What is the final diagnosis for a patient who experienced a fall and is now presenting with transient and reversible bladder dysfunction?

Transient Neurogenic Bladder Dysfunction Secondary to Fall-Related Trauma

The final diagnosis is transient neurogenic bladder dysfunction secondary to fall-related trauma, most likely representing bladder contusion or temporary neurological impairment affecting bladder control. 1

Diagnostic Reasoning

Primary Consideration: Bladder Contusion

• Bladder contusion requires no specific treatment and can be observed clinically, as it represents a reversible injury that typically resolves spontaneously 1
• Falls are frequently associated with reversible factors affecting bladder function, including direct trauma to the lower urinary tract and temporary neurological dysfunction 1
• The transient and reversible nature of the bladder dysfunction strongly suggests a self-limited injury rather than structural damage requiring surgical intervention 1

Differential Considerations to Exclude

Structural bladder injury must be ruled out through appropriate imaging:

• Bladder rupture (intraperitoneal or extraperitoneal) would present with persistent symptoms, hematuria, and inability to void, requiring CT cystography for definitive diagnosis 1
• Intraperitoneal bladder rupture can cause urinary ascites and pseudo-renal failure with elevated creatinine, which would not be transient 2
• Extraperitoneal bladder injuries may be managed non-operatively with catheter drainage if uncomplicated 1

Neurogenic bladder from spinal cord injury should be considered:

• Falls can cause traumatic spinal cord injury leading to bladder dysfunction, but this typically presents with persistent rather than transient symptoms 3, 4
• Presence of voluntary anal contraction (VAC) is a key clinical indicator that helps predict recovery of bladder function after spinal trauma 4
• Absence of VAC correlates with 95.7% likelihood of persisting impaired bladder function, making transient dysfunction less consistent with significant spinal injury 4

Peripheral neuropathy-related bladder dysfunction is less likely:

• Conditions like diabetic cystopathy, Guillain-Barré syndrome, or other peripheral neuropathies can cause bladder dysfunction, but these develop gradually rather than acutely after trauma 5
• The acute onset following a fall makes traumatic etiology more probable than underlying neuropathic disease 5

Clinical Evaluation Framework

Initial Assessment

• Document the fall mechanism, associated injuries, and timeline of bladder dysfunction onset 1
• Perform focused physical examination looking for suprapubic tenderness, perineal/genital ecchymosis, blood at urethral meatus, and pelvic fracture signs 1
• Assess for gross hematuria, which is present in 77-100% of bladder injuries but may be absent in contusions 1
• Evaluate for urinary retention versus incontinence pattern to guide further workup 1, 6

Diagnostic Testing Strategy

• Measure post-void residual (PVR) volume using transabdominal ultrasonography or bladder scanner, repeating 2-3 times due to intra-individual variability 6, 7
• PVR <100 mL indicates normal emptying; 100-200 mL warrants monitoring; >200-300 mL suggests significant dysfunction requiring intervention 6
• Obtain urinalysis to exclude urinary tract infection as a contributing or complicating factor 1, 8
• Perform retrograde cystography (CT or conventional) if there is persistent hematuria, inability to void, suprapubic tenderness, or pelvic fracture to definitively exclude bladder rupture 1

Advanced Evaluation if Symptoms Persist

• Urodynamic studies with cystometry and sphincter electromyography can identify detrusor overactivity, underactivity, or detrusor-sphincter dyssynergia if dysfunction does not resolve 5, 9
• Uroflowmetry analyzes urine flow patterns to suggest obstruction versus impaired contractility 6, 7
• Cystoscopy allows direct visualization if structural abnormality is suspected despite negative imaging 1

Management Approach

For Confirmed Bladder Contusion

• Clinical observation is the primary management, as bladder contusions are self-limited and require no specific treatment 1
• Monitor for resolution of symptoms over days to weeks 1
• Ensure adequate hydration and avoid bladder overdistension during recovery period 3

If Urinary Retention Develops

• Initiate intermittent catheterization every 4-6 hours if PVR >100-200 mL to prevent bladder filling beyond 500 mL 6
• Reassess PVR 4-6 weeks after initiating treatment to document improvement 6
• Consider alpha-blocker therapy if outlet obstruction component is suspected 5

Red Flags Requiring Urgent Intervention

• Persistent gross hematuria suggests more significant injury requiring cystography 1
• Inability to void with suprapubic distension may indicate complete urethral disruption or severe bladder injury 1
• Signs of peritonitis with elevated creatinine could indicate intraperitoneal bladder rupture with urinary ascites 2
• Associated pelvic fracture increases risk of bladder rupture (present in 6-8% of pelvic fractures) and warrants mandatory cystography 1

Common Pitfalls to Avoid

• Do not assume all post-fall bladder dysfunction is benign—always exclude structural injury with appropriate imaging if hematuria or retention persists 1
• Do not rely on passive contrast filling during CT—active retrograde cystography with bladder distension to 350-400 mL is required for accurate diagnosis of bladder rupture 1
• Do not miss intraperitoneal rupture—this requires surgical repair and can cause life-threatening complications if managed conservatively 1
• Do not overlook spinal cord injury—assess for neurological deficits and voluntary anal contraction to predict recovery potential 4
• Do not perform single PVR measurement—repeat 2-3 times due to marked variability to ensure accuracy 6, 7