A 29-year-old patient with prior history of a total colectomy and end ileostomy for fulminant ulcerative colitis presents with peristomal skin irritation and difficulty with leakage around the stoma. Painful, ulcerated purple nodules with violaceous borders are seen around the stoma site, as shown in the image below. Biopsy of the lesion shows neutrophil infiltration and perivascular lymphocytic infiltration and no infection. What is the best next step in management for this patient?