70 A 67Ga radionuclide

scan may show uptake in the right lower quadrant, although there may also be activity in the gastrointestinal tract, the liver, and the spleen. However, both tumor and inflammatory cells can bind gallium.71,72 The use of indium-labelled white cells will avoid this problem and will not be affected by neutropenia. Arteriography Protein Tyrosine Kinase inhibitor may show increased cecal vascularity with mucosal staining and dilatation of branches of the superior mesenteric artery. Also, there may be arteriovenous shunting as suggested by dilated, early-filling veins.73 Embolization of bleeding sites can be done although there is always a risk of transmural necrosis and perforation.35,73 Colonoscopy is not usually performed due to the severe leukopenia, thrombocytopenia, and fragile bowel wall but may reveal nodularity, ulceration, and hemorrhage.50 Macroscopically, the affected bowel is edematous, hemorrhagic, and thickened, with diffuse ischemic colitis in 69% of cases, a finding associated with increased mortality.36 The management of NE is controversial as it is based on only small case studies.36 Initially, patients should receive bowel rest, fluids, antibiotics, and, if needed, recombinant granulocyte colony stimulating factor. Non-operative treatment, found to be effective in many cases, is associated

with a 67% recurrence rate in one study from 1989.54 Surgery is indicated for persistent GI bleeding, perforation, uncontrolled sepsis, and an intra-abdominal process normally requiring surgery. Localized peritoneal CH5424802 in vitro signs do not constitute an adequate reason for intervention.35 For necrosis or perforation, a right hemicolectomy is advised.39 A cecostomy and drainage may be adequate in some cases.74 In cases where surgery is done on an emergency basis with an unprepared bowel or with perforation or gross peritonitis, a two-stage procedure rather than a primary anastomosis is advisable.75 It is controversial as to whether to resect a bowel that is thickened and edematous without perforation or necrosis.53 Complications developed

in 4.6% of patients with leukemia, most commonly abscess formation, such as hepatic abscess probably from seeding from the portal circulation;35 intussusception;29 postinflammatory find more colonic stricture;76 and obstruction.28 Acute abdominal conditions can be seen in both acute and chronic leukemias (5.3% and 2.6%, respectively).31 In acute leukemia, these episodes usually occur during periods of chemotherapy and are related to the primary disease, such as neutropenic colitis or splenic rupture. Acute cholecystitis may be managed with antibiotics delaying surgery until recovery of hematopoiesis.48 Rarely, myeloid leukemia cells infiltrate the gallbladder resulting in cholecystitis.27 Fatal acute abdominal catastrophes may occur with ischemic bowel.77 In chronic leukemia, abdominal conditions tend to develop randomly during the course of disease and are similar to those seen in an elderly population.