Residency · Residency · Urology
Urologic Emergencies: Testicular Torsion and Fournier Gangrene
Introduction
Testicular torsion and Fournier gangrene are among the most urgent emergencies encountered in urology, requiring rapid diagnosis and intervention to prevent severe morbidity and mortality. Testicular torsion demands immediate scrotal exploration and detorsion to salvage the affected testis, as the window for viability is narrow. Fournier gangrene, a necrotizing fasciitis of the perineum and genitalia, carries a mortality rate of 20-40% and necessitates prompt surgical debridement combined with broad-spectrum antibiotics. Both conditions highlight the critical importance of swift recognition and decisive treatment.
Testicular Torsion
Pathophysiology
Testicular torsion occurs when the spermatic cord twists, compromising blood flow to the testis. The most common form, intravaginal torsion, accounts for 90% of cases and involves twisting of the spermatic cord within the tunica vaginalis. This is typically caused by a "bell-clapper" deformity, where the tunica vaginalis attaches abnormally high on the spermatic cord, allowing the testis to rotate freely. In contrast, extravaginal torsion occurs primarily in neonates, where the entire testis, tunica vaginalis, and spermatic cord twist together due to unfixed gubernacular attachments. The twisting initially obstructs venous drainage, leading to congestion, and subsequently compromises arterial inflow, resulting in hemorrhagic infarction of the testis.
Epidemiology
Intravaginal torsion most commonly affects males aged 12 to 18 years, while extravaginal torsion is seen in the neonatal period. The annual incidence of testicular torsion is approximately 1 in 4,000 males under 25 years of age. The bell-clapper deformity is bilateral in 80% of cases, which necessitates contralateral orchiopexy during surgical management to prevent future torsion. Torsion tends to occur slightly more often on the left side than the right.
Clinical Presentation
Patients with testicular torsion typically present with sudden, severe unilateral testicular pain that often awakens them from sleep. Nausea and vomiting accompany the pain in up to half of cases. A key physical exam finding is the absence of the cremasteric reflex, which has a sensitivity of 99% for torsion when absent. On examination, the affected testis is often high-riding with a transverse lie. The Prehn sign, which involves relief of pain upon scrotal elevation, is negative in torsion, distinguishing it from epididymitis. The duration of symptoms is critical in determining the likelihood of salvaging the testis.
Testicular Salvage Rates by Duration
The probability of saving the testis decreases sharply with time. If detorsion occurs within six hours of symptom onset, the salvage rate is 90-100%. Between six and twelve hours, salvage drops to about 50%, and between twelve and twenty-four hours, it falls further to 10-20%. Beyond twenty-four hours, the salvage rate approaches zero. This six-hour window is the critical benchmark, and surgical exploration should not be delayed for imaging if clinical suspicion is high.
| Duration of Symptoms | Testicular Salvage Rate |
|---|---|
| <6 hours | 90-100% |
| 6-12 hours | ~50% |
| 12-24 hours | 10-20% |
| >24 hours | Near 0% |
Diagnosis
Testicular torsion is primarily a clinical diagnosis. When suspicion is strong, immediate surgical exploration is warranted without waiting for imaging. However, if the diagnosis is uncertain, color Doppler ultrasound can be used to assess blood flow. Ultrasound typically shows absent or decreased intratesticular blood flow on the affected side, with sensitivity ranging from 88 to 100% and specificity from 90 to 100%. A specific ultrasound finding is the "whirlpool sign," which depicts a spiral pattern of the twisted spermatic cord. Despite its utility, ultrasound should never delay surgery when clinical suspicion is high. The differential diagnosis includes epididymitis, torsion of the testicular appendage (appendix testis), incarcerated inguinal hernia, scrotal abscess, and testicular tumor with hemorrhage.
Surgical Management
Surgical management involves scrotal exploration through either a midline raphe or transverse scrotal incision. The testis is detorsed by untwisting the spermatic cord, which typically twists medially to laterally; this is often described as a "book-opening" maneuver. After detorsion, the testis is assessed for viability by observing color changes and is wrapped in warm saline-soaked gauze for 10 to 15 minutes. If viable, bilateral orchiopexy is performed by fixing both testes to the dartos fascia with non-absorbable sutures at three or more points to prevent recurrence, given the bilateral nature of the bell-clapper deformity. If the testis is non-viable, orchiectomy is performed on the affected side, along with contralateral orchiopexy. Manual detorsion can be attempted at the bedside as a temporizing measure by rotating the testis outward (lateral to medial, "opening the book"), which provides pain relief in 30-70% of cases but still requires subsequent surgical exploration.
<image>Surgical illustration showing: (1) bell-clapper deformity with high attachment of tunica vaginalis allowing free rotation of the testis, (2) 720-degree intravaginal torsion of the spermatic cord with venous congestion and hemorrhagic discoloration of the testis, (3) detorsion and testis showing color recovery, and (4) bilateral orchiopexy technique with non-absorbable sutures fixing the testis to the dartos fascia in three points</image>
Neonatal Torsion
Extravaginal torsion in neonates occurs prenatally or perinatally and presents as a painless, firm, discolored scrotal mass at birth. Bilateral neonatal torsion constitutes a surgical emergency due to the risk of anorchia. Management remains controversial; some advocate urgent exploration for bilateral cases, while observation may be reasonable for unilateral cases with a clearly non-viable testis. Contralateral orchiopexy is generally recommended to prevent future torsion.
Torsion of the Appendix Testis
Torsion of the appendix testis or appendix epididymis involves twisting of vestigial Mullerian duct remnants. It most commonly affects boys aged 7 to 12 years and is more frequent than testicular torsion in prepubertal boys. The pathognomonic "blue dot sign," visible through the scrotal skin at the upper pole of the testis, aids diagnosis. Unlike testicular torsion, the cremasteric reflex remains intact, and tenderness is localized to the upper pole. Management is conservative, involving NSAIDs, scrotal support, and activity restriction for five to seven days. Surgical exploration is reserved for uncertain diagnoses, as clinical distinction from testicular torsion can be challenging.
Fournier Gangrene
Definition and Pathophysiology
Fournier gangrene is a necrotizing fasciitis affecting the perineum, scrotum, and/or penis, with potential extension to the abdominal wall, thighs, and retroperitoneum. It is a polymicrobial infection involving aerobic bacteria such as Escherichia coli, Klebsiella, Streptococcus, and Staphylococcus species, alongside anaerobic organisms including Bacteroides, Clostridium, and Peptostreptococcus. These organisms act synergistically to cause obliterative endarteritis of subcutaneous vessels, leading to tissue ischemia and rapid fascial necrosis. Gas-producing bacteria cause crepitus, which can be palpated in affected tissues. The infection spreads along fascial planes including Colles' fascia in the perineum, dartos fascia in the scrotum, and Scarpa's fascia in the anterior abdominal wall. Notably, the testes are typically spared due to their independent blood supply from the testicular artery, which originates retroperitoneally and does not rely on scrotal vasculature.
Risk Factors
The most significant risk factor for Fournier gangrene is diabetes mellitus, present in 40-60% of cases. Other predisposing factors include immunosuppression from HIV, chronic steroid use, chemotherapy, or transplant status, as well as obesity, poor hygiene, chronic alcoholism, and liver disease. Common sources of infection include perianal abscesses (30-50%), urogenital infections (20-40%), skin or soft tissue infections, and postoperative wounds.
Clinical Presentation
Patients typically experience pain that is out of proportion to physical findings early in the disease course. Rapidly progressive erythema, edema, and induration of the perineal and scrotal skin follow. Crepitus on palpation, indicating gas in the subcutaneous tissues, is present in 50-62% of cases. Systemic toxicity manifests as high fever, tachycardia, hypotension, and altered mental status. As the infection advances, skin necrosis develops with dusky or gangrenous patches and foul-smelling wound discharge. Without prompt treatment, the condition can rapidly progress to septic shock and multiorgan failure.
Diagnosis
Fournier gangrene is primarily a clinical diagnosis, and surgical debridement should not be delayed for imaging when the diagnosis is evident. If uncertainty exists, computed tomography (CT) can identify subcutaneous gas, fascial thickening, fat stranding, and fluid collections, helping to delineate the extent of disease. Laboratory findings typically include leukocytosis often exceeding 20,000 cells/mm³, elevated lactate, metabolic acidosis, elevated creatinine, and hyponatremia. The Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) score incorporates C-reactive protein, white blood cell count, hemoglobin, sodium, creatinine, and glucose levels; a score greater than six suggests necrotizing fasciitis with a sensitivity of 68-92%.
<image>Clinical progression photographs of Fournier gangrene showing: (1) early stage with perineal erythema and edema with pain out of proportion to findings, (2) intermediate stage with scrotal skin necrosis, crepitus markings, and extension to inguinal region, and (3) post-debridement wound with viable testes exposed after removal of all necrotic fascia and skin, demonstrating the extent of surgical debridement required</image>
Management
Immediate Resuscitation
Management begins with aggressive intravenous fluid resuscitation and hemodynamic stabilization. Broad-spectrum antibiotic therapy is essential and typically includes triple therapy: vancomycin or linezolid for MRSA coverage, combined with piperacillin-tazobactam or a carbapenem for broad aerobic and anaerobic coverage, and clindamycin to suppress toxin production and anaerobic bacteria. Correction of coagulopathy, electrolyte imbalances, and hyperglycemia is critical. Patients often require intensive care unit admission for close hemodynamic monitoring.
Surgical Debridement
Emergency surgical debridement is the cornerstone of treatment, as delays significantly increase mortality. Radical excision of all necrotic tissue is performed until healthy, bleeding tissue margins are reached. Multiple planned return trips to the operating room every 24 to 48 hours are common for reassessment and additional debridement, with an average of three to four procedures typically required. Fecal diversion via loop colostomy may be necessary when the perianal source is involved or when extensive perianal involvement impedes wound care. A suprapubic catheter may be placed if urethral involvement precludes transurethral catheterization.
Wound Management and Reconstruction
Negative pressure wound therapy using wound VAC devices accelerates granulation tissue formation and serves as a bridge to definitive closure. Once the wound bed is clean and granulating, split-thickness skin grafts are applied. Scrotal reconstruction can be achieved through medial thigh advancement flaps or primary closure using scrotal skin remnants. When scrotal skin is completely lost, the testes may be temporarily placed in thigh pouches for protection.
Prognosis
Mortality from Fournier gangrene ranges from 20 to 40%, with higher rates associated with delayed debridement, extensive disease, and comorbid conditions. The Fournier Gangrene Severity Index (FGSI), which incorporates vital signs and laboratory values, predicts outcomes; scores above nine correlate with a 75% mortality rate. Early surgical debridement within 24 hours of admission significantly improves survival.
<image>CT scan of the pelvis in a patient with Fournier gangrene showing extensive subcutaneous emphysema (gas tracking) in the scrotum, perineum, and bilateral inguinal regions, fascial thickening with inflammatory stranding, and bilateral scrotal wall thickening, with annotations labeling the gas collections and fascial planes involved</image>
Key Clinical Pearls
In testicular torsion, the absence of the cremasteric reflex is the most sensitive physical exam finding, and exploration should not be delayed for ultrasound if clinical suspicion is high. The critical six-hour window for testicular salvage underscores the urgency of intervention, and bilateral orchiopexy is essential since the bell-clapper deformity is bilateral in 80% of cases. For Fournier gangrene, pain out of proportion to physical findings is an early hallmark, especially in diabetic and immunocompromised patients, and maintaining a high index of suspicion is vital. Surgical debridement within 24 hours is the single most important factor in reducing mortality. Importantly, the testes are typically spared in Fournier gangrene due to their independent blood supply.
References
- Sharp VJ, Kieran K, Arlen AM. Testicular torsion: diagnosis, evaluation, and management. Am Fam Physician. 2013;88(12):835-840.
- Eke N. Fournier's gangrene: a review of 1726 cases. Br J Surg. 2000;87(6):718-728.
- Sorensen MD, Krieger JN, Rivara FP, et al. Fournier's gangrene: population based epidemiology and outcomes. J Urol. 2009;181(5):2120-2126.
- Laor E, Palmer LS, Tolia BM, et al. Outcome prediction in patients with Fournier's gangrene. J Urol. 1995;154(1):89-92.
