“…8 Although IBD is the most common underlying cause of pyoderma gangrenosum in children, pyoderma gangrenosum in children can be associated with several other systemic disorders including immunodeficiencies (primary and HIV related), leukemia, hepatitis, and arthritis. 9,10 The occurrence of pyoderma gangrenosum preceding gastrointestinal symptoms in IBD has only been described in a few patients. 6,8,11 Perianal lesions including skin tags, fistulas, fissures, and abscesses are characteristic of Crohn's disease and occur during the course of IBD in 60% to 82% of patients; however, 25% to 30% of patients show perianal lesions before gastrointestinal complaints.…”