Overview
Definition:
Explantation of infected prosthetic mesh refers to the surgical removal of a synthetic mesh prosthesis that has become infected following implantation, typically after procedures like hernia repair, abdominal wall reconstruction, or other surgeries requiring reinforcement.
Epidemiology:
Mesh infection is a significant complication, with reported rates varying from 0.3% to 5% depending on the type of surgery, patient factors, and mesh material used
Early infections manifest within weeks to months, while late infections can occur years post-implantation.
Clinical Significance:
Infected mesh is a major cause of morbidity, leading to recurrent infections, chronic pain, wound dehiscence, enterocutaneous fistulas, and the need for extensive surgical intervention
Prompt diagnosis and appropriate management are crucial to prevent severe complications and ensure patient recovery.
Clinical Presentation
Symptoms:
Persistent or recurrent incisional pain
Erythema and swelling at the surgical site
Wound drainage, serous or purulent, sometimes with a foul odor
Fever, chills, and malaise
Palpable fluctuance over the mesh site
Development of a sinus tract or fistula
Constitutional symptoms of sepsis.
Signs:
Localised tenderness and induration
Purulent discharge from the wound
Signs of inflammation: heat, redness, swelling
Dehisced wound edges
Signs of systemic infection: tachycardia, hypotension, tachypnea
Palpable abdominal masses in some cases.
Diagnostic Criteria:
Diagnosis is typically made based on a combination of clinical suspicion, microbiological evidence (wound cultures), and imaging findings
Criteria may include: presence of purulent drainage from surgical site
positive microbial growth from wound aspirate or tissue biopsy
radiographic evidence of abscess or fluid collection around the mesh
and clinical signs of infection unresponsive to antibiotics alone.
Diagnostic Approach
History Taking:
Detailed history of the index surgery: type of procedure, mesh used, antibiotics administered, and any previous complications
Onset and progression of current symptoms
Any history of immunocompromise, diabetes, or obesity
Previous episodes of infection or wound breakdown
Character of wound discharge.
Physical Examination:
Thorough inspection of the surgical incision for signs of inflammation, drainage, and dehiscence
Palpation for tenderness, fluctuance, and induration
Assessment for surrounding erythema or induration
Careful abdominal examination for masses or signs of peritonitis
Evaluation of vital signs for systemic infection.
Investigations:
Complete blood count (CBC) with differential to assess for leukocytosis and elevated inflammatory markers (ESR, CRP)
Blood cultures if sepsis is suspected
Wound cultures (aerobic, anaerobic, fungal) from purulent drainage or tissue biopsy to identify the causative organism and guide antibiotic therapy
Imaging: Ultrasound can detect fluid collections and abscesses
CT scan of the abdomen and pelvis is highly sensitive for identifying mesh infection, abscesses, fistulas, and surrounding tissue involvement
MRI may be useful in specific cases, especially to evaluate soft tissue planes.
Differential Diagnosis:
Seroma formation
Hematoma
Wound dehiscence without infection
Abscess unrelated to mesh
Early graft rejection
Skin and soft tissue infections not involving the mesh
Chronic granuloomatous reaction to foreign material.
Management
Initial Management:
Prompt initiation of broad-spectrum intravenous antibiotics based on local resistance patterns and suspected organisms, pending culture results
Fluid resuscitation and hemodynamic support if signs of sepsis are present
Pain management.
Medical Management:
Antibiotic therapy is crucial but usually not sufficient as a standalone treatment for infected mesh
The choice of antibiotics should be guided by culture and sensitivity results
Duration of therapy is typically prolonged, often for several weeks to months, and may need to be continued even after explantation.
Surgical Management:
Surgical intervention is almost always required for definitive treatment
Indications for explantation include: presence of purulent drainage, abscess formation, sinus tract, fistula, or persistent symptoms despite appropriate antibiotic therapy
The goal is complete removal of the infected mesh
This may involve debridement of infected tissue, drainage of abscesses, and repair of any resulting defects
Often, a staged approach is preferred, with definitive abdominal wall reconstruction performed after resolution of infection, sometimes using biologic meshes or autologous tissue.
Supportive Care:
Aggressive wound care, including regular dressing changes and potential use of negative pressure wound therapy (NPWT) to manage complex wounds and promote granulation
Nutritional support, particularly for patients with significant protein loss or malabsorption
Close monitoring for signs of recurrent infection or complications.
Complications
Early Complications:
Wound dehiscence
Persistent or recurrent infection
Abscess formation
Sepsis
Injury to adjacent organs (bowel, bladder)
Hemorrhage.
Late Complications:
Chronic pain syndrome
Incisional hernia recurrence
Formation of enterocutaneous fistulas
Adhesions and bowel obstruction
Development of a sinus tract requiring prolonged management
Psychological distress and impact on quality of life.
Prevention Strategies:
Judicious use of prosthetic mesh
Strict aseptic techniques during mesh implantation
Appropriate antibiotic prophylaxis
Proper patient selection and risk factor modification (e.g., weight loss, diabetes control)
Careful surgical technique to minimize tissue trauma and dead space
Early recognition and management of superficial wound complications.
Prognosis
Factors Affecting Prognosis:
The virulence of the infecting organism
The extent of infection and tissue involvement
The patient's overall health status and immune response
The success of surgical explantation and debridement
Whether a staged approach to reconstruction is used
Presence of comorbidities like diabetes, obesity, or malnutrition.
Outcomes:
With timely and aggressive management, including surgical explantation and appropriate antibiotics, most patients can achieve resolution of infection
However, recurrence is possible
The need for subsequent abdominal wall reconstruction can lead to prolonged recovery and potential functional deficits
Chronic pain can persist in a subset of patients.
Follow Up:
Long-term follow-up is essential
This includes monitoring for signs of recurrent infection, incisional hernia, and wound healing
Imaging studies may be required periodically
Patients should be educated on self-monitoring for early signs of recurrence
Multidisciplinary care involving surgery, infectious diseases, and physical therapy may be beneficial.
Key Points
Exam Focus:
Infected mesh is a surgical emergency requiring prompt diagnosis and aggressive management
CT scan is the imaging modality of choice for evaluation
Complete surgical explantation is usually necessary
Staged reconstruction is often preferred
Antibiotics alone are insufficient for definitive treatment.
Clinical Pearls:
Always suspect mesh infection in patients with persistent, non-resolving wound drainage or pain following mesh implantation
Consider polymicrobial infections and the role of biofilm
The goal of surgery is complete removal of all foreign material and infected tissue
Early consultation with infectious disease specialists is highly recommended.
Common Mistakes:
Delaying surgical intervention in favor of prolonged antibiotic therapy
Incomplete mesh removal, leading to persistent infection
Failure to obtain appropriate cultures before starting antibiotics
Underestimating the complexity of wound management and reconstruction post-explantation
Not considering the possibility of infection in late-presenting symptoms.