Pyoderma gangrenosum: a 22-year follow-up of patients in a tertiary reference hospital in Brazil.

Background: Pyoderma gangrenosum (PG) is a rare dermatosis often associated with systemic diseases. There are autoinflammatory mechanisms with neutrophilic infiltrate and necrosis. Due to the high morbidity, variable response to therapy and lack of treatment standardization, PG constitutes a highly burdensome condition.

Objectives: To evaluate the epidemiological, clinical and laboratory features and response to therapy of patients with PG followed at HCFMUSP.

Methods: This retrospective and descriptive study included patients with confirmed PG under follow-up at HCFMUSP from January 2000 to August 2021. Data were retrieved from medical records.

Results: Fifty patients were included. The mean time from the onset of symptoms to diagnosis was 26.5 months. Lesions predominated on the lower extremity in 72% (n = 36/50), and the ulcerative type was the most common (n = 43/50; 86%). Local pain was mentioned in 39/50 (78%) and 12/50 (24%) presented pathergy. The most frequently associated diseases were inflammatory bowel disease (n = 10/20; 20%) and hidradenitis suppurativa (n = 10/20; 20%). High-dose systemic corticosteroid was mostly the first therapy (88%), either alone (n = 7/50; 14%) or in association with classic immunosuppressants or immunobiologicals (n = 37; 74%). Most patients (n = 32/50; 64%) had at least one hospitalization. Disease control was achieved in 44/50 (88%), with recurrences in 48% (n = 24/50) and total healing without medication in 24% (n = 12). Sixteen patients (32%) were treated with at least 1 immunobiological agent in addition to classic drugs.

Study Limitations: Retrospective, descriptive design and number of patients.

Conclusions: There was delay in diagnosis, association with systemic and cutaneous conditions, and the need for prolonged immunomodulatory or immunosuppressive therapy (classic agents and also biologic agents) to control PG.