Detrusor overactivity can be diagnosed during urodynamics

Correct Answer: A

Rationale: Detrusor overactivity (DO) is diagnosed by involuntary contractions during filling any size, reflecting bladder instability (e.g., urge incontinence). Amplitude threshold (e.g., >15 cm Hâ‚‚O) isn't required presence matters. Cough leakage is stress incontinence, not DO different mechanism. Voiding phase contractions are normal micturition, not overactivity. Filling-phase involuntariness distinguishes DO, key to its urodynamic definition, unlike size, stress, or voiding errors.

Correct Answer: B

Rationale: PI-RADS v2.1 divides prostate into 38 sectors 36 prostate zones (base, mid, apex; anterior/posterior) plus 2 urethra standardized for MRI reporting. 27 is outdated (v1) too few. 41/43 include seminal vesicles/sphincter excluded here. 38 distinguishes it, critical for precise cancer localization, unlike old or inclusive counts.

Correct Answer: C

Rationale: Chromophobe RCC arises from intercalated cells of collecting ducts unique histology (pale cytoplasm). Proximal tubule births clear cell/papillary RCC different lineage. Both tubules isn't specific wrong scope. Principal cells manage sodium unrelated. Intercalated origin distinguishes chromophobe, key to its pathology, unlike proximal or principal sources.

Correct Answer: A

Rationale: Acute tubular necrosis (ATN) is the top cause of acute renal failure ischemia/toxins (e.g., sepsis) damage tubules, impairing filtration. Glomerulonephritis (immune) is less frequent chronic more common. Vasculitis (e.g., ANCA) is rare systemic. Tubulointerstitial nephritis (drugs) occurs but trails ATN less acute. ATN's prevalence distinguishes it, critical for ARF etiology, unlike glomerular or interstitial causes.

Correct Answer: C

Rationale: Plasma aldosterone-to-renin ratio (ARR) screens primary aldosteronism best high aldosterone, low renin (e.g., adenoma) flags it reliably. Serum potassium (hypokalemia) is suggestive non-specific. Urine aldosterone is diagnostic, not screening cumbersome. Adrenal vein sampling confirms laterality post-screening. ARR's sensitivity distinguishes it, critical for early detection, unlike secondary or invasive tests.