Clinical, epidemiological, and therapeutic hallmarks of pyoderma gangrenosum: a case series of 35 patients.

Background: Over the past few decades, advances in medical research and diagnostic tools have shed light on some aspects of pyoderma gangrenosum (PG). Nevertheless, the multifactorial etiology, pathogenesis, and optimal management strategies for PG need to be further investigated. To address these knowledge gaps and contribute to a better understanding of this complex dermatological disorder, we collected epidemiological, clinical, and therapeutic aspects of a case series of PG patients occurring in our department over the past 10 years.

Methods: We performed a single-centered, retrospective, observational study analyzing all cases with a diagnosis of PG observed at the Dermatology clinic of the Fondazione Policlinico A. Gemelli IRCCS Catholic University from January 1, 2013, to January 1, 2023. For each case, we retrieved demographic data, the presence of other skin and systemic conditions, and the histopathological and clinical characteristics of PG, such as clinical variant, number of lesions, disease localization, previous therapy, response to treatment, and occurrence of relapse.

Results: We included 35 patients, 22 females and 13 males with a mean age of 40.0 years. Twenty patients (57.1%) had multiple localizations of disease, and the most commonly involved site was the lower limbs (85.7%). The lesions were mainly associated with inflammatory bowel diseases (51.4%) and hidradenitis suppurativa (37.1%). Clinical resolution with complete re-epithelialization was achieved in 25 patients (71.4%) with an average time of 20.8 months. On average, patients who underwent therapy with biological drugs had better outcomes.

Conclusions: PG is a severe, rare, and pleomorphic disease associated with a broad spectrum of conditions. Corticosteroids remain the primary first-line approach for severe forms, but using biological immunosuppressants is promising.