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Gastrointestinal Complications Following Hematopoietic Stem Cell Transplantation in Children
Ji-Hye Lee, MD1 Gye-Yeon Lim, MD1 Soo Ah Im, MD1 Nak-Gyun Chung, MD2 Seung-Tae Hahn, MD1
Gastrointestinal system involvement is one of the principal complications seen in the recipients of hematopoietic stem cell transplantation (HSCT), and it is also a major cause of morbidity and death in thesepatients. The major gastrointestinal complications include typhlitis (neutropenic enterocolitis), pseudomembranous enterocolitis, viral enteritis, graft-versus-host disease, benign pneumatosis intestinalis, intestinal thrombotic microangiopathy, and post-transplantation lymphoproliferative disease. As these patients present with nonspecific abdominal symptoms, evaluation with using such imagingmodalities as ultrasonography and CT is essential in order to assess the extent of gastrointestinal involvement and to diagnose these complications. We present here a pictorial review of the imaging features and other factors involved in the diagnosis of these gastrointestinal complications in pediatric HSCT recipients.

Index terms : Hematopoietic stem cell transplantation Pediatric ComplicationsGastrointestinal tract DOI:10.3348/kjr.2008.9.5.449 Korean J Radiol 2008;9:449-457
Received November 12, 2007; accepted after revision March 6, 2008. Departments of 1Radiology and 2 Pediatrics, St. Mary’s Hospital, The Catholic University of Korea, Seoul 150713, Korea Address reprint requests to: Gye-Yeon Lim, MD, Department of Radiology, St. Mary’s Hospital, The Catholic University of Korea, 62, St.Mary’s Hospital, Youido-dong, Yongdungpo-gu, Seoul 150-713, Korea. Tel. (822) 3779-2168 Fax. (822) 783-5188 e-mail: shlgy@catholic.ac.kr Abbreviations: CMV = cytomegalovirus CsA = cyclosporine A GI = gastrointestinal GVHD = graft-versus-host disease HSCT = hematopoietic stem cell transplantation LDH = lactate dehydrogenase PMC = pseudomembranous colitis PTLD = post-transplantationlymphoproliferative disease TMA = thrombotic microangiopathy

ematopoietic stem cell transplantation (HSCT) is increasingly being used to treat many disorders ranging from hematologic malignancies to solid organ malignancies (1). However, all the recipients are at risk for a variety of post-transplant complications. Gastrointestinal tract involvement is a frequent complication that causes nonspecific symptoms(2, 3). The timing of complications that occur following transplantation is divided into three phases (4). The preengraftment phase lasts 15-30 days and it is characterized by marrow aplasia. The host defense barriers may be weakened during this pancytopenic period. The broadspectrum antimicrobial agents that are administered during this period are also a contributing factor for infection (3). Theearly post-engraftment period, i.e., from 30 to 100 days after transplantation, is characterized by the restoration of hematopoiesis. However, as lymphocyte recovery occurs more slowly, there is a continued deficiency of both cellular and humoral immunity during this period. The late, post-engraftment period begins only months or years after transplantation (4). The complications that ariseshortly after transplantation often result from the mucosal damage that’s secondary to the pre-transplantation chemotherapy and radiation therapy regimens, together with the immunosuppression of the pre-engraftment period and the infection that’s secondary to neutropenia. (4). The complications that occur later during the post-transplantation phase include chronic graft-versus-host disease (GVHD) andproliferative diseases such as post-transplantation lymphoproliferative disease (PTLD) or secondary malignant neoplasm (1, 4). Despite the fact that gastrointestinal complications remain a major cause of morbidity and mortality in pediatric HSCT recipients, there is only limited data regarding the imaging features of the gastrointestinal complications experienced by these patients (3). Careful...