Pustular Psoriasis: An Extra-Intestinal Manifestation of Inflammatory Bowel Disease or an Adverse Effect of Anti-TNFα Treatment?: A Case Report

Abstract

Pustular psoriasis, a rare variant of psoriasis, can be associated with inflammatory bowel diseases (IBD), such as ulcerative colitis and Crohn's disease. Both conditions share immunological mechanisms, systemic inflammation, and genetic factors. Anti-TNF-α therapy can cause adverse effects such as psoriasiform skin reactions. We report the case of a 46-year-old female patient, who presented with multiple aphthoid ulcers in the intestinal mucosa and acute-on-chronic inflammation, diagnosed with IBD-Unclassified. After one year of Adalimumab therapy, pruritic skin lesions emerged on the scalp and chest, progressing to desquamative plaques and pustules on the left leg. The skin biopsy revealed histopathological findings compatible with pustular psoriasis. The use of topical corticosteroids for 4 months led to remission of the skin lesions. With the combination treatment of Adalimumab and Azathioprine, there was stabilization of the intestinal inflammation, which was confirmed by colonoscopy and histological examinations. The patient remains in clinical remission, with no signs of IBD exacerbation, and did not develop any further skin lesions. This study reinforces the relevance of early diagnosis and a multidisciplinary approach in managing pustular psoriasis associated with inflammatory bowel disease, allowing for swift intervention and a reduction in clinical complications.