Background: Pyoderma gangrenosum (PG) is a rare, immune-mediated neutrophilic dermatosis characterized by painful, rapidly progressive ulceration and a propensity for pathergy. Diagnosis is clinical and often complicated by nonspecific or evolving histopathologic findings that may overlap with other neutrophilic or granulomatous dermatoses. Case Presentation: We report a 63-year-old woman with ulcerative colitis who developed extensive, multifocal ulcerations involving peristomal skin, trunk, breast, face, and genital region following colectomy. Early biopsies demonstrated a palisaded neutrophilic and granulomatous dermatitis–like pattern, while subsequent biopsies were nonspecific but compatible with PG in the appropriate clinical context. The patient was managed primarily with systemic biologic therapy, conservative wound care, and strict avoidance of surgical trauma. Limited surgical excision was performed only after prolonged disease control and resulted in durable healing. Conclusion: This case highlights the diagnostic pitfalls of relying on histopathology alone in PG, emphasizes the rarity and non-ulcerative nature of palisaded neutrophilic and granulomatous dermatitis, and demonstrates that even extensive PG can heal without skin grafting when managed with appropriate systemic therapy and surgical restraint. Keywords: pyoderma gangrenosum, palisaded neutrophilic and granulomatous dermatitis, pathergy, inflammatory wounds
Yuen et al. (Fri,) studied this question.