Abstract: Four days after cesarean section, the patient developed an ulcer at the incision site, accompanied by subjective pain and fever. Physical examination revealed a red ulcer with exudation and necrosis at the lower abdominal cesarean section incision. Antibiotic treatment was ineffective. Bacterial and fungal cultures of the incision site were negative. Histopathological examination showed epidermal destruction and massive neutrophilic infiltration in the dermis and subcutaneous tissue. The diagnosis of pyoderma gangrenosum was made. Methylprednisolone 40 mg/day was administered intravenously, combined with topical halometasone cream. The ulcer gradually shrank; five days later, the treatment was switched to oral prednisone acetate 20 mg,once a day, with gradual tapering. The ulcer healed completely one month later.

Key words: cesarean section, surgical incision, pyoderma gangrenosum