A 22-year-old woman visited our clinic after developing a skin eruption over several days. On physical examination, there were well-demarcated yellowish vesiculobullous lesions with erythematous patches on both feet (Figure 1). The lesions were confined to the acral area of the distal extremities. Her medical record revealed Crohn disease diagnosed 10 years earlier. She was admitted to our internal medicine department because of bowel disease flare-up with abdominal pain, diarrhea, and fever. Her condition was controlled with total parenteral nutrition and medication with mesalamine, azathioprine, ciprofloxacin, and piperacillin-tazobactum, commencing on admission. Clinically, our patient was diagnosed as having contact dermatitis and was treated with topical and systematic corticosteroids. However, she continued to experience flare-ups in the 2 weeks after initial evaluation. A 4-mm punch biopsy specimen was obtained from a bullous lesion of the dorsum of the foot (Figure 2 and Figure 3).