Psoriatic Skin Lesions Induced by Certolizumab Pegol

In 2010, a 26-year-old woman with Crohn's disease developed pustular psoriatic skin lesions after treatment with certolizumab pegol, an anti-TNF antibody. The lesions, confirmed by biopsy as psoriatic, affected her trunk, extremities, scalp, and palms/soles. Upon ceasing certolizumab and starting a regimen of oral prednisone, methotrexate (later switched to 6-mercaptopurine due to side effects), narrowband UV-B phototherapy, and topical treatments, her skin condition significantly improved. This case underscored that TNF inhibitors can induce or worsen psoriasis, necessitating the discontinuation of the drug and potentially requiring alternative psoriasis treatments. The Cimzia product insert was updated to include this side effect.