TNF and Crohn disease: However, we also note that some tumor necrosis factor inhibitors may induce the onset of vitiligo, a phenomenon observed in patients with various other conditions, such as hidradenitis suppurativa, ankylosing spondylitis, Crohn’s disease, and psoriasis (Dunn et al., 2019; Anthony et al., 2020; Phan et al., 2020).