Mayo Clin Proc, October 2002, Vol 77 Letters to the Editor 1133 Mayo Clin Proc. 2002;77:1133-1134 © 2002 Mayo Foundation for Medical Education and Research Letters to the Editor 1133 Enterocolitis as Initial Presentation of Acute Myelogenous Leukemia Exacerbated by Induction Chemotherapy With Idarubicin-Cytosine Arabinoside To the Editor: The article by Hogan et al 1 reporting the incidence of neutropenic colitis after induction with idarubicin and cytosine arabinoside is relevant to a recent interesting case at our institution. A 53-year-old woman presented to the emergency de- partment because of intermittent severe abdominal pain of 3 days’ duration. She described primarily right-sided abdominal pain with subjective fever and occasional loose stools. Physical examination was remarkable for fever and tenderness to palpation in the right upper and lower quadrants with accompanying peritoneal signs. A complete blood cell count revealed an elevated white blood cell count of 89.7 × 10 9 /L with absolute neutrophil count of 23.0 × 10 9 /L, hemoglobin value of 7.3 g/dL, and platelet count of 142 × 10 9 /L. Myelomonocytic blasts were present on the peripheral smear. Abdominal com- puted tomography revealed pericolonic stranding and mu- cosal thickening involving the cecum and proximal ascend- ing colon. This presentation was consistent with typhlitis in the presence of underlying leukemia, confirmed as acute myelogenous leukemia French-American-British (FAB) type M4 on subsequent bone marrow biopsy. Although enterocolitis is a rare presenting complication of hemato- logic malignancies, it has been reported. 2,3 The patient was admitted and treated with broad-spec- trum antibiotics, bowel rest, and hydration. Stool cultures were negative for enteric pathogens. After 3 days of antibi- otic treatment, the patient’s abdominal pain resolved com- pletely. She was given idarubicin, 12 mg/m 2 , and cytosine arabinoside, 100 mg/m 2 . On day 4 of induction, she devel- oped right lower quadrant pain, fever, diarrhea, and tenes- mus. The patient’s absolute neutrophil count at that time was 0.6 × 10 9 /L. Repeated computed tomography of the abdomen revealed bowel wall thickening up to 1 cm involving the entire colon, consistent with a diagnosis of neutropenic en- terocolitis. The patient was treated supportively with bowel rest, broad-spectrum antibiotics, hydration, and parenteral nutrition. After 15 days, the patient’s neutropenia and ab- dominal pain resolved. Stool and blood cultures were nega- tive during the period of neutropenia. This patient’s presentation is intriguing because the original typhlitis was likely related both to the leukemia and an infectious process. This theory is supported by the patient’s resolution of symptoms with supportive care and antibiotics. These factors leading to colitis were then likely unmasked and exacerbated by the resultant immunosup- pression and additive effects of the chemotherapy on a likely altered bowel mucosa. Hogan et al proposed that the etiology of observed enterocolitis is likely related to toxic effects secondary to idarubicin and cytosine arabinoside therapy or an undiagnosed infectious process. One could argue that in our case the cause was multifactorial with an infectious component (treated initially with antibiotics and supportive care) that later progressed because of additive toxic chemotherapeutic effects and immunosuppression. This theory supports what other authors 4 have proposed as etiologies in patients with neutropenic enterocolitis. Never- theless, it is clear from the article by Hogan et al and this case that induction chemotherapy with idarubicin and cy- tosine arabinoside is responsible for pronounced morbidity related to the development of enterocolitis in a substantial portion of treated patients. Capt Roger A. Wood, USAF Wilford Hall Medical Center San Antonio, Tex The views in this article do not reflect the views of the Depart- ment of Defense or the United States Air Force. 1. Hogan WJ, Letendre L, Litzow MR, et al. Neutropenic colitis after treatment of acute myelogenous leukemia with idarubicin and cy- tosine arabinoside. Mayo Clin Proc. 2002;77:760-762. 2. Quigley MM, Bethel K, Nowacki M, Millard F, Sharpe R. Neutro- penic enterocolitis: a rare presenting complication of acute leukemia. Am J Hematol. 2001;66:213-219. 3. Ahsan N, Sun CC, Di John D. Acute ileotyphlitis as presenting manifestation of acute myelogenous leukemia [published correction appears in Am J Clin Pathol. 1988;89:813]. Am J Clin Pathol. 1988;89:407-409. 4. Gomez L, Martino R, Rolston KV. Neutropenic enterocolitis: spec- trum of the disease and comparison of definite and possible cases. Clin Infect Dis. 1998;27:695-699. Use of Low-Molecular-Weight Heparin in Pregnant Women With Mechanical Valves To the Editor: In his review of preconception care, Dr Frey 1 notes that low-molecular-weight heparin is an option for pregnant women at thromboembolic risk, including those with mechanical heart valves, in accordance with the most recent bulletin from the American College of Obstet- rics and Gynecology. 2 Low-molecular-weight heparin is not approved for this indication. The package insert for enoxaparin (Lovenox) explicitly discourages this use; it describes a study of 7 pregnant women with mechanical For personal use. Mass reproduce only with permission from Mayo Clinic Proceedings.