Pyoderma gangrenosum (PG) is a debilitating skin condition characterized by deep, pus-filled, non-healing ulcers packed with neutrophils and is a common extraintestinal manifestation of inflammatory bowel disease (IBD). Strikingly, ∼40% of people with an initial presentation of PG go on to be also diagnosed with IBD, suggesting that both diseases have common factors driving their pathogenesis. The molecular and cellular mechanisms of PG and IBD co-development are currently unknown, hampering the development of effective treatment strategies for individuals affected by both diseases.