• Clinical science

Genitourinary trauma

Abstract

Genitourinary trauma involves injury to the kidneys, ureters, bladder, and/or urethra. It may result in high morbidity if not properly identified and managed. The diagnosis of genitourinary trauma typically relies on patient history, physical examination, urinalysis, and imaging (CT, cystoscopy, retrograde urethrogram). Renal trauma is most often an acute condition caused by a blunt abdominal injury and may, if severe, represent a urological emergency. The classical symptoms of renal trauma are hematuria and pain in the affected side following injury. Mild trauma generally only requires monitoring, while high-grade injury may require emergency surgery and intensive care. Injury to the ureters is rare and generally iatrogenic, occurring mostly during operative procedures. Management may require stent placement with surgical repair. Bladder injuries are common in blunt abdominal trauma. Classic symptoms are gross hematuria, an inability to void, and abdominal pain. Extraperitoneal bladder injuries usually resolve with catheterization, while intraperitoneal injury requires surgery, which can help to prevent peritonitis and urosepsis. Urethral injuries may involve the posterior urethra, causing a high-riding prostate and blood at the urethral meatus, or the anterior urethra, causing perineal pain or hematoma. Treatment may be conservative or surgical depending on the severity of injury. Complications include urinary extravasation, urinoma, abscess formation, renal hypertension, and loss of function in the affected kidney.

Etiology

Renal and ureteral injuries

Bladder injuries

Urethral injuries

  • Anterior urethral injuries:
    • Direct trauma to perineum (direct blow, straddle injury); : bulbous urethra is most commonly injured
    • In conjunction with penile fracture
    • Iatrogenic (instrumentation of urethra)
  • Posterior urethral injuries:
    • Significant pelvic fractures due to trauma (automobile collisions)
  • Less common in women due to a shorter and more mobile urethra

In patients with pelvic fractures, always evaluate for possible injury to the genitourinary system!

References:[1][2][3][4][5][6][7]

Classification

Renal trauma

Outline of renal trauma according to the American Association for Surgery of Trauma (1995)
Grade Morphology
I Renal contusion with subcapsular hematoma
II Renal parenchymal rupture < 1 cm with retroperitoneal hematoma
III Renal parenchymal rupture > 1 cm with retroperitoneal hematoma; without urinoma
IV Parenchymal rupture until the renal pelvis with segmental malfunction and urinoma
V Completely ruptured kidney with hilar vascular dissection and total malfunction

Clinical features

Renal and ureteral injuries

Bladder injuries

  • Extraperitoneal and/or intraperitoneal injury
    • Gross hematuria (majority of cases)
    • Inability to void
    • Pain in the lower abdomen
  • Intraperitoneal injury
    • Peritoneal irritation
    • Increasing retention parameters through peritoneal resorption of creatinine

Urethral injuries

Findings upon examination
Both types
Anterior urethral injury
Posterior urethral injury
  • High-riding prostate on exam
  • Inability to void despite urge → palpably distended bladder
  • Suprapubic pain


Injury to the urinary system can be easily masked by multiple concurrent injuries to other organ systems and is therefore easily overlooked!
References:[1][2][8]

Diagnostics

General approach to genitourinary trauma

  • Patient history
  • Physical examination
  • Urinalysis with microscopy: macrohematuria (urine not clear or yellow) or microscopic hematuria
    • The color of the urine does not correlate with injury severity!
    • Microscopic hematuria after significant (nonurethral) trauma is common; no further diagnostic tests are needed in patients who are hemodynamically stable and present without any other signs or symptoms of associated pelvic or abdominal inury
  • Blood analysis: exclude anemia due to blood loss; assess renal function (creatinine)

Evaluate the genitourinary tract in a retrograde fashion, beginning with the external genitalia and urethra!

Renal and ureteral injury

  • CT with IV contrast of the abdomen/pelvis: to assess renal and accompanying injuries or intra-abdominal fluid retention
  • Delayed CT imaging: indicated if injury to the renal pelvis and ureters is suspected
  • IV pyelography: : to assess for contrast extravasation if delayed CT images are nondiagnostic
  • Urethrocystography: if CT is unavailable

Bladder injury

  • Retrograde cystography or retrograde CT cystography: to assess for bladder rupture in patients with gross hematuria (can be seen in Foley catheter if it has been placed) or microscopic hematuria and pelvic fracture
    • Do not perform urethrogram or cystogram if severe pelvic vascular injury is suspected!

Urethral injury

  • Retrograde urethrogram: to rule out suspected urethral injury
    • This should be the first diagnostic step in a patient with suspected traumatic injury to the genitourinary track!
    • Contrast extravasation from the urethra at point of injury
      • If some contrast enters the bladder → partial injury
      • If no contrast enters the bladder → complete injury
  • Foley catheter placement: : in cases of gross hematuria without other signs of urethral injury (see clinical features), a single attempt at Foley catheter placement may be attempted
  • Ultrasonography: particularly of the kidney and bladder; used to clarify whether a perirenal hematoma or urinoma is present, though this cannot reliably differentiate between or rule out significant renal injuries

A negative urinalysis does not exclude renal injury because not all injuries affect the renal pelvis and urinary tract!

References:[1][9]

Treatment

General

  • Hemodynamically stable patients with minor trauma: observe with Foley catheter placement, if needed, for hematuria and/or oliguria
  • Hemodynamically unstable patients: may require immediate surgical intervention for other injuries prior to definitive treatment of genitourinary injuries

Renal and ureteral trauma

Low-grade renal injury

  • Observation and vital sign monitoring with bed rest
  • Antibiotic prophylaxis
  • Monitor for hematuria

High-grade renal injury

  • Stable hemodynamics
    • Conservative measures
    • Ensure adequate urine flow with double-J ureteral stent
  • Unstable hemodynamics: emergent exploration; with surgical defect repair and possible nephrectomy to prevent life-threatening bleeding

Ureteral trauma

  • Cystoscopic stent placement with surgical repair over stent if needed
  • May require urinary diversion

Conservative

  • Grades I–III with a stable circulatory system
    • Bed rest
    • Monitoring of vital signs
    • Administration of an antibiotic prophylaxis

Endoscopy

  • Grade IV with a stable circulatory system
    • Conservative measures as indicated for grades I–III
    • Ensure adequate urine flow
  • Ureteral injury: cystoscopic stent placement

Surgical

  • Grade V, and/or cardiovascular failure, and/or > 25% of a segmental malfunction, and/or massive urinoma, and/or removal of a foreign body
    • Transperitoneal exposure of the kidney and coverage of the defect
    • Potential nephrectomy
  • Ureteral injury: surgical repair over stent with possible urinary diversion

Bladder injuries

  • Goal is to keep bladder decompressed → minimizes bladder wall tension to facilitate healing
    • No urethral injury: place Foley catheter to drain bladder; irrigate bladder to clear clots
    • Extraperitoneal injury without involvement of bladder neck: insertion of a transurethral indwelling catheter; otherwise suprapubic urinary diversion
    • Extraperitoneal injuries involving bladder neck: : associated with rectal/vaginal injury and all intraperitoneal injuries (i.e., bladder dome) → open surgical repair

Urethral injuries

  • The goal is to maintain urinary continence and sexual function.
  • Place suprapubic catheter to decompress bladder (diverts urine from the healing urethra and anastomosis)
  • Anterior urethral injury
    • Partial injury: place Foley catheter for healing by secondary intention
    • Penetrating injury: surgical exploration with debridement and defect repair with a direct anastomosis over a catheter
  • Posterior urethral injury
    • Endoscopic approach: early realignment (within 1 week) with combined transurethral and percutaneous transvesical approach
    • Surgical approach: place suprapubic catheter delayed urethroplasty (6–12 weeks after initial injury)

References:[1][10][11]

Complications

References:[2][12]

We list the most important complications. The selection is not exhaustive.