Neutropenic enterocolitis is a frequent autopsy finding in adult patients with acute leukemias. The predisposing factors other than neutropenia are not clear. There are also contradictions about treatment. Therefore, this entity still presents a diagnostic and therapeutic dilemma for clinicians. This retrospective study was performed to determine the incidence of neutropenic enterocolitis in adult leukemic patients, to examine the possible risk factors, clinical characteristics and treatment outcome. The pathogenesis is also discussed considering clinical and laboratory findings of the patients. The incidence of neutropenic enterocolitis was 6.5% for acute myeloid leukemia and 4.6% for acute lymphoblastic leukemia. The mean absolute neutrophil count at diagnosis was 48/mm(3) (median: 0/mm(3)). The median duration of severe neutropenia (absolute neutrophil count less than or equal to 500/mm(3)) on follow-up before the diagnosis was 32 days. Thirteen out of 20 patients had received antineoplastic drugs within the last 12 days, but 2 had not. Fourteen patients had signs of peritoneal irritation and 3 of them underwent surgery. The others received supportive measures, i.e. bowel rest, intravenous fluids, combinations of wide spectrum antibiotics, transfusions, hemodynamic supports and nasogastric decompression, if necessary. All 3 patients who underwent surgery survived, whereas only 1 of the 11 who received other treatments did. Six patients without signs of peritonitis were treated with antibiotics and the mentioned supportive measures. Four survived, but the others died due to sepsis. In conclusion, considering some recent reports that stated good outcome with conservative measures in the presence or absence of peritonitis, there is still debate regarding the optimal choice of treatment. The importance of early diagnosis cannot be overemphasized. Signs of peritoneal irritation indicate a life threatening condition. Surgery can be performed successfully in such patients. Long duration of neutropenia may be an important risk for neutropenic enterocolitis. (C) 1997 Elsevier Science Ireland Ltd.