Infliximab-Associated Psoriasiform Dermatitis: Case Report and Review of a Seemingly Paradoxical Inflammatory Response

BACKGROUND Tumor necrosis factor-α (TNF-α) inhibitors, such as infliximab, adalimumab, and certolizumab pegol are effective agents in the treatment of inflammatory bowel disease. Some individuals undergoing anti-TNF-α therapy for Crohn's disease or ulcerative colitis develop psoriasiform lesions. This is a paradoxical finding, as classical psoriasis is known to respond to these agents. PURPOSE The clinical features of anti-TNF-α-induced psoriatic dermatitis are described. METHOD A 60-year-old man with Crohn's disease treated with infliximab, who developed anti-TNF-α-induced psoriasiform dermatitis, is described. RESULTS The man developed erythematous skin lesions in the bilateral axillae two years after beginning infliximab treatment for Crohn's disease. Biopsy revealed psoriasiform dermatitis, consistent with a diagnosis of anti-TNF-α-induced psoriasiform dermatitis. He was treated with clobetasol 0.05% ointment twice daily for two weeks and had significant improvement. Subsequently, he used the corticosteroid ointment two days per week and calcipotriene 0.005% ointment twice daily for five days per week to achieve and maintain clear skin. CONCLUSIONS Anti-TNF-α-induced psoriasiform dermatitis is an infrequent complication of infliximab therapy. However, the condition may require discontinuation of the anti-TNF-α agent. Anti-TNF-α-induced psoriasiform dermatitis should be considered in the differential diagnosis when evaluating a new erythematous skin condition in an individual with a history of inflammatory bowel disease who is being treated with a TNF-α inhibitor.