Which grade of renal injury involves a deep laceration into the collecting system?

Correct Answer: D

Rationale: Grade 4 renal injury includes deep laceration to the collecting system urine leak (e.g., pelvis breach), per AAST scale. Grade 1 is contusion superficial. Grade 2 is <1 cm laceration no collecting system. Grade 3 is >1 cm parenchyma only. Grade 4's depth distinguishes it, critical for trauma staging, unlike lesser grades.

Correct Answer: D

Rationale: Cimetidine doesn't falsely cause hematuria beetroot, raspberries, rhubarb mimic blood (pigments), common confounders. Cimetidine (H2-blocker) lacks urinary discoloration true negative. Non-false status distinguishes it, critical for hematuria evaluation, unlike dietary mimics.

Correct Answer: C

Rationale: Ice-water enema isn't appropriate for priapism no evidence, ineffective vs. ischemic (e.g., sickle cell). Terbutaline (β-agonist), aspiration (decompression), and Neo-Synephrine (vasoconstriction) target corpora standard. Lack of efficacy distinguishes enema, key to priapism management, unlike proven interventions.

Correct Answer: C

Rationale: Vascular surgeon consult is most appropriate for a clotted dialysis shunt thrombectomy/revision restores access, standard. Heparin irrigation risks embolization unsafe. Angiogram diagnoses not treatment. Systemic urokinase is outdated local preferred if thrombolysis needed. Surgical expertise distinguishes it, key to shunt salvage, unlike irrigation or systemic options.

Correct Answer: C

Rationale: Juxtamedullary nephrons (15-20%) have large glomeruli near the cortex-medulla junction and long loops with vasa recta not 80%, surface glomeruli, or peritubular capillaries. This distinguishes their role in urine concentration, critical for medullary gradient, contrasting with cortical nephrons.