Analysis of clinical characteristics and factors affecting treatment responses in patients with pyoderma gangrenosum: a multicenter study of 239 patients☆

Background Pyoderma Gangrenosum (PG) is a chronic disease characterized by recalcitrant skin ulcers. Objective We aimed to evaluate the demographic, clinical characteristics, treatments and factors affecting the treatment responses of patients with PG. Methods We performed a multicenter study of 12 tertiary care centers. We analyzed the data of the patients who were followed up with a diagnosis of PG between the years 2012‒2022 retrospectively. Results We included a total of 239 patients of whom 143 were female and 96 were male, with an average age of 54.2 ± 17.4 years. The most common treatment was systemic steroids (n = 181, 75.7%). Among these patients, 50.8% (n = 92) used systemic steroids as the sole systemic agent, while 49.2% (n = 89) used at least one adjuvant immunosuppressive agent. The independent factors determined in regression analysis to influence response to systemic steroids positively were disease onset age ≥ 30-years, negative pathergy, absence of leukocytosis, negative wound culture, presence of a single lesion, and absence of upper extremity involvement. Biological agents were used in 18.4% (n = 44) of the patients in the present study. We also analyzed pathergy positive PG and early onset (onset age < 30) PG separately due to their distinct clinical features which were revealed during statistical analysis. Study limitations Retrospective nature of the present study. Conclusions Analyses of the factors influencing treatment responses are addressed in this study. Also, we concluded that investigation for accompanying autoinflammatory diseases of pathergy positive PG and early onset PG is necessary and the patients in these two groups are more resistant to treatment, necessitating more complicated treatments.