Can a pelvic fracture cause hematuria (presence of blood in the urine) in a patient, particularly those with a history of bleeding disorders or significant trauma?

Can Pelvic Fracture Cause Hematuria?

Yes, pelvic fractures frequently cause hematuria, and the combination of pelvic fracture with gross hematuria is a critical indicator of genitourinary injury that demands immediate imaging evaluation.

Epidemiology and Clinical Significance

Hematuria is present in 88-94% of cases of renal/urogenital trauma, though it does not predict the grade of injury 1. When specifically examining pelvic fractures:

• All patients with bladder rupture from pelvic fracture present with hematuria 2, 3
• 6-8% of patients with pelvic fractures will have bladder injury 1
• When pelvic fracture is combined with gross hematuria, bladder injury occurs in approximately 30% of cases 1
• 85% of bladder rupture patients have an associated pelvic fracture 4

Mechanism of Injury

The genitourinary tract is vulnerable during pelvic trauma through several mechanisms:

• Bladder rupture occurs in 60-90% of bladder injuries associated with pelvic fractures, with extraperitoneal rupture being most common 1
• Urethral injury (particularly posterior urethra) occurs in 1.5-5% of anterior pelvic fractures, with risk increasing 10% for every 1-mm increase in pubic symphysis diastasis 1
• Blood at the urethral meatus in patients with pelvic fractures indicates a 50% incidence of genitourinary injury 1

Critical Clinical Algorithm

When to Image for Genitourinary Injury:

Absolute indications for immediate cystography:

• Pelvic fracture + gross hematuria (this combination constitutes an absolute indication) 4, 3
• Blood at urethral meatus with pelvic fracture 1

Consider imaging with pelvic fracture when:

• Specific fracture patterns present: pubic symphysis diastasis >1 cm (RR 9.8) or obturator ring fracture with displacement >1 cm (RR 3.2) 5
• Clinical indicators: inability to void, low urine output, suprapubic tenderness, abdominal distension, elevated BUN/creatinine 1, 6

May defer imaging:

• Isolated microscopic hematuria (<30 RBC/HPF) without pelvic fracture 5, 3
• Isolated acetabular fractures (no bladder injuries reported in this pattern) 5
• Pelvic fracture without any hematuria 2, 3

Diagnostic Approach

For suspected bladder injury:

• Perform retrograde cystography with minimum 300 mL contrast or until patient tolerance 6, 7
• CT cystography has 95-100% sensitivity and 99-100% specificity 7
• Never rely on passive IV contrast accumulation—this has high false-negative rates 1, 7

For suspected urethral injury:

• Perform retrograde urethrography before attempting catheterization 1
• Look for blood at meatus, inability to void, perineal hematoma, high-riding prostate 1

Critical Pitfalls to Avoid

• Do not attribute hematuria to anticoagulation without imaging when pelvic fracture is present—29% of patients with this combination have bladder rupture 6
• Do not delay imaging in hemodynamically stable patients with gross hematuria and pelvic fracture—this is an absolute indication 4, 3
• Do not attempt urethral catheterization before urethrography if urethral injury is suspected 1
• Do not assume microscopic hematuria alone requires imaging—existing data do not support routine imaging for microscopic hematuria with pelvic fracture 4, 3

Special Populations

Pediatric patients:

• More susceptible to bladder injuries due to anatomy, but injuries are less associated with pelvic fractures than in adults 1
• Hematuria is absent in 36-40% of renal injuries and up to 24% of renal artery occlusions 1
• Consider imaging with >50 RBC/HPF plus mechanism of injury, hypotension, flank findings, or rib fractures 1