What are the differential diagnoses for suprapubic tenderness?

Differential Diagnoses for Suprapubic Tenderness

Suprapubic tenderness most commonly indicates bladder pathology—specifically interstitial cystitis/bladder pain syndrome (IC/BPS), urinary tract infection (UTI), or bladder trauma—with the clinical context, associated symptoms, and urinalysis determining which diagnosis is most likely. 1

Primary Urologic Causes

Interstitial Cystitis/Bladder Pain Syndrome (IC/BPS)

• IC/BPS is defined by chronic suprapubic pain and pressure related to bladder filling, accompanied by urinary frequency and urgency without infection, lasting at least 6 weeks. 2, 1
• Patients describe the discomfort as "pressure" rather than sharp pain, which improves after voiding—this distinguishes IC/BPS from UTI where dysuria occurs during urination. 1, 3
• The pain may radiate to the pelvis, urethra, lower abdomen, or back, and patients void primarily to relieve pain rather than to prevent incontinence. 1
• Suprapubic tenderness to palpation is a characteristic physical finding in men with IC/BPS. 4
• Diagnosis requires symptoms persisting more than 6 weeks with negative urine cultures to exclude infection. 2, 1

Urinary Tract Infection (Cystitis)

• Suprapubic tenderness combined with urinary frequency is typical of acute cystitis. 1
• Dysuria provides greater than 90% diagnostic accuracy in young women when vaginal discharge is absent. 1
• Fever, chills, flank pain, and costovertebral angle tenderness indicate pyelonephritis rather than simple cystitis and require different management. 1
• Urinalysis with microscopy and urine culture definitively distinguish UTI from IC/BPS. 1

Bladder Trauma (Intraperitoneal or Extraperitoneal Rupture)

• Bladder injuries occur in approximately 1.6% of blunt abdominal trauma victims, with the vast majority associated with pelvic fractures. 5
• Gross hematuria is present in 77-100% of bladder injuries and should prompt immediate investigation. 5
• Approximately 60% of bladder ruptures are extraperitoneal, 30% are intraperitoneal, and the remainder are combined injuries. 5
• Retrograde cystography (CT or conventional) is critical to determine the presence and type of bladder injury. 5
• Extraperitoneal ruptures are managed non-operatively with catheter drainage, while intraperitoneal ruptures require surgical repair. 5

Chronic Prostatitis/Chronic Pelvic Pain Syndrome (CP/CPPS) in Men

• CP/CPPS causes suprapubic pain that worsens with urination or ejaculation, often accompanied by a sensation of incomplete bladder emptying. 6, 1
• The clinical features of CP/CPPS overlap substantially with IC/BPS, and many male patients meet criteria for both conditions. 6, 7
• Suprapubic tenderness to palpation is a common physical finding. 4
• Digital rectal examination may reveal pelvic floor muscle spasm or anterior rectal wall tenderness. 6, 4

Acute Epididymitis

• Acute epididymitis is characterized by pain, swelling, and elevated temperature of the epididymis, potentially involving the testis and scrotal skin. 5
• In up to 90% of cases, pathogens migrate from the urethra or bladder, with predominant organisms being Enterobacterales, C. trachomatis, and N. gonorrhoeae. 5
• Suprapubic discomfort may occur when bladder involvement is present. 5

Secondary Non-Urologic Causes

Fournier's Gangrene

• Fournier's gangrene presents with painful swelling of the scrotum or perineum with sepsis, though up to 40% of cases have insidious onset with undiagnosed pain. 5
• Suprapubic cystostomy is necessary during surgical debridement for urinary diversion. 5
• CT or MRI helps define pararectal involvement and the need for bowel diversion. 5
• A high index of suspicion is required, particularly in obese, diabetic, or immunocompromised patients. 5

Gastrointestinal Pathology

• Left-sided colonic diverticulitis can mimic urologic pathology with suprapubic or lower abdominal pain. 1
• Inflammatory bowel disease may cause abdominal discomfort that worsens during voiding. 1

Gynecologic Conditions in Women

• Benign adnexal masses and pelvic congestion syndrome can present with lower abdominal and suprapubic pain. 1
• Endometriosis shares symptom overlap with IC/BPS, and many women have both conditions simultaneously. 3

Urethral Injuries

• Blood at the urethral meatus is the most common finding in urethral injuries (present in 37-93%), along with inability to urinate and perineal/genital ecchymosis. 5
• Suprapubic catheter placement is the immediate goal when urethral injury is suspected. 5
• Retrograde urethrography establishes the diagnosis. 5

Critical Diagnostic Algorithm

Initial Evaluation

• Perform urinalysis with microscopy and urine culture first to differentiate UTI from IC/BPS. 1
• Obtain serum beta-hCG in all women of reproductive age before imaging. 1
• Absence of hematuria does not exclude urologic pathology, as more than 20% of patients with urinary stones have negative urinalysis. 1

Imaging Strategy

• Non-contrast CT of the abdomen/pelvis is the gold standard for detecting urinary stones (98-100% sensitivity and specificity) and identifies alternative diagnoses in approximately one-third of cases. 1
• Use ultrasound as first-line imaging in pregnant patients to avoid radiation exposure. 1
• Reserve contrast-enhanced CT for suspected complicated infections (pyelonephritis, perinephric abscess) when fever and systemic symptoms are present. 1

Cystoscopy Indications

• Cystoscopy with hydraulic distention under anesthesia demonstrates severe glomerulations in IC/BPS patients. 4
• Hunner lesions on cystoscopy distinguish ulcerative IC/BPS from non-ulcerative IC/BPS. 2

Key Clinical Pitfalls to Avoid

• Do not automatically attribute suprapubic tenderness with dysuria and frequency to UTI—IC/BPS is frequently misdiagnosed and receives unnecessary antibiotics. 1
• Asymptomatic bacteriuria in older adults should not be treated unless localized urinary symptoms are present. 1
• Duration of catheterization is the leading risk factor for catheter-associated UTI, with prevalence reaching 97.8% at 30 days. 8
• IC/BPS and CP/CPPS may be the same clinical entity in men, with interstitial cystitis, chronic nonbacterial prostatitis, and chronic pelvic pain syndrome sharing identical clinical findings. 4, 7

Red Flags Requiring Urgent Evaluation

• Fever, chills, or systemic signs of infection suggest obstructive pyelonephritis or urosepsis and mandate immediate imaging and possible admission. 1
• Inability to void or markedly reduced urine output indicates complete urinary obstruction requiring urgent intervention. 1
• Hemodynamic instability or shock demands emergent evaluation and management. 1
• Gross hematuria in the setting of trauma requires immediate retrograde cystography to rule out bladder rupture. 5