Treatment of Pyoderma Gangrenosum, Erythema Nodosum, and Aphthous Ulcerations

Pyoderma gangrenosum, erythema nodosum, and aphthous ulceration are extraintestinal manifestations of inflammatory bowel disease associated with active mucosal inflammation. Because the frequency of these problems is relatively low in the pediatric population, large therapeutic clinical trails have not been conducted. Therefore, therapeutic intervention is guided mostly by anecdotal experience. Pyoderma gangrenosum is a deep ulceration of the skin often precipitated by minor trauma such as intravenous sites. Children with ulcerative colitis are more likely to develop pyoderma gangrenosum than are children with Crohn's disease, but still only ˜4% of all patients with pyoderma gangrenosum are <18 years of age (1). The clinical appearance of lesions in the pediatric and adult populations is similar, and the involvement of the lower extremities is more frequent in both groups; however, pyoderma gangrenosum of the head and face is more common in children. Treatment is based on immunosuppressive therapy to control mucosal inflammation. A high-dose pulse of corticosteroids of 2-4 mg/kg/day (with a maximum of 120 mg/day) followed by a rapid taper over 1-2 weeks to the baseline dose of corticosteroid therapy or to an alternate-day dose usually controls the colonic and the dermatologic inflammation. Recurrence of the skin lesions may occur as immunosuppressive therapy is weaned and scarring may result, requiring skin grafting to complete healing. Ultimately, control of colonic inflammation with immunoregulatory therapy will prevent recurrence of the pyoderma gangrenosum in most children. Erythema nodosum appears to be more common in patients with Crohn's disease. Like pyoderma gangrenosum, erythema nodosum often improves with therapy directed at control of mucosal inflammation. The therapy is similar. However, some children will not experience severe gastrointestinal symptoms, yet have discomfort of the skin lesions. Therapy with medications such as thalidomide or tumor necrosis factor antibodies that regulate tumor necrosis factor synthesis may prove to be effective therapy, but have had limited use in the pediatric population. Aphthous ulceration may be painful and resistant to therapy. The cause of these oral lesions may be difficult to identify, but infectious etiologies such as herpes simplex or cytomegalovirus must be considered before initiating immunoregulatory-based therapy. Appropriate cultures and microscopic evaluation should be obtained. Predisposing factors such as trauma or nutritional deficiencies of folate, iron, vitamin B12, and zinc may contribute to the persistence of ulceration and should be corrected. Topical application of 0.1% dexamethasone is not as effective when prescribed as a rinse as when applied with a cotton swab held directly on the lesion for 5 min. The use of cyanoacrylate adhesive may provide symptomatic relief and increase healing (2).