Excision of Pyoderma Gangrenosum: Contraindicated
Surgical excision of pyoderma gangrenosum is contraindicated and should be avoided during active disease, as it will trigger pathergy—the phenomenon where trauma to the skin causes new or worsening lesions at the site of injury. 1
Why Excision is Harmful
Pathergy Response
- Pathergy is a defining feature of pyoderma gangrenosum where any form of trauma, including surgical intervention, triggers development or extension of lesions at the trauma site 2
- Surgical debridement during active disease will worsen the condition rather than improve it, as the inflammatory process is sterile and not infectious 1
- Even routine surgical procedures can trigger dramatic presentations of pyoderma gangrenosum, as documented in cases where minor anorectal surgery led to extensive perianal disease 3
Misdiagnosis Risk
- Pyoderma gangrenosum is frequently misdiagnosed as wound infection in the post-surgical setting, leading to inappropriate surgical debridement that worsens outcomes 3
- The condition mimics infection with purulent material in ulcerations, but this material is sterile unless secondary infection has occurred 4
- Misdiagnosis occurs in a substantial percentage of cases due to variable presentation 4
The Correct Treatment Approach
First-Line Medical Management
- Systemic corticosteroids (100-200 mg/day prednisone initially) are the first-line treatment with the goal of rapid healing 1, 5
- Topical calcineurin inhibitors (tacrolimus or pimecrolimus) can be used for smaller lesions 1
Second-Line Options
- Infliximab should be initiated if rapid response to corticosteroids is not achieved, with response rates exceeding 90% for lesions present less than 12 weeks but dropping below 50% for longer-standing cases 1
- Adalimumab serves as an alternative anti-TNF option 1
- Cyclosporine is effective as maintenance treatment 5
When Surgery May Be Considered
Only After Disease Control
- Reconstructive surgery may be beneficial only after the systemic inflammatory response is adequately controlled with immunosuppressive therapy 6
- With adequate systemic treatment, the benefits of reconstructive surgery for wound management are increasing 6
- Skin transplants (split-skin grafts or autologous keratinocyte grafts) are useful in selected cases in conjunction with immunosuppression, not as standalone treatment 5
Special Circumstance: Peristomal Disease
- For peristomal pyoderma gangrenosum specifically, closure of the stoma may lead to resolution of lesions 1
- This represents a unique situation where surgical intervention (stoma closure) addresses the underlying trigger rather than the lesions themselves 4
Critical Pitfalls to Avoid
- Do not mistake pyoderma gangrenosum for wound infection requiring debridement—the characteristic rapidly progressing painful ulcers with undermined violaceous borders and purulent material that fails to improve with antibiotics should raise suspicion 3
- Do not perform surgical debridement when lesions show minimal improvement with antibiotic treatment—this suggests pyoderma gangrenosum rather than infection 3
- Distinguish from ecthyma gangrenosum (bacterial cutaneous vasculitis) which requires antibiotics, not immunosuppression; ecthyma presents as painless erythematous papules progressing to necrotic lesions within 24 hours, whereas pyoderma gangrenosum is a sterile inflammatory process 1
Underlying Disease Management
- Screen for associated systemic diseases in 50-70% of cases, most commonly inflammatory bowel disease (0.6-2.1% of ulcerative colitis patients), rheumatological disorders, hematological disease, or malignancy 4, 7, 2
- Treatment of underlying disease is essential for successful management 2
- Recurrence occurs in more than 25% of cases, often at the same location 1