Urethrocutaneous Fistula: Symptoms, Types, Causes and Treatment

Urethrocutaneous fistula (UCF) is a distressing urological condition where an abnormal tract forms between the urethra and the skin. This can result in urine leaking through the skin, typically at the penis or perineum, instead of exiting solely through the normal urinary channel. UCF can affect individuals of all ages but is most commonly seen in children following penile surgery, such as hypospadias repair or circumcision. Beyond the physical symptoms, the condition often brings significant emotional and social challenges. In this comprehensive article, we explore the symptoms, types, causes, and modern treatments of urethrocutaneous fistula, drawing on the latest clinical evidence for clarity and guidance.

Symptoms of Urethrocutaneous Fistula

Recognizing the symptoms of urethrocutaneous fistula is essential for prompt diagnosis and successful treatment. While the hallmark sign is abnormal passage of urine through the skin, other associated symptoms may affect quality of life and prompt medical attention.

Symptom	Description	Impact	Source(s)
Urine leakage	Urine exits through skin opening	Hygiene, skin irritation	6, 7
Recurrent infections	Repeat urinary tract or wound infections	Risk of complications	5, 6
Local pain	Discomfort or pain at fistula site	Affects daily activities	7
Incontinence	Loss of urinary control	Social, emotional distress	7, 6

Table 1: Key Symptoms

The Hallmark Symptom: Urine Leakage

The most prominent and defining symptom of UCF is the leakage of urine through an abnormal opening on the penis or perineum. This leakage may occur continuously or only during urination, depending on the size and location of the fistula. The presence of urine on the skin can cause persistent wetness, foul odor, and skin irritation, leading to discomfort and social embarrassment, especially in children and adolescents 6, 7.

Associated Symptoms: Infection and Pain

The abnormal tract can be a source of recurrent infections, both at the skin level and in the urinary tract. The constant exposure of skin to urine creates a moist environment, ideal for bacterial growth, increasing the risk of wound infection and potentially leading to cellulitis or abscess formation 5, 6. Pain or tenderness around the fistula, especially during urination, may signal infection or inflammation.

Incontinence and Psychosocial Impact

Some patients, particularly those with larger or more proximal fistulas, experience varying degrees of urinary incontinence. This can result in involuntary loss of urine, causing distress, embarrassment, and withdrawal from social activities. Children may become reluctant to attend school or participate in sports, and adults may avoid intimate relationships or public events 7, 6. These psychosocial effects are often under-recognized yet play a significant role in a patient’s well-being.

Types of Urethrocutaneous Fistula

Urethrocutaneous fistulae are classified in several ways: by location, cause, and whether they are congenital or acquired. Understanding these types helps guide both diagnosis and management.

Type	Typical Location	Common Context	Source(s)
Subcoronal	Near the glans (subcoronal)	Post-circumcision, congenital	1, 2, 6
Penile shaft	Along penile body	Post-surgery (hypospadias)	3, 5, 6
Penoscrotal	At penoscrotal junction	Proximal hypospadias repair	8, 6
Perineal	Perineum	Rare, congenital or traumatic	6, 7

Table 2: Classification by Type

Location-Based Classification

• Subcoronal Fistula: Most frequently found just below the head of the penis, especially following circumcision or as a congenital defect. This is the most common site in children and accounts for nearly half of congenital anterior UCF cases 1, 2, 6.
• Penile Shaft Fistula: Occurs anywhere along the penile shaft, often as a complication of hypospadias repair surgery 3, 5, 6.
• Penoscrotal and Perineal Fistula: These are less common but occur in cases of more severe hypospadias or perineal trauma, or rarely as isolated congenital anomalies 6, 8.

Cause-Based Classification

• Congenital Urethrocutaneous Fistula: Present at birth, typically isolated but may be associated with other genitourinary or anorectal malformations. Congenital anterior UCF most frequently presents subcoronally 2.
• Acquired Urethrocutaneous Fistula: These develop due to trauma, surgery (particularly hypospadias repair or circumcision), infection, or foreign body insertion 1, 3, 5, 6, 7.

Single vs. Multiple Fistulae

Most urethrocutaneous fistulas are solitary, but multiple tracts can occur, especially after previous surgeries or in complex cases 8. Treating multiple fistulae can be more challenging and may require specialized surgical techniques.

Causes of Urethrocutaneous Fistula

The development of urethrocutaneous fistula is multifactorial, with both iatrogenic (surgery-related) and non-iatrogenic causes. Understanding these causes is crucial for prevention and tailored treatment.

Cause	Description	Risk Factors	Source(s)
Surgical Complication	Most commonly after hypospadias/circumcision	Poor technique, infection, tension	1, 3, 5, 6, 8
Congenital Anomaly	Present at birth, rare	May have associated anomalies	2, 6
Trauma/Foreign Body	Injury or objects inserted in urethra	Adolescents, self-injury	7, 6
Infection	Infection after surgery or trauma	Wound infection, meatal stenosis	5, 6

Table 3: Main Causes

Surgical Complications

• Hypospadias Repair: The most frequent cause of UCF is as a complication of hypospadias repair, with rates ranging from 4% to 47% depending on the series and surgical technique 3, 5, 6, 8.
  • Risk factors include: posterior or proximal hypospadias, longer urethral defect, lack of an intermediate tissue layer between neourethra and skin, wound infection, and meatal stenosis 3, 5, 8.
• Circumcision: Particularly in children, UCF may arise from poorly performed circumcisions, especially when done by non-specialists or in resource-limited settings 1, 6.

Congenital Urethrocutaneous Fistula

• These are rare but usually present at birth as an isolated penile fistula, often subcoronal, but can occur elsewhere. Sometimes, they are associated with other anomalies like chordee (penile curvature) or anorectal malformations 2, 6.

Trauma and Foreign Bodies

• UCF may result from penile or perineal trauma, including accidental injury or self-insertion of foreign bodies into the urethra. Such cases are rare but have been reported, especially in adolescents 7.

Infection

• Postoperative or post-traumatic wound infections significantly increase the risk of fistula formation. Meatal stenosis (narrowing of the urethral opening) can also predispose to fistula development through increased pressure and poor wound healing 5, 6.

Other Contributing Factors

• Preoperative Pyuria: Presence of white blood cells in the urine before surgery is a significant risk factor for fistula formation after hypospadias repair 3.
• Hemoglobinopathies: Some studies suggest that children with abnormal hemoglobin types may have an increased risk of developing UCF, possibly due to impaired wound healing 6.

Treatment of Urethrocutaneous Fistula

Treating UCF aims for complete closure of the fistula, restoration of normal urinary function, and prevention of recurrence. Treatment is often surgical but depends on the size, location, and cause of the fistula, as well as patient factors.

Treatment	Approach/Technique	Indication	Source(s)
Simple Closure	Direct suture, possibly multilayer	Small, first-time fistula	6, 10, 11
Flap Repair	Dartos, tunica vaginalis, skin flap	Recurrent or large fistula	1, 8, 9, 12
Tissue Substitutes	Integra®, dCELL (biomaterials)	Multiple prior surgeries, limited tissue	9, 12
Conservative	Allow spontaneous closure	Small, low-output, early	2, 7

Table 4: Treatment Options

Surgical Repair: The Mainstay

• Simple Closure: For small, isolated, and first-time fistulas (≤2 mm), direct multilayer closure or ligation is often successful. Techniques like the use of a longitudinal relaxing incision can reduce tension and recurrence 10, 11. Most post-circumcision fistulas respond well to this approach 6.
• Flap-Based Techniques: In larger, recurrent, or complex fistulas, tissue flaps provide a vascularized layer between the urethra and skin, reducing recurrence. Options include:
  • Dartos Flap: Commonly used, especially after hypospadias surgery.
  • Tunica Vaginalis Flap: Shown to have a lower recurrence rate and effective for multiple or anterior fistulas; can be particularly useful when dartos tissue is unavailable or previously used 8.
  • Penile Skin or Mathieu Flap: Useful for specific distal shaft or subcoronal fistulas 1.
• Tissue Substitutes: In patients with multiple failed repairs or lacking local tissue, biomaterials like Integra® (bovine dermal matrix) or decellularized human dermis (dCELL) provide alternative coverage and reduce overlapping suture lines 9, 12.

Conservative and Non-Surgical Approaches

• Observation: Small, low-output fistulas may close spontaneously, especially in congenital cases or after removal of the offending cause (e.g., foreign body) 2, 7.
• Infection Control: Treating infections promptly, both pre- and postoperatively, is essential to reduce recurrence risk 5, 6.

Factors Influencing Surgical Success

• Intermediate Layer: Placing a protective tissue layer (like dartos or tunica vaginalis) between the neourethra and skin is crucial for preventing recurrence 8, 12.
• Preoperative Optimization: Screening for infection (pyuria) and correcting it before surgery improves outcomes 3.
• Technique Selection: Surgical technique should be individualized based on the patient’s anatomy, prior surgeries, and tissue availability 1, 8, 9.

Recurrence and Management

• Recurrence rates vary by technique and patient factors but can be significant, especially after hypospadias surgery 5, 6. Repeat surgical repair using flap techniques or biomaterials usually offers good outcomes. Multilayer closure and tension-free repair are key principles 11.

Conclusion

Urethrocutaneous fistula is a challenging condition, most commonly arising as a complication of penile surgery in children but also seen due to congenital anomalies, trauma, or infection. The key points to remember include:

• Symptoms: Characterized primarily by abnormal urine leakage through the skin, often accompanied by infection, pain, and social distress 6, 7.
• Types: Classified by location (subcoronal, penile, penoscrotal, perineal) and etiology (congenital vs. acquired) 1, 2, 3, 6.
• Causes: Most frequently surgical (hypospadias, circumcision), but can also be congenital, traumatic, or infectious. Risk factors include infection, poor surgical technique, lack of tissue interposition, and preoperative pyuria 3, 5, 6, 8.
• Treatment: Ranges from conservative management for small or early fistulas to multilayer surgical repair using local flaps or biomaterials for complex or recurrent cases. Ensuring an intermediate tissue layer and minimizing tension are critical for success 8, 9, 10, 11, 12.

Summary of Main Points:

• UCF presents with abnormal urine passage, risking infection and psychosocial distress.
• Most cases result from surgical complications, but congenital and traumatic causes exist.
• Classification by location and cause guides treatment decisions.
• Modern surgical techniques, especially those using tissue flaps or biomaterials, have significantly improved repair success, but recurrence remains a challenge in complex cases.
• Prevention includes meticulous surgical technique, infection control, and patient-specific planning.

Understanding the spectrum of urethrocutaneous fistula helps clinicians, patients, and families make informed decisions on management and sets the stage for ongoing advancements in surgical care and patient outcomes.