Severe de novo Ulcerative Colitis following Ixekizumab Therapy.

Ixekizumab is a selective monoclonal antibody targeting interleukin-17A, approved for the treatment of chronic plaque psoriasis. It has rarely been associated with inflammatory bowel disease (IBD) in randomized trials only. We report a unique case of severe new-onset ulcerative colitis in a young male complicated by cytomegalovirus infection who was on ixekizumab therapy for plaque psoriasis. We recommend that clinicians should exercise caution before prescribing ixekizumab as it seems to induce and exacerbate IBD.