Abstract and Introduction
Pyoderma gangrenosum (PG) is an uncommon inflammatory neutrophilic disorder with a spectrum of clinical presentations with variable courses. Most cases are associated with an autoimmune disorder and manifest in middle-aged adults as a painful lesion that progresses to painful necrotizing ulcers of the lower extremity. Owing to its variability, clinical diagnosis remains difficult and many patients are often misdiagnosed, with resulting delay in treatment. While early immunosuppressant therapy is key to preventing progression of PG, surgical treatment has been met with criticism because of the risk of potentiating pathergy, an exaggerated skin reaction due to trauma. This article presents a case series in which 3 patients with PG lesions underwent different treatment methods, including surgical debridement and use of fetal bovine dermis (FBD). The use of FBD in conjunction with medical treatment provided pain relief and wound coverage as well as encouraged growth of granulation tissue and long-term stability. Commercial cellular and tissue-based products used to aid in accelerating PG wound closure are also reviewed.
Pyoderma gangrenosum (PG) is a rare inflammatory neutrophilic disorder that causes progressive ulcers as part of an autoimmune disease process. The clinical presentation is variable, although typically it is characterized by skin lesions that progress to painful necrotizing ulcerations with blue-hued purpuric undermined edges and skin sloughing (Figure 1A). The most commonly affected site is the lower extremity, with solitary ulcerations or a disseminated presentation; however, PG may also involve the head, neck, and perianal area that are more often found in infants and children.[1–3] Other recognized variants of PG are bullous, pustular, vegetative, peristomal, extracutaneous, and postsurgical, but ulcerative PG remains the most common type.
Case 1: Photographic temporal evolution of pyoderma gangrenosum on the right lower extremity. Wound is shown (A) at presentation, (B) 4 days after fetal bovine dermis (FBD) application, (C) 7 days after FBD, (D) 1 month following FBD.
Pyoderma gangrenosum affects individuals of all ages, with a peak incidence in young to middle-aged adults; PG has no sex predilection.[1,4,5] It has been associated with underlying diseases in up to 75% of cases. The most common underlying diseases associated with PG are inflammatory bowel disease (IBD) (34%–65%), polyarthritis (16%–19%), and hematologic disorders (12%–20%). Because PG is associated with systemic autoimmune diseases, its pathogenesis is believed to be immunologic.[1,5]
The diagnosis of PG is made based on clinical judgment and by exclusion because no specific diagnostic criteria exist. Research suggests biopsy can aid in the diagnosis if neutrophilic infiltration of the dermis and skin is seen on pathologic examination. However, a false-negative biopsy result is possible; alternatively, biopsy may potentiate an exaggerated skin injury and rapid progressive ulcerations of the wound. This characteristic phenomenon is called pathergy, which can occur after minor injury to the skin via surgery, trauma, biopsy, and even venipuncture.[1–6]
Surgical interventions such as radical debridement with full-thickness skin graft, split-thickness skin graft (STSG), and even free flaps have been reported in the literature as potential therapy for extensive PG wounds that require coverage.[6–8] Concurrent medical immunosuppressive therapy to control the inflammatory response is also vital to avoid the need for surgery, because surgical intervention can trigger pathergy and disease progression.[1,2,4–7,9]
This case series and literature review provides an overview of surgical treatments and the application of cellular- and/or tissue-based products (CTPs) for PG. Literature was identified based on English-language key word search in PubMed using the key words "pyoderma gangrenosum", "skin graft", and "skin substitute"; in addition, the commercial names of 72 commercially available CTPs are included.
Wounds. 2021;33(6):161-168. © 2021 HMP Communications, LLC