Skin manifestations of inflammatory bowel disease: clinical and therapeutic issues

This review focuses on the extraintestinal mucocutaneous manifestations of Crohn's disease (CD) and ulcerative colitis (UC). Current literature indicates the prevalence of specific lesions related to the activity of either CD or UC. These lesions have been classified into four categories: reactive skin manifestations, specific granulomatous lesions, nutritional deficiency states and miscellaneous. The reactive skin manifestations, which include aphthous ulcers, erythema nodosum and neutrophilic dermatosis, are considered to parallel frequently the activity, but not the severity of inflammatory bowel disease (IBD). Therapeutic approaches for the treatment of these manifestations include anti-inflammatory drugs and antibiotics. Specific granulomatous lesions, only seen in CD can be contiguous to the gastrointestinal tract or elsewhere including orofacial and genital regions. They occur independently from IBD activity. Treatment of this type of lesion is particularly difficult; steroids, antibiotics, immunosuppressive drugs and local surgery have been proposed; however they may be ineffective. Nutritional deficiency states induce secondary skin complications resulting from the malabsorption of essential dietary factors as a consequence of CD. The skin complications present as pigmentary disorders, pellagra and inflammation of the mouth and tongue (cheilitis and glossitis). Finally, the miscellaneous category relates to auto-immune diseases evolving independently from IBD and to common skin conditions found more frequently among patients with IBD, such as psoriasis.