Treatment of Pyoderma Gangrenosum
Systemic corticosteroids are the first-line treatment for pyoderma gangrenosum, with infliximab as the preferred second-line agent when rapid response to steroids is not achieved. 1
Initial Assessment and Diagnosis
Before initiating treatment, confirm the diagnosis by excluding other conditions, as misdiagnosis occurs in a substantial percentage of cases. 1 Consider biopsy from the periphery of the lesion to rule out infections, vascular disorders, and malignancies, though histopathology findings are non-specific. 1, 2 Identify any underlying systemic disease—particularly inflammatory bowel disease (occurring in 0.6-2.1% of ulcerative colitis patients), hematological malignancies, or rheumatologic disorders—as 50-70% of cases have associated conditions. 2
First-Line Treatment
Systemic corticosteroids are the traditional first-line therapy with the therapeutic goal of rapid healing. 1 The STOP-GAP trial demonstrated that prednisolone achieved 15-20% complete healing at 6 weeks and 47% at 6 months. 3
Topical calcineurin inhibitors (tacrolimus or pimecrolimus) can be used as alternatives or adjuncts, particularly for smaller lesions. 1
Appropriate wound care with modern wound dressings minimizes pain and reduces the risk of secondary infections. 4
Second-Line Treatment
Infliximab should be considered if rapid response to corticosteroids cannot be achieved. 1 Response rates exceed 90% for short-duration pyoderma gangrenosum (<12 weeks) but drop below 50% for longer-standing cases. 1 One RCT showed infliximab was superior to placebo at 2 weeks (46% vs. 6% response) with 21% complete healing at 6 weeks. 3
Adalimumab has demonstrated efficacy in case series and serves as an alternative anti-TNF option. 1 Patients with concurrent inflammatory bowel disease may particularly benefit from biologics. 3
Ciclosporin is equally effective as prednisolone, with the STOP-GAP trial showing similar healing rates (15-20% at 6 weeks, 47% at 6 months). 3
Treatment Algorithm
Confirm diagnosis through clinical presentation, exclusion of other disorders, and identification of underlying disease. 1, 2
Initiate systemic corticosteroids as first-line therapy, adding topical calcineurin inhibitors for smaller lesions. 1
Switch to infliximab if inadequate response to corticosteroids, especially for lesions <12 weeks duration. 1
Consider adalimumab or ciclosporin as alternative second-line agents. 1, 3
Treat underlying systemic disease concurrently, as IBD activity may parallel pyoderma gangrenosum or run an independent course. 2
Special Considerations
Peristomal pyoderma gangrenosum: Closure of the stoma may lead to resolution of lesions in patients with peristomal disease. 1 Trauma triggers lesion development in 20-30% of cases, explaining post-surgical and peristomal occurrences. 2
Combination therapy: Steroids combined with cytotoxic drugs are used in resistant cases, while combinations with sulfa drugs or immunosuppressants serve as steroid-sparing modalities. 4
Critical Pitfalls to Avoid
Do not confuse with ecthyma gangrenosum, which is a cutaneous vasculitis caused by bacterial invasion (classically Pseudomonas aeruginosa) requiring antibiotics, not immunosuppression. 5 Ecthyma gangrenosum presents as painless erythematous papules progressing to painful necrotic lesions within 24 hours, whereas pyoderma gangrenosum is a sterile inflammatory process. 5, 4
Avoid surgical debridement during active disease, as pathergy (lesion development at trauma sites) is a common feature. 6 Surgical intervention should be reserved for after marrow recovery in neutropenic patients or for progressive necrotizing fasciitis. 5
Anticipate high recurrence risk exceeding 25%, often in the same location as the initial episode. 1, 2 Long-term monitoring is essential.
Never use corticosteroids alone without addressing underlying systemic disease, as treatment must target both the skin manifestations and any associated conditions. 2, 6