The main purpose of this report is to focus on the importance of an accurate etiologic diagnosis of gastrointestinal complications during chemotherapy for acute myeloid leukemia, taking into account that a syndrome characterized by bowel wall thickening associated with diarrhea and abdominal pain may have etiologies different from neutropenic enterocolitis (NE) and in such a case necessitate a different treatment approach. We describe a case of a 46-year-old woman affected by acute myeloid leukemia presenting the onset of a syndrome with clinical features of NE. Supportive therapy for NE was instituted, but during treatment the patient presented a life-threatening gastrointestinal bleeding and was submitted in emergency to hemicolectomy. Following surgery, the patient recovered completely and she is currently alive in complete remission after receiving allogeneic bone marrow transplantation. Histological examination of the surgical specimens showed that the acute abdominal syndrome was related to massive infiltration of the bowel by leukemia cells. A correct baseline evaluation and a prompt diagnosis of the complication may help in making the therapeutic decision, which in our case led necessarily to a surgical procedure, because the bleeding was due to post-chemotherapy necrosis of the leukemic infiltrating tissue. A close collaboration between the hematologist and the surgeon may provide guidelines for behavior in such cases, giving these patients the possibility of survival and the opportunity to carry on the treatment planned for the primary disease.