ARBs
C) Potassium-sparing diuretics (spironolactone, amiloride)
D) Heparin (suppresses aldosterone)
E) NSAIDs (hyporeninemic hypoaldosteronism)
Correct Answers: A, B, C, D, E
Explanation: Hyperkalemia causes: type 4 RTA (diabetes, interstitial nephritis), drugs (ACEi, ARB, K+-
sparing diuretics, heparin, NSAIDs, TMP-SMX, calcineurin inhibitors).
12. Which are findings in acute phosphate nephropathy? (Select all that apply)
A) Associated with oral sodium phosphate bowel prep (colonoscopy)
B) Acute kidney injury within hours to days
C) Tubular deposition of calcium-phosphate crystals
D) Hypocalcemia (due to precipitation)
E) Complete recovery in all cases
Correct Answers: A, B, C, D
Explanation: Acute phosphate nephropathy (oral sodium phosphate, especially in elderly, CKD, ACEi
users): AKI, crystal deposition, hypocalcemia. Often not fully reversible.
13. Which are causes of CKD that are potentially reversible if treated early? (Select all that apply)
A) Obstructive uropathy (BPH, stone)
, B) Renovascular disease (renal artery stenosis)
C) Multiple myeloma (cast nephropathy)
D) Diabetic nephropathy
E) Chronic glomerulonephritis
Correct Answers: A, B, C
Explanation: Potentially reversible CKD causes: obstruction, renovascular, myeloma, hypercalcemia,
drug toxicity (lithium, NSAIDs), interstitial nephritis. Diabetic nephropathy and chronic GN are
irreversible.
14. Which are findings in hepatorenal syndrome (HRS) versus acute tubular necrosis (ATN) in
cirrhosis? (Select all that apply)
A) HRS: low FENa (<0.1-0.2%)
B) ATN: FENa >2%
C) HRS: bland urine sediment
D) ATN: granular casts
E) HRS: response to albumin plus vasoconstrictors
Correct Answers: A, B, C, D, E
Explanation: HRS (prerenal physiology in cirrhosis): low FENa, bland sediment, responds to
vasoconstrictors + albumin. ATN: high FENa, granular casts, no response.
15. Which are causes of amyloidosis affecting the kidney? (Select all that apply)
A) AL (primary) amyloidosis (light chains, multiple myeloma)
B) AA (secondary) amyloidosis (chronic inflammation: RA, IBD, osteomyelitis)
C) Familial (transthyretin, fibrinogen)
D) Dialysis-related (beta-2 microglobulin)
E) Diabetes mellitus
Correct Answers: A, B, C, D
Explanation: Renal amyloidosis: AL (most common), AA (chronic inflammation), hereditary (TTR,
apolipoprotein), dialysis-related (β2-microglobulin). Diabetes causes diabetic nephropathy, not
amyloid.
16. Which are findings in renal amyloidosis? (Select all that apply)
A) Nephrotic syndrome (heavy proteinuria)
B) Progressive CKD
C) Congo red stain positive with apple-green birefringence
D) Enlarged kidneys (early), small kidneys (late)
E) Normal kidney size
Correct Answers: A, B, C, D
Explanation: Renal amyloid: nephrotic range proteinuria (often >5-10 g/day), CKD progression, Congo
red positive, kidneys normal or enlarged early, small late (unlike other CKD).
17. Which are causes of thin basement membrane disease (benign familial hematuria)? (Select all
that apply)
A) COL4A3 or COL4A4 mutations (heterozygous)