Postoperative pyoderma gangrenosum after gunshot wound: A case report

Pyoderma gangrenosum (PG) is a rare neutrophilic dermatosis of unclear etiology that exhibits pathergy and can develop post-operatively in surgical incisions. To the best of our knowledge, this is the first case report of PG developing after a gunshot wound (GSW) injury or in a contaminated surgical wound. We further propose umbilical sparing as a key clinical finding differentiating the diagnosis of PG from more common infectious etiologies.

Infection mimicking skin condition: pyoderma gangrenosum

The a priori risk of infection is high when a patient presents with an ulcerative skin condition and elevated inflammatory parameters. If the ulceration is progressive despite adequate antibiotic therapy and tissue cultures are negative, pyoderma gangrenosum should be considered as the diagnosis. This rare infection mimicking skin condition can develop and worsen due to surgery. In this paper, we report two cases that illustrate the importance of making this clinical diagnosis in a timely manner in order to avoid unnecessary surgical interventions and worsening of the clinical picture.

A Case Report of Necrotizing Neutrophilic Dermatosis: A Sheep in Wolf’s Clothing

Neutrophilic dermatosis (ND) is a category of diseases characterized by trauma-induced, autoinflammatory cutaneous eruption. Comorbid systemic disease is common with a predilection for malignancy, inflammatory bowel disease, and rheumatologic disease. Rarely, it can manifest with aseptic shock, an entity referred to as necrotizing neutrophilic dermatosis (NND). NND may occur in the postoperative setting and is often misdiagnosed as a necrotizing soft tissue infection. Unfortunately, the treatment for a necrotizing soft tissue infection, namely, wide debridement, is often detrimental in the setting of NND. We present the case of a woman with underlying myelodysplastic syndrome who developed episodic postoperative hemodynamic collapse followed by delayed necrotic peristomal ulceration following colonic diversion for complicated diverticulitis. Infectious workup and operative re-exploration were unrevealing. Pathologic assessment of affected skin tissue showed changes consistent with ND, ultimately leading to the diagnosis of NND. Her clinical course dramatically improved with the initiation of immunosuppressive therapy. The mimicry of NND to a potentially lethal necrotizing soft-tissue infection creates a grave diagnostic dilemma in the postoperative period. A general lack of knowledge of NND among non-dermatologic specialists produces an opportunity for misdiagnosis and inappropriate surgical interventions, namely, serial debridement. Several clinical cues may aid in the earlier recognition of NND. The cornerstone of treatment involves systemic corticosteroid therapy with adjunctive therapy for refractory cases. NND must be considered in the differential diagnosis of necrotizing soft tissue infection as early recognition may result in the avoidance of deleterious surgical interventions.

Gap of knowledge in diagnosis of pyoderma gangrenosum in clinical specialties education

OBJECTIVES

Pyoderma gangrenosum (PG) is a chronic ulcerative neutrophilic dermatosis. It presents a diagnostic challenge due to the absence of disease-specific markers or histopathology, lack of universally accepted diagnostic criteria, and many mimicking diseases including necrotizing soft tissue infections (NSTI). PG cases often present first to specialties other than dermatology. We reviewed major educational resources in internal medicine, family medicine, and infectious disease for their coverage of PG.

CONTENT

For each specialty, we reviewed five major textbooks, five prominent journals, and any commonly used online resources. Twelve of 15 textbooks mentioned PG, only three of which included a differential, with none including NSTI in the differential. Only two of 13 journals included review articles about PG, and none of these including NSTI in their differential. Interestingly, online resources tended to be the most complete; six of nine contained PG articles, nearly all including a differential and three listing NSTI within it.

SUMMARY

We found an underrepresentation of PG among major textbooks and journals in clinical specialties, especially in differentiating PG from its mimickers. While online resources may help fill this gap in knowledge, texts and journals remain essential. Misdiagnosis and resultant mismanagement of PG can lead to disastrous outcomes.

OUTLOOK

We recommend that PG be added to the differential diagnoses of chronic ulcers in educational resources. We also suggest the addition of identification and differentiation of PG to learning materials and lectures for providers in specialties who may encounter PG, NSTI, or similarly presenting diseases to address this gap.