Urologic Surgery

111 questions

All types111 Multiple choice57 Matching28 Ordering26

Match each clinical presentation to its most appropriate definitive surgical procedure.

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Answer

BPH refractory to medical therapy is treated with TURP. Testicular torsion requires immediate surgical exploration and bilateral orchiopexy. Muscle-invasive bladder cancer is treated with radical cystectomy and urinary diversion. A solid testicular mass requires a radical inguinal orchiectomy.

Each clinical scenario requires a highly specific, standard-of-care surgical intervention. BPH refractory to medical therapy necessitates procedures like TURP. Testicular torsion is a surgical emergency requiring exploration and bilateral orchiopexy. Muscle-invasive bladder cancer requires radical cystectomy. Finally, a suspicious testicular mass is managed with a radical inguinal orchiectomy to prevent tumor seeding.

Step-by-Step Solution

Analyze each clinical presentation to determine the underlying urologic diagnosis.

The diagnoses are: medically refractory BPH, testicular torsion, muscle-invasive bladder cancer, and suspected testicular cancer.

Accurate diagnosis is required to select the correct definitive surgical management.

Select the standard-of-care surgical procedure for each diagnosis.

BPH is matched to TURP; Torsion is matched to Exploration & Orchiopexy; Bladder Cancer is matched to Radical Cystectomy; Testicular Mass is matched to Radical Inguinal Orchiectomy.

These represent the fundamental surgical treatments for these core urologic conditions.

Key Concept

Indications for core urologic surgical procedures

Question 22Question →

Match each of the following clinical presentations with the most appropriate definitive surgical or interventional next step in management.

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Answer

Each urologic emergency or oncology scenario must be paired with its standard-of-care surgical intervention, prioritizing organ preservation where safe, and aggressive extirpation where oncologically necessary.

The correct matches align distinct urologic pathologies with their gold-standard surgical interventions. Testicular torsion requires immediate restoration of blood flow and bilateral orchiopexy to prevent future occurrences. An infected, obstructing ureteral stone leading to sepsis is a surgical emergency demanding urgent decompression of the collecting system, rather than definitive stone fragmentation. For a small, localized renal mass, a partial nephrectomy is indicated to preserve renal function while ensuring oncologic efficacy. Muscle-invasive bladder cancer necessitates definitive extirpation via radical cystectomy and urinary diversion. Finally, a highly suspicious solid testicular mass requires a radical inguinal orchiectomy.

Step-by-Step Solution

Evaluate the patient with an acute scrotum lacking arterial flow.

Diagnose testicular torsion.

Requires emergent surgical unwinding and bilateral orchiopexy to prevent necrosis.

Analyze the case of an obstructing ureteral stone accompanied by fever and hypotension.

Identify a urologic emergency (obstructive pyelonephritis/sepsis).

Demands immediate percutaneous or internal stent decompression prior to definitive stone treatment.

Assess the 3.5-cm isolated, exophytic renal mass.

Diagnose a Stage T1a renal cell carcinoma.

Indicates partial nephrectomy to maximize preserved functional renal parenchyma.

Evaluate the pathology showing detrusor muscle invasion in bladder cancer.

Confirm muscle-invasive disease.

Requires radical cystectomy rather than repeat transurethral resection.

Identify the solid intratesticular mass in a young adult.

Diagnose primary testicular cancer.

Necessitates a radical inguinal orchiectomy to prevent altering lymphatic drainage.

Key Concept

Definitive surgical management of core urologic pathologies

Estimated Time:2m 0s

Question 23Question →

A 68-year-old man is evaluated in the emergency department for severe left flank pain, high fever, and confusion. His medical history is significant for permanent atrial fibrillation, for which he takes apixaban. Two days ago, he visited an urgent care clinic for dysuria; a urine culture sent at that time is now growing *Escherichia coli* that is susceptible to ceftriaxone and resistant to ciprofloxacin.

On arrival, his temperature is $39.4^\circ\text{C}$ ( $102.9^\circ\text{F}$ ), blood pressure is $85/50\text{ mmHg}$ , heart rate is $125/\text{min}$ , and respiratory rate is $24/\text{min}$ . Physical examination reveals exquisite left costovertebral angle tenderness.

Laboratory studies show:

Test	Result
Leukocyte count	$22,000/\text{mm}^3$
Hemoglobin	$12.8\text{ g/dL}$
Platelet count	$210,000/\text{mm}^3$
Creatinine	$2.1\text{ mg/dL}$ (baseline $1.0\text{ mg/dL}$ )
INR	$1.1$

A bedside ultrasound demonstrates severe left hydroureteronephrosis but cannot identify the level of obstruction. The patient receives a $2\text{-L}$ intravenous fluid bolus and is started on intravenous ceftriaxone. Thirty minutes later, his blood pressure remains $88/52\text{ mmHg}$ and he is increasingly lethargic. Which of the following is the most appropriate next step in management?

Cystoscopy with retrograde ureteral stent placement

Image-guided percutaneous nephrostomy

Addition of intravenous vancomycin and switch to meropenem

Transport to radiology for a non-contrast CT scan of the abdomen and pelvis

Continued intravenous fluid resuscitation and observation

Show answer & explanation

Answer: Cystoscopy with retrograde ureteral stent placement

Answer

Cystoscopy with retrograde ureteral stent placement

This patient presents with obstructive pyelonephritis progressing to septic shock (urosepsis), which is a urologic emergency requiring immediate decompression of the infected collecting system. Bedside ultrasound confirms hydronephrosis, establishing the diagnosis. The two standard modalities for decompression are percutaneous nephrostomy (PCN) and retrograde ureteral stenting. However, this patient is actively taking apixaban, a direct oral anticoagulant. PCN requires tracting through the highly vascular renal parenchyma, which carries an unacceptably high risk of life-threatening retroperitoneal hemorrhage in a coagulopathic patient. Retrograde ureteral stenting avoids parenchymal puncture entirely and is the safest, most appropriate intervention to achieve source control.

Step-by-Step Solution

Assess the patient's hemodynamic status and clinical presentation.

The patient is in septic shock (hypotension refractory to fluids) secondary to an infected, obstructed kidney (fever, flank pain, hydronephrosis).

To recognize that this is a urologic emergency requiring immediate source control via decompression.

Evaluate the patient's medication list and coagulation status.

The patient is on apixaban, a direct oral anticoagulant (DOAC) that causes significant clinical coagulopathy despite a normal INR.

To determine the safety profile of invasive urologic procedures.

Select the safest method for collecting system decompression.

Retrograde ureteral stenting is chosen over percutaneous nephrostomy.

Stenting utilizes natural orifices and avoids puncturing the highly vascular renal parenchyma, minimizing the risk of catastrophic bleeding in an anticoagulated patient.

Key Concept

Emergent surgical decompression of obstructive urosepsis in patients on active anticoagulation.

Estimated Time:1m 30s

Question 24Question →

A $42$ -year-old man comes to the emergency department due to sudden-onset, severe left-sided flank pain that radiates to his left groin. He has no significant past medical history. His temperature is $37.1^\circ\text{C}$ ( $98.8^\circ\text{F}$ ), blood pressure is $140/90\text{ mmHg}$ , pulse is $98\text{/min}$ , and respirations are $16\text{/min}$ . Physical examination reveals left costovertebral angle tenderness but a soft, non-tender abdomen. Laboratory studies show a normal leukocyte count and urinalysis is positive for microscopic hematuria but negative for leukocyte esterase and nitrites. A noncontrast CT scan of the abdomen and pelvis reveals a $4\text{-mm}$ stone in the left distal ureter with mild hydroureter. His pain improves significantly after receiving intravenous ketorolac. Which of the following is the most appropriate next step in management?

Discharge home with tamsulosin and encourage oral fluid intake

Administration of intravenous broad-spectrum antibiotics

Extracorporeal shock wave lithotripsy

Placement of a percutaneous nephrostomy tube

Ureteroscopic stone extraction

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Answer: Discharge home with tamsulosin and encourage oral fluid intake

Answer

The correct answer is to discharge the patient home with tamsulosin and encourage oral fluid intake.

The correct answer involves discharging the patient with medical expulsive therapy. Ureteral stones less than

5\text{ mm}

in diameter have a high likelihood (often

>80\%

) of spontaneous passage. Because this patient has well-controlled pain, normal renal function, and no evidence of urinary tract infection, he does not require hospital admission or immediate urologic intervention. An alpha-1 receptor blocker, such as tamsulosin, relaxes the smooth muscle of the distal ureter, facilitating stone passage.

Step-by-Step Solution

Evaluate the patient's clinical stability and signs of infection.

The patient is afebrile with normal vital signs, normal leukocyte count, and negative urinalysis for infection.

To rule out a urologic emergency such as an infected obstructing stone, which would require immediate decompression.

Assess the stone size and location from the imaging.

The CT scan shows a

4\text{-mm}

stone in the distal ureter.

Stone size and location are the primary predictors of spontaneous passage. Stones under

5\text{ mm}

have a high probability of passing spontaneously.

Determine the appropriate management strategy based on stone characteristics and patient status.

Medical expulsive therapy (alpha-blockers and hydration) in an outpatient setting is selected.

Conservative management is indicated for small, uncomplicated stones in patients with well-controlled pain.

Key Concept

Uncomplicated ureteral stones smaller than

5\text{ mm}

in stable patients with controlled pain should be managed conservatively with a trial of spontaneous passage using medical expulsive therapy.

Question 25Question →

Match each clinical presentation of a urologic injury or surgical complication to its most appropriate definitive management or immediate next step.

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Answer

Extraperitoneal bladder rupture requires urethral Foley catheter drainage. Intraperitoneal bladder rupture requires exploratory laparotomy with primary closure. Posterior urethral injury requires suprapubic cystostomy placement. Ureterovaginal fistula requires urinary diversion via percutaneous nephrostomy. Ureteral injury with urinoma requires ureteral stent placement and percutaneous fluid drainage.

Each clinical presentation is uniquely matched to its guideline-directed surgical or conservative management based on the specific anatomical location of the injury and the timeline of the presentation.

Step-by-Step Solution

Analyze the imaging findings to classify the anatomical location of the bladder injury.

Contrast confined to the retropubic space indicates extraperitoneal rupture, whereas contrast outlining bowel loops indicates intraperitoneal rupture.

Management of bladder trauma strictly depends on the relationship of the rupture to the peritoneal reflection.

Determine the optimal initial intervention for suspected urethral injuries.

Avoid blind urethral catheterization and place a suprapubic cystostomy.

Catheterization can convert a partial urethral tear into a complete transection.

Evaluate the timeline and presentation of the iatrogenic ureteral injuries to guide surgical timing.

Recognize that a 2-week-old ureterovaginal fistula is highly inflamed, requiring diversion (nephrostomy) rather than immediate reconstruction. An infected urinoma needs active drainage alongside internal stenting.

Operating on acutely inflamed, friable tissue leads to high failure rates in reconstructive urologic surgery, and undrained collections lead to sepsis.

Key Concept

The management of urologic trauma and post-surgical complications relies on accurate anatomical diagnosis (intra- vs. extraperitoneal, anterior vs. posterior urethra) and avoiding interventions that exacerbate the injury or risk sepsis.

Question 26Question →

A 34-year-old man is brought to the emergency department after a high-speed motorcycle collision. He is hemodynamically stable, and a primary trauma survey reveals no acute intracranial, thoracic, or abdominal life-threatening injuries. Pelvic radiography demonstrates a displaced fracture of the pubic rami. On physical examination, there is prominent blood at the urethral meatus, a severely swollen and ecchymotic scrotum, and the patient reports a strong urge to void but is unable to do so. Digital rectal examination reveals a high-riding, boggy prostate. Arrange the following steps in the most appropriate chronological sequence for the standard diagnostic and surgical management of this patient's urologic injury.

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Answer

The correct chronological sequence is: 1) Perform retrograde urethrography (RUG), 2) Place a suprapubic cystostomy tube, 3) Delay further intervention for 3 to 6 months, and 4) Perform formal anastomotic urethroplasty.

The correct management sequence for a suspected posterior urethral injury in the setting of pelvic trauma requires a careful, staged approach. First, the presence of blood at the urethral meatus and a high-riding prostate strictly contraindicates blind urethral catheterization. Therefore, retrograde urethrography (RUG) must be performed to visualize the extent of the urethral disruption. Once a complete transection is confirmed, immediate urinary diversion is required, which is accomplished via the placement of a suprapubic cystostomy tube. Immediate definitive surgical repair is contraindicated because the acute pelvic hematoma and friable tissues obscure anatomical planes, making surgery extremely hazardous and highly associated with postoperative incontinence and erectile dysfunction. Instead, a delay of 3 to 6 months is observed to allow the hematoma to reabsorb and the injury to stabilize into a defined stricture. Finally, a delayed formal anastomotic urethroplasty is performed to definitively restore continuity to the urinary tract.

Step-by-Step Solution

Recognize signs of posterior urethral injury.

The patient has a pelvic fracture, blood at the urethral meatus, an inability to void, and a high-riding prostate.

These findings are highly specific for a posterior urethral disruption, typically at the membranous urethra.

Determine the initial diagnostic test.

Retrograde urethrography (RUG) must be performed first.

Blind urethral catheterization is strictly contraindicated in this setting, as it can worsen a partial tear into a complete transection.

Establish safe urinary drainage.

Placement of a suprapubic cystostomy tube.

Because the urethra is disrupted, urine must be diverted directly from the bladder through the abdominal wall to prevent urinary extravasation and relieve retention.

Plan the timeline for definitive surgical repair.

Delay surgery for 3 to 6 months, followed by an anastomotic urethroplasty.

Immediate open reconstruction carries an unacceptably high risk of severe hemorrhage, erectile dysfunction, and incontinence due to the obscured tissue planes from the acute pelvic hematoma.

Key Concept

Management of Posterior Urethral Disruption

Question 27Question →

A 26-year-old man is brought to the emergency department after a severe motor vehicle collision. Primary survey reveals an unstable pelvic fracture. Genitourinary examination shows blood at the urethral meatus, a scrotal hematoma, and a high-riding prostate on digital rectal examination. A transurethral Foley catheter has not been placed. Arrange the following steps in the most appropriate sequential order for the diagnosis and definitive management of this patient's urologic injury.

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Answer

The correct sequence is to first perform a retrograde urethrogram, followed by placing a suprapubic cystostomy tube, then allowing time for the pelvic hematoma to resolve, and finally performing a delayed formal urethroplasty.

The correct sequence strictly follows the standard of care for posterior urethral injury. First, a retrograde urethrogram (RUG) is mandatory to definitively diagnose a urethral tear, as transurethral catheterization is strictly contraindicated. Second, once the RUG demonstrates extravasation indicative of a disruption, the bladder must be drained using a suprapubic cystostomy tube. Third, the patient is discharged with the suprapubic tube in place to allow the massive pelvic hematoma to resorb and the acute inflammation to subside, which typically takes 3 to 6 months. Finally, once the tissues are stable and healed, a definitive delayed formal urethroplasty is performed.

Step-by-Step Solution

Recognize signs of posterior urethral injury

Identify that blood at the meatus, a scrotal hematoma, and a high-riding prostate in the setting of a pelvic fracture strongly suggest posterior urethral disruption.

These classic clinical findings contraindicate immediate blind transurethral Foley catheterization.

Determine the initial diagnostic test

Select a retrograde urethrogram (RUG) as the first intervention.

A RUG safely visualizes the urethra with contrast to confirm and delineate the disruption without causing additional mechanical trauma.

Determine the initial management after diagnosis

Select suprapubic cystostomy tube placement.

Because the urethra is disrupted, urine must be safely diverted away from the injury site to decompress the bladder.

Determine the timing and method of definitive repair

Sequence a waiting period followed by delayed formal urethroplasty.

Immediate open repair has high complication rates (e.g., massive bleeding, impotence); waiting allows the hematoma to resolve before complex reconstruction.

Key Concept

In patients with pelvic fractures and signs of urethral injury (blood at the meatus, high-riding prostate), a retrograde urethrogram must be performed before any catheterization. Complete posterior urethral injuries are managed initially with suprapubic cystostomy, followed by delayed urethroplasty.

Question 28Question →

A 29-year-old man presents to the emergency department with acute, agonizing pain in his groin. He reports that 2 hours ago, during vigorous sexual intercourse, he heard a distinct "snapping" sound, which was immediately followed by a loss of erection and rapid swelling of his penis. He states that he has felt a strong urge to urinate since the event but has been unable to pass any urine. Vital signs are within normal limits. Physical examination reveals a markedly swollen, ecchymotic penis that is severely deviated to the right. The scrotum is unremarkable, but there is a visible drop of fresh blood at the external urethral meatus. Which of the following is the most appropriate next step in the management of this patient?

Retrograde urethrography

Emergent surgical exploration of the corpora cavernosa

Insertion of a 16-French urethral catheter

Color Doppler ultrasonography of the penis

Placement of a percutaneous suprapubic cystostomy

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Answer: Retrograde urethrography

Answer

Retrograde urethrography

This patient's presentation of a snapping sound during intercourse followed by rapid detumescence, pain, and an ecchymotic, swollen, deviated penis (the "eggplant" deformity) is pathognomonic for a penile fracture. This condition involves the traumatic rupture of the tunica albuginea of the corpus cavernosum. While the definitive treatment for an isolated penile fracture is emergent surgical exploration and repair, this patient has signs highly concerning for a concomitant urethral injury: an inability to void and blood at the urethral meatus. Concomitant urethral injuries occur in up to 20% of penile fractures. When a urethral injury is suspected, a retrograde urethrogram (RUG) is the mandatory next step to evaluate the integrity of the urethra before any blind catheterization or surgical intervention is attempted.

Step-by-Step Solution

Analyze the mechanism of injury and physical exam findings.

The patient has a classic "eggplant" deformity, snapping sound, and rapid detumescence, establishing a clinical diagnosis of penile fracture (rupture of the tunica albuginea).

Recognizing the primary injury dictates the general treatment algorithm (surgical emergency).

Identify complicating clinical signs.

The presence of blood at the urethral meatus and an inability to void indicate a high probability of a concomitant urethral injury (occurring in up to 20% of penile fractures).

Complicating factors alter the standard management pathway and introduce absolute procedural contraindications.

Determine the appropriate diagnostic sequence based on the complicating signs.

Because a urethral injury is strongly suspected, a retrograde urethrogram must be performed to evaluate the urethral integrity before any blind catheterization or definitive surgical exploration is attempted.

Failing to image the urethra can lead to exacerbation of a partial tear or an unprepared surgical team during cavernosal repair.

Key Concept

In patients with a penile fracture who exhibit signs of concomitant urethral injury (e.g., blood at the meatus, gross hematuria, urinary retention), a retrograde urethrogram is the mandatory next step prior to surgical exploration.

Question 29Question →

A $65$ -year-old man comes to the clinic for a follow-up examination $6$ weeks after undergoing a radical cystectomy and urinary diversion via an ileal conduit for muscle-invasive urothelial carcinoma. Over the past two weeks, he has experienced progressive fatigue and generalized muscle weakness. His temperature is $37.6^\circ\text{C}$ ( $99.7^\circ\text{F}$ ), blood pressure is $118/76\text{ mm Hg}$ , pulse is $88/\text{min}$ , and respirations are $22/\text{min}$ . Physical examination shows a well-healed abdominal incision. The stoma is pink and viable, outputting clear yellow urine into the ostomy bag. The lungs are clear to auscultation bilaterally.

Laboratory studies are obtained:

Laboratory Test	Result
Sodium	$139\text{ mEq/L}$
Potassium	$3.2\text{ mEq/L}$
Chloride	$115\text{ mEq/L}$
Bicarbonate	$14\text{ mEq/L}$
Blood urea nitrogen	$20\text{ mg/dL}$
Creatinine	$1.2\text{ mg/dL}$

Arterial blood gas analysis on room air shows:
- pH: $7.28$
- pCO $_2$ : $28\text{ mm Hg}$
- pO $_2$ : $96\text{ mm Hg}$

Which of the following is the most appropriate next step in the management of this patient?

Placement of a nasogastric tube and initiation of bowel rest

Admission for blood cultures and empirical intravenous piperacillin-tazobactam

Initiation of oral potassium citrate therapy

Initiation of noninvasive positive pressure ventilation

Computed tomography of the abdomen and pelvis with intravenous contrast

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Answer: Initiation of oral potassium citrate therapy

Answer

Initiation of oral potassium citrate therapy

The correct answer is the administration of an oral alkalinizing agent that also replenishes potassium, such as potassium citrate. This patient has a normal anion gap metabolic acidosis (anion gap =

139 - [115 + 14] = 10

) with marked hyperchloremia and hypokalemia. This is a classic complication of urinary diversion utilizing an ileal conduit (or ureterosigmoidostomy). The ileal mucosa actively absorbs ammonium and chloride from the urine while secreting bicarbonate. The chronic metabolic acidosis and increased sodium delivery to the distal tubule promote renal potassium wasting, leading to hypokalemia. The patient's fatigue and muscle weakness are direct consequences of the hypokalemia and acidosis. Arterial blood gas analysis reveals a pCO

_2

28\text{ mm Hg}

, which exactly matches the expected respiratory compensation calculated by Winter's formula [Expected pCO

_2

(1.5 \times 14) + 8 = 29 \pm 2

]. Therefore, there is no primary respiratory disorder. Treatment consists of reversing the acidosis and replenishing potassium, making potassium citrate the ideal pharmacotherapy.

Step-by-Step Solution

Analyze the patient's acid-base status and electrolyte panel.

The anion gap is normal (

\text{Na}^+ - [\text{Cl}^- + \text{HCO}_3^-] = 139 - [115 + 14] = 10

). The patient has a hyperchloremic (

115\text{ mEq/L}

) normal anion gap metabolic acidosis with hypokalemia (

3.2\text{ mEq/L}

To identify the primary physiologic derangement causing the patient's fatigue and weakness.

Calculate the expected respiratory compensation using Winter's formula.

Expected pCO

_2

(1.5 \times 14) + 8 = 29 \pm 2\text{ mm Hg}

. The measured pCO

_2

28\text{ mm Hg}

represents appropriate and complete respiratory compensation.

To determine if the tachypnea and low pCO2 indicate a secondary respiratory failure or an appropriate compensatory mechanism.

Correlate the metabolic findings with the patient's surgical history of an ileal conduit.

The ileal segment used for the urinary diversion actively reabsorbs chloride and ammonium from the urine while secreting bicarbonate. This causes a hyperchloremic metabolic acidosis, which in turn leads to renal potassium wasting.

To establish the underlying etiology of the normal anion gap metabolic acidosis in a post-cystectomy patient.

Select the most appropriate pharmacotherapy to correct the underlying derangements.

Oral potassium citrate is selected because it provides base (citrate is metabolized to bicarbonate in the liver) and replenishes the potassium deficit.

To safely and effectively reverse the acidosis and hypokalemia without causing further complications.

Key Concept

Hyperchloremic normal anion gap metabolic acidosis and hypokalemia are classic complications of urinary diversion via an ileal conduit. Treatment involves oral alkalinization with potassium citrate.

Question 30Question →

An adolescent boy, age $16$ , presents to the triage desk reporting severe right-sided scrotal pain that awoke him from sleep approximately $90$ minutes ago. He has no prior medical history and does not report any recent sexual activity or trauma. His temperature is $37.0^\circ\text{C}$ ( $98.6^\circ\text{F}$ ), pulse is $105/\text{min}$ , and blood pressure is $120/75 \text{ mm Hg}$ . Genitourinary examination demonstrates a diffusely swollen, markedly tender right testicle with a transverse lie, positioned notably higher than the contralateral testis. Stroking the inner aspect of the right thigh produces no testicular elevation, whereas the reflex is intact on the left side. Which of the following is the most appropriate next step in the management of this patient?

Emergent surgical exploration

Scrotal duplex ultrasonography

Intramuscular ceftriaxone and oral doxycycline

Scrotal elevation and nonsteroidal anti-inflammatory drugs

Urinalysis and urine culture

Show answer & explanation

Answer: Emergent surgical exploration

Answer

Emergent surgical exploration

The correct answer is emergent surgical exploration. This patient's presentation of sudden-onset, severe unilateral scrotal pain that awoke him from sleep, combined with a high-riding, transversely oriented testicle and an absent cremasteric reflex, is highly specific for testicular torsion. Testicular torsion is a surgical emergency caused by the twisting of the spermatic cord, leading to venous congestion and subsequent arterial compromise. Because testicular salvage rates drop significantly after

6

hours of ischemia, definitive treatment with emergent surgical exploration and bilateral orchiopexy is required immediately. In cases where the clinical suspicion is unequivocally high, diagnostic imaging must be bypassed to avoid delaying surgical care.

Step-by-Step Solution

Analyze the patient's symptoms and physical examination findings.

The patient has sudden-onset severe scrotal pain, a high-riding testis with a transverse lie, and an absent cremasteric reflex.

These findings must be synthesized to determine the underlying etiology of the acute scrotum.

Establish the most likely clinical diagnosis.

The clinical picture is highly specific for testicular torsion.

The absence of the cremasteric reflex is the most sensitive physical exam finding for testicular torsion, distinguishing it from epididymitis or torsion of the appendix testis.

Determine the appropriate management for highly suspected testicular torsion.

Immediate urologic consultation and surgical exploration are required.

Testicular viability decreases rapidly after

6

hours of ischemia, making immediate surgery the standard of care without delaying for imaging.

Key Concept

Patients with a high clinical suspicion for testicular torsion (characterized by sudden-onset pain, high-riding testicle, and absent cremasteric reflex) should undergo emergent surgical exploration without delay for ultrasound imaging.

Question 31Question →

A physician evaluates a patient in the surgical triage area. The patient is a male in his late 50s with a 15-year history of poorly controlled type 2 diabetes mellitus. He presents with rapidly worsening genital pain and swelling over the past 24 hours, accompanied by high fevers and general malaise. His temperature is $39.2^\circ\text{C}$ ( $102.6^\circ\text{F}$ ), pulse is $122/\text{min}$ , and blood pressure is $92/58 \text{ mmHg}$ . Physical examination reveals a markedly edematous, erythematous scrotum and perineum. There are several patches of dark, purplish skin necrosis over the right hemiscrotum. Palpation of the affected area elicits exquisite pain along with a distinct crackling sensation beneath the skin. Laboratory studies show a leukocyte count of $24,500/\mu\text{L}$ with $15\%$ bands, and a serum glucose of $385 \text{ mg/dL}$ . Which of the following is the most appropriate immediate next step in management?

Emergent surgical exploration and wide debridement

Intravenous administration of broad-spectrum antibiotics and admission to the intensive care unit

Computed tomography of the abdomen and pelvis with intravenous contrast

Bedside needle aspiration of the scrotal tissue for gram stain and culture

Scrotal ultrasonography with Doppler color flow

Show answer & explanation

Answer: Emergent surgical exploration and wide debridement

Answer

Emergent surgical exploration and wide debridement

The correct action is emergent surgical exploration and wide debridement. This patient's presentation of high fever, hemodynamic instability, scrotal skin necrosis, and crepitus (subcutaneous gas) in the setting of poorly controlled diabetes is pathognomonic for Fournier gangrene. This is a fulminant necrotizing fasciitis of the perineum and external genitalia. Because the infection spreads rapidly along fascial planes and is highly lethal, the single most critical step in management is immediate surgical source control to excise all non-viable tissue. While broad-spectrum antibiotics and fluid resuscitation are initiated simultaneously, surgery must not be delayed.

Step-by-Step Solution

Identify the primary clinical syndrome based on vital signs and physical examination.

The patient has systemic toxicity (hypotension, fever, tachycardia, profound leukocytosis) paired with severe perineal pain, skin necrosis, and palpable crepitus.

These findings are the hallmark of necrotizing fasciitis of the perineal and genital region, known as Fournier gangrene.

Identify the pathophysiology and primary risk factors associated with the diagnosis.

Fournier gangrene is a rapidly progressive, polymicrobial infection that spreads along fascial planes (Colles, Dartos, and Scarpa fascia). Poorly controlled diabetes mellitus is a classic predisposing risk factor.

Understanding the aggressive spread along fascial planes dictates the urgency and extent of the required intervention.

Determine the most appropriate immediate next step in management for a hemodynamically unstable patient with a clinically obvious necrotizing infection.

Immediate surgical exploration and wide debridement of all necrotic tissue is required.

Surgical source control is the single most important determinant of survival in necrotizing fasciitis. Delaying surgery for any reason, including imaging or awaiting the effects of antibiotics, significantly increases mortality.

Key Concept

Fournier gangrene is a life-threatening necrotizing fasciitis of the perineum and scrotum that requires immediate surgical exploration and wide debridement; clinical diagnosis (crepitus, skin necrosis) should prompt surgery without delaying for imaging.

Question 32Question →

A $24$ -year-old man is brought to the emergency department after colliding with a tree while downhill skiing. He reports severe, continuous pain in his right flank and right upper quadrant. His temperature is $37.1^\circ$ C ( $98.8^\circ$ F), blood pressure is $118/76$ mmHg, pulse is $92$ /min, and respirations are $16$ /min. Physical examination reveals a $15$ -cm area of ecchymosis over the right flank with marked tenderness to palpation. The abdomen is soft without rebound tenderness or guarding. Urinalysis demonstrates gross hematuria. A focused assessment with sonography for trauma (FAST) is negative for intraperitoneal free fluid. Computed tomography of the abdomen and pelvis with intravenous contrast reveals a $3.5$ -cm laceration of the right kidney that extends deep into the renal medulla and collecting system. Delayed-phase imaging demonstrates pooling of contrast medium in the perirenal space. There is a moderate, non-expanding perirenal hematoma, but no evidence of active arterial extravasation (blush). Which of the following is the most appropriate next step in management?

Hospital admission for bed rest and serial hemodynamic monitoring

Immediate exploratory laparotomy with primary renorrhaphy

Cystourethroscopy with retrograde ureteral stent placement

Renal angiography with selective arterial embolization

Initiation of intravenous broad-spectrum antibiotics and percutaneous urinoma drainage

Show answer & explanation

Answer: Hospital admission for bed rest and serial hemodynamic monitoring

Answer

The most appropriate next step is hospital admission for bed rest and serial hemodynamic monitoring.

The correct management is hospital admission for bed rest and serial hemodynamic monitoring. This patient has sustained a blunt Grade IV renal injury, characterized by a parenchymal laceration extending into the collecting system with resulting urinary extravasation. A high-yield and frequently tested principle in urologic trauma is that hemodynamic stability—not the grade of the injury—drives the decision for surgery. In the absence of hemodynamic instability, expanding/pulsatile hematoma, or active arterial extravasation, even high-grade renal injuries (Grades III-V) with urinary leaks are managed conservatively. The contained retroperitoneal space allows most urinary extravasations to heal spontaneously without surgical or endoscopic intervention.

Step-by-Step Solution

Assess the patient's hemodynamic status and overall trauma survey.

The patient is hemodynamically stable (BP

118/76

, HR

92

) with a negative FAST exam, ruling out immediate life-threatening intraperitoneal hemorrhage.

Hemodynamic stability dictates whether a trauma patient proceeds to immediate surgical exploration or advanced imaging.

Interpret the CT scan findings to grade the renal injury.

The CT shows a

3.5

-cm laceration extending into the collecting system with urinary extravasation but no active arterial bleeding, classifying this as an AAST Grade IV renal injury.

Accurate grading of the renal injury determines the specific management algorithm.

Select the appropriate intervention based on stability and injury grade.

Because the patient is stable and lacks active arterial hemorrhage, conservative management is indicated despite the presence of urinary extravasation.

Over

90\%

of blunt renal injuries, including Grade IV injuries with urinary leaks, resolve spontaneously with conservative management (bed rest, observation, serial hematocrits).

Key Concept

Hemodynamically stable blunt renal trauma, including high-grade injuries with urinary extravasation, should initially be managed conservatively with bed rest and observation.

Estimated Time:1m 30s

Question 33Question →

Match each clinical presentation below with the most appropriate definitive surgical intervention.

Click a left item, then click its matching right item

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Answer

The correct matches align each distinct urologic pathology with its gold-standard surgical management: small renal mass to partial nephrectomy, UPJ obstruction to pyeloplasty, testicular tumor to radical inguinal orchiectomy, and medically refractory BPH to TURP.

Each clinical scenario presents a classic indication for a specific urologic surgery. Nephron-sparing surgery is preferred for small renal masses. UPJ obstruction requires pyeloplasty. Testicular cancer necessitates an inguinal approach to avoid lymphatic seeding. Refractory BPH of moderate size is best managed with TURP.

Step-by-Step Solution

Analyze the first presentation (3.2 cm exophytic renal mass).

Identified as a stage T1a renal tumor.

Masses under 4 cm that are exophytic are prime candidates for nephron-sparing surgery.

Analyze the second presentation (hydronephrosis without hydroureter, pain with fluid intake).

Identified as ureteropelvic junction (UPJ) obstruction.

The lack of distal ureteral dilation localizes the obstruction to the UPJ, and dietzel syndrome (pain with diuresis) is a classic finding, requiring reconstruction.

Analyze the third presentation (painless, solid intratesticular mass).

Identified as highly suspicious for primary testicular malignancy.

Solid intratesticular masses require extirpation via the inguinal route to prevent altering the lymphatic drainage pattern.

Analyze the fourth presentation (refractory urinary retention, 45 mL prostate).

Identified as medically refractory benign prostatic hyperplasia.

Surgical de-obstruction is indicated; a 45 mL volume is well-suited for a standard transurethral approach rather than an open or simple prostatectomy.

Key Concept

Definitive surgical management of common urologic pathologies

Question 34Question →

A 55-year-old woman is brought to the emergency department from a nursing facility due to fever, severe left-sided back pain, and altered mental status. Her blood pressure is 85/50 mmHg, heart rate is 122/min, and temperature is 39.4°C (102.9°F). Laboratory studies show a leukocyte count of 19,000/mm³. A non-contrast CT scan of the abdomen and pelvis reveals an 8-mm radiopaque calculus in the proximal left ureter with associated moderate hydroureteronephrosis and perinephric stranding. Arrange the following management steps in the most appropriate chronological sequence for this patient.

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Answer

The correct chronological sequence is: 1) Intravenous fluids and broad-spectrum antibiotics, 2) Urgent placement of a percutaneous nephrostomy tube or ureteral stent, 3) Definitive ureteroscopic stone extraction, and 4) Outpatient 24-hour urine collection.

In cases of obstructive pyelonephritis with sepsis, the strict chronological order of management is: First, initial medical stabilization (intravenous fluids and broad-spectrum antibiotics); Second, emergent source control by draining the infected system (percutaneous nephrostomy or ureteral stent); Third, delayed definitive management of the obstructing stone (lithotripsy) once the infection has cleared; and finally, long-term preventative care (metabolic evaluation) in the outpatient setting.

Step-by-Step Solution

Identify the primary clinical emergency in the presentation.

The patient has obstructive pyelonephritis progressing to septic shock, indicated by hypotension, tachycardia, fever, leukocytosis, and an obstructing ureteral stone.

Recognizing life-threatening sepsis dictates the immediate need for medical stabilization before any surgical intervention is attempted.

Determine the requirement for urgent surgical source control.

Following initial medical stabilization, the infected urine must be drained via a percutaneous nephrostomy tube or a double-J ureteral stent.

An obstructed, infected kidney represents a closed-space infection (pus under pressure); without drainage, sepsis will rapidly progress despite antibiotic therapy.

Establish the correct timing for definitive stone management and secondary prevention.

Ureteroscopy with lithotripsy is delayed until the patient is completely infection-free. The metabolic evaluation is delayed even further into the outpatient recovery period.

Manipulating a stone during active infection risks systemic dissemination of bacteria. Furthermore, metabolic testing during acute illness yields inaccurate results.

Key Concept

Sequential management of obstructive pyelonephritis and urosepsis

Question 35Question →

An ill-appearing 58-year-old man is evaluated in the emergency department for severe perineal pain, chills, and an inability to pass urine for the past 12 hours. His temperature is 39.2°C (102.6°F), blood pressure is 105/65 mmHg, and heart rate is 112/min. Digital rectal examination demonstrates an exquisitely tender, warm, and swollen prostate gland. A bedside bladder scan reveals 700 mL of retained urine. Arrange the following interventions in the most appropriate chronological sequence for the management of this patient, progressing from immediate medical steps to procedural intervention and definitive surgical management of potential complications.

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Answer

The correct chronological sequence is to first obtain microbiological cultures, then administer empiric intravenous antibiotics, followed by a suprapubic cystostomy for safe bladder decompression, and finally surgical drainage if an abscess forms and fails to respond to medical therapy.

The precise chronological management of acute bacterial prostatitis complicated by acute urinary retention demands immediate culture acquisition prior to antibiotics. This is followed by safe bladder decompression using a suprapubic cystostomy to avoid traversing the inflamed prostate, with surgical drainage reserved strictly as a final step for refractory abscesses.

Step-by-Step Solution

Obtain blood and urine cultures

Baseline microbiological data is secured before it can be altered by medications.

Crucial for antibiotic stewardship to allow de-escalation of broad-spectrum antibiotics once sensitivities are known.

Administer empiric intravenous antibiotics

Systemic treatment for acute bacterial prostatitis is initiated.

The patient exhibits signs of systemic inflammatory response syndrome (fever, tachycardia) and requires immediate antimicrobial therapy.

Perform percutaneous suprapubic cystostomy

The bladder is decompressed safely without urethral instrumentation.

Urethral catheterization is contraindicated in acute bacterial prostatitis due to the high risk of inducing septic shock and causing extreme pain.

Perform transurethral unroofing and surgical drainage

Infected fluid collections are evacuated from the prostate.

This is a definitive surgical step reserved only for cases that progress to a prostatic abscess unresponsive to conservative management.

Key Concept

In acute bacterial prostatitis with urinary retention, prioritize cultures before antibiotics, decompress the bladder via suprapubic cystostomy to avoid prostatic trauma, and reserve surgical drainage for refractory abscesses.

Estimated Time:1m 30s

Question 36Question →

Match each clinical presentation of a scrotal or testicular mass to its most appropriate definitive management.

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Answer

The solid intratesticular mass requires radical inguinal orchiectomy. The benign spermatocele requires observation. The varicocele is managed with varicocelectomy. The communicating hydrocele in an infant requires ligation of the patent processus vaginalis.

Each clinical presentation perfectly matches a classic urologic condition with a standardized management protocol. Solid intratesticular masses are managed oncologically with inguinal orchiectomy. Benign cysts (spermatoceles) are observed. Varicoceles that are symptomatic receive varicocelectomy. Persistent communicating hydroceles in toddlers receive surgical ligation.

Step-by-Step Solution

Evaluate the solid intratesticular mass in the young adult.

Identify high suspicion for testicular malignancy.

Any solid testicular mass must be treated as cancer, making radical inguinal orchiectomy the correct immediate definitive step.

Evaluate the transilluminating, cystic epididymal mass.

Identify a benign spermatocele.

These lesions are entirely benign and do not affect fertility or health, so observation is appropriate.

Evaluate the left-sided mass that decompresses when supine.

Identify a varicocele.

Symptomatic varicoceles are managed definitively with varicocelectomy to alleviate pain or improve fertility parameters.

Evaluate the fluctuating scrotal swelling in a 1-year-old.

Identify a persistent communicating hydrocele.

Failure of the processus vaginalis to close by 12 months of age necessitates surgical ligation.

Key Concept

Definitive surgical management of scrotal and testicular masses

Estimated Time:1m 0s

Question 37Question →

A 31-year-old man presents to the emergency department with a painful, fully rigid erection that has persisted for 18 hours. He admits to recreational cocaine use the previous evening. Physical examination reveals tense, tender corpora cavernosa with a completely flaccid glans penis and corpus spongiosum. Arrange the following diagnostic and therapeutic interventions in the correct escalating sequence for managing this condition, assuming each successive step fails to achieve permanent detumescence.

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Answer

The correct sequential algorithm for ischemic priapism is: 1) Corporal blood gas analysis, 2) Intracavernosal aspiration and irrigation, 3) Intracavernosal sympathomimetic injection, 4) Distal corporoglans shunt, 5) Proximal cavernosum-spongiosum shunt.

Ischemic priapism is a compartment syndrome of the corpora cavernosa resulting in severe hypoxia and potential necrosis of erectile tissue. The standard-of-care escalating algorithm requires diagnostic confirmation with a corporal blood gas first. Once confirmed, the least invasive therapeutic option—intracavernosal aspiration and saline irrigation—is performed. If the erection persists, an intracavernosal alpha-agonist (such as phenylephrine) is injected to stimulate venous outflow via smooth muscle contraction. If these conservative measures fail, surgical intervention is mandated to prevent permanent corporal fibrosis. A distal corporoglans shunt (e.g., Winter procedure) is performed first. Only if the distal shunt fails is a proximal cavernosum-spongiosum shunt (e.g., Quackels procedure) attempted, as proximal shunts carry a significantly higher risk of permanent erectile dysfunction.

Step-by-Step Solution

Differentiate ischemic from non-ischemic priapism.

Corporal blood gas analysis.

Blood gas confirms hypoxia and acidosis, differentiating the true urologic emergency of an ischemic compartment syndrome from non-ischemic (high-flow) priapism.

Attempt initial mechanical decompression.

Intracavernosal aspiration and irrigation.

Removing sludged, hypoxic blood directly reduces intracorporal pressure and may re-establish normal arterial inflow.

Attempt pharmacological smooth muscle contraction.

Intracavernosal phenylephrine injection.

Alpha-adrenergic stimulation induces cavernosal smooth muscle contraction, forcing blood into the venous outflow channels and resolving the veno-occlusive crisis.

Perform initial surgical decompression.

Distal corporoglans shunt.

If non-surgical management fails, a distal shunt is preferred first because it is technically simpler, can be performed under local anesthesia, and carries a lower risk profile for future erectile function.

Perform advanced surgical decompression.

Proximal cavernosum-spongiosum shunt.

This is reserved for cases refractory to distal shunting due to the high likelihood of permanent, severe erectile dysfunction and potential for urethral injury.

Key Concept

The algorithmic management of ischemic priapism progresses strictly from diagnosis (blood gas) to mechanical therapy (aspiration), pharmacological therapy (phenylephrine), and escalating surgical shunts (distal before proximal).

Question 38Question →

A $72$ -year-old man is brought to the emergency department due to severe lower abdominal pain and an inability to pass urine for the past $18$ hours. He has a history of benign prostatic hyperplasia for which he takes tamsulosin inconsistently. His temperature is $37.1^\circ\text{C}$ , blood pressure is $155/92\text{ mmHg}$ , pulse is $102/\text{min}$ , and respiratory rate is $16/\text{min}$ . Physical examination reveals a distressed patient in apparent pain. The abdomen is non-distended, but there is a palpable, tender, rounded mass extending from the pubic symphysis to the umbilicus. Digital rectal examination reveals a diffusely enlarged, smooth, and firm prostate without nodules. Which of the following is the most appropriate next step in management?

Placement of a urethral Foley catheter

Non-contrast CT scan of the abdomen and pelvis

Empiric administration of intravenous ciprofloxacin

Administration of intravenous fluids and observation

Measurement of serum prostate-specific antigen levels

Show answer & explanation

Answer: Placement of a urethral Foley catheter

Answer

Placement of a urethral Foley catheter is the most appropriate next step.

The correct action is the placement of a urethral Foley catheter. This patient's presentation of severe suprapubic pain, inability to void, and a palpable suprapubic mass is the classic triad of acute urinary retention (AUR). Given his history of benign prostatic hyperplasia (BPH) and medication non-adherence, mechanical outflow obstruction is the definitive cause. The immediate, primary goal in AUR is to decompress the bladder to relieve the patient's severe pain and to prevent permanent bladder dysfunction or post-renal acute kidney injury. Urethral catheterization is the safest, most rapid, and most effective first-line method to achieve this.

Step-by-Step Solution

Analyze the patient's clinical presentation and physical exam findings.

The patient has severe lower abdominal pain, an inability to void for 18 hours, and a tender suprapubic mass, which represents a distended bladder.

Identifying the classic signs of acute urinary retention is essential for determining the need for emergent intervention.

Determine the underlying etiology based on the history.

The patient has a history of benign prostatic hyperplasia and inconsistent medication adherence, strongly suggesting BPH as the cause of obstruction.

Understanding the obstructive nature of the etiology guides the choice of mechanical decompression.

Select the most appropriate immediate intervention.

Urethral catheterization is the standard first-line treatment.

Immediate decompression relieves severe discomfort and prevents complications such as detrusor muscle damage and post-renal acute kidney injury.

Key Concept

The immediate management of acute urinary retention is prompt bladder decompression, most commonly achieved with a urethral Foley catheter.

Question 39Question →

A 55-year-old woman is brought to the emergency department due to a 1-day history of severe left flank pain, shaking chills, and confusion. Her temperature is $39.4^\circ\text{C}$ ( $102.9^\circ\text{F}$ ), blood pressure is $82/50\text{ mm Hg}$ , pulse is $122/\text{min}$ , and respiratory rate is $22/\text{min}$ . Physical examination reveals severe left costovertebral angle tenderness. Laboratory studies show a leukocyte count of $18,500/\text{mm}^3$ with a left shift. A non-contrast computed tomography (CT) scan of the abdomen and pelvis reveals a 9-mm obstructing calculus in the proximal left ureter associated with moderate left hydroureteronephrosis and perinephric stranding. Arrange the following interventions in the most appropriate chronological order for the standard management of this patient.

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Answer

The correct chronological order is: 1) Initiate aggressive intravenous fluid resuscitation and broad-spectrum antibiotics, 2) Perform emergent decompression of the infected collecting system, 3) Continue targeted antimicrobial therapy and supportive care until clinical stability is achieved, 4) Perform definitive elective stone extraction.

The standard of care for obstructive pyelonephritis with sepsis follows a strict, life-saving sequence: initial medical resuscitation (fluids and broad-spectrum antibiotics), emergent source control (decompression via a ureteral stent or percutaneous nephrostomy tube), a period of clinical stabilization, and finally, delayed definitive treatment of the calculus. Immediate resuscitation addresses the life-threatening septic shock. Decompression relieves the high-pressure infected system, allowing for proper source control. Once decompressed, the patient must recover from the systemic illness before undergoing elective definitive stone surgery. Attempting definitive stone removal during the acute septic episode is absolutely contraindicated due to the risk of exacerbating sepsis through high-pressure irrigation.

Step-by-Step Solution

Recognize the clinical syndrome.

The patient has obstructive pyelonephritis progressing to septic shock, indicated by high fever, hypotension, altered mental status, and a ureteral stone causing hydronephrosis.

Accurate diagnosis is required to prioritize life-saving interventions over standard definitive stone management.

Determine the immediate life-saving priority.

Intravenous fluid resuscitation and broad-spectrum antibiotics must be initiated first.

Hemodynamic stabilization and early administration of antibiotics are the cornerstones of surviving septic shock.

Identify the next necessary step for source control.

Emergent decompression of the collecting system (via ureteral stent or percutaneous nephrostomy) must be performed.

Antibiotics alone are ineffective for a closed-space infection in the urinary tract; the purulent urine under pressure must be drained.

Determine the timing for definitive stone treatment.

Definitive stone extraction is delayed until after full clinical recovery.

Performing lithotripsy in an actively infected system forces bacteria into the bloodstream via high-pressure irrigation, which can precipitate fatal sepsis.

Key Concept

Management Sequence for Obstructive Pyelonephritis

Estimated Time:1m 15s

Question 40Question →

A $42$ -year-old man with a history of Crohn disease and multiple prior ileal resections presents to the clinic for follow-up of a recent episode of right-sided flank pain. The pain began two days ago, radiated to his groin, and has since resolved completely after he took ibuprofen. He has chronic, non-bloody diarrhea but currently feels well. His temperature is $37.1^\circ\text{C}$ ( $98.8^\circ\text{F}$ ), blood pressure is $120/80 \text{ mm Hg}$ , and pulse is $78/\text{min}$ . Physical examination demonstrates a soft, non-tender abdomen with mild right costovertebral angle tenderness. Laboratory testing reveals a serum creatinine of $0.9 \text{ mg/dL}$ . Urinalysis shows a pH of $5.0$ , $15-20 \text{ RBCs/hpf}$ , and no leukocyte esterase or nitrites. A kidney, ureter, and bladder (KUB) radiograph demonstrates no radiopaque abnormalities. A subsequent non-contrast CT scan of the abdomen and pelvis reveals a $1.6\text{-cm}$ calculus in the right renal pelvis causing mild hydronephrosis. Which of the following is the most appropriate next step in management of this patient's calculus?

Oral potassium citrate

Extracorporeal shock wave lithotripsy

Percutaneous nephrolithotomy

Ureteroscopic stone extraction

Oral allopurinol

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Answer: Oral potassium citrate

Answer

Oral potassium citrate

The correct answer is oral potassium citrate because the patient's presentation is classic for a uric acid stone, which can be managed medically rather than surgically. Chronic diarrhea from Crohn disease leads to significant gastrointestinal bicarbonate loss. This causes a chronic metabolic acidosis, resulting in highly acidic urine (pH 5.0) as the kidneys attempt to compensate. Uric acid is highly insoluble in acidic environments and readily precipitates. Characteristically, uric acid stones are radiolucent (invisible on KUB radiographs) but can be clearly visualized on CT scans. While a 1.6-cm renal calculus of any other composition would typically require surgical intervention (such as ESWL or PCNL), large uric acid stones in stable, uninfected patients are the major exception. They can be completely dissolved through urinary alkalinization (raising the pH to 6.0-6.5) using oral potassium citrate, effectively treating the stone without invasive procedures.

Step-by-Step Solution

Analyze the patient's history and imaging findings to identify the stone composition.

The patient has Crohn disease with chronic diarrhea (leading to metabolic acidosis and acidic urine), a radiolucent stone on KUB, and a visible stone on CT.

This specific triad of findings is highly diagnostic for a uric acid stone, which behaves differently from calcium oxalate or struvite stones.

Evaluate the clinical status and stone size/location.

The patient is hemodynamically stable, currently pain-free, with normal renal function and a 1.6-cm non-infected renal pelvic stone.

This confirms there is no indication for emergent decompression (e.g., nephrostomy) and allows for elective definitive therapy.

Select the definitive therapy based on stone composition.

Urinary alkalinization with oral potassium citrate.

Uric acid solubility increases exponentially as urine pH rises above 6.0. Alkalinization can completely dissolve large uric acid stones, sparing the patient from surgery.

Key Concept

Diagnosis and non-surgical management of uric acid nephrolithiasis via urinary alkalinization.

Estimated Time:2m 0s

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