All allogeneic (allo) and autologous (auto) hematopoietic stem cell transplantation (HSCT) recipients at St. Jude Children's Research Hospital undergo pre-HSCT computed tomography (CT) of the sinuses, chest, and abdomen because they are at significant risk for opportunistic infections. We studied whether this extensive routine imaging is warranted to detect infection despite the risk of additional radiation exposure. We reviewed the medical records of all children receiving allo- and auto-HSCT at St. Jude in 2004 and 2005. Of the 184 eligible patients who received 187 transplants, 131 received allografts and 56 autografts. Solid tumors and lymphomas were removed from the final analysis of the chest and abdomen CT as this imaging is typically warranted as part of disease restaging; thus, 111 allogeneic participants were included in this analysis. Both auto- and allo-recipients were evaluated by sinus CT and included in this final analysis. Most allo- and auto-HSCT recipients (> or =80%) did not have sinus, pulmonary, cardiac, or gastrointestinal symptoms; >85% of the evaluable allo-recipients had no prior fungal infection. Eighty-eight allo- and 31 auto-HSCT recipients had abnormal sinus CT findings, all unrelated to the underlying disease. Sixty-two (55.9%) of the allo-recipients had normal chest CT and 85 (76.6%) had normal abdominal CT. Of the 18 allo-recipients who began new therapy based on these findings, only 2 (11.1%) were related to chest CT findings and the other 16 were related to sinus findings. Our findings suggest that pre-HSCT routine CT imaging of the abdomen may not be warranted in a subset of allogeneic recipients who are asymptomatic and without previous infectious findings. Thus, these patients may be spared unnecessary radiation exposure. Recipients undergoing auto-HSCT or allo-HSCT for lymphomas or solid tumors will routinely undergo chest and abdominal CT imaging as part of their disease evaluation. The decision to perform chest CT should be made judiciously based on a careful history and physical examination. Sinus imaging, which was frequently abnormal, may be justified in all patients to plan post-HSCT care.