Abdominal complications following hematopoietic stem cell transplantation

Abdominal complications affect more than 80% of patients who undergo hematopoietic stem cell transplantation (HSCT) for treatment of benign or malignant hematologic disease and some solid tumors. HSCT can be performed using cells from bone marrow, peripheral blood, or umbilical cord blood. These stem cells may be from the patient him- or herself (autologous transplant), from relatives or nonrelatives with very similar human leukocyte antigen (allogeneic transplant), or from an identical twin (syngeneic transplant). Posttransplantation complications are classified according to the amount of time elapsed between transplantation and onset. Complications that occur during the first 100 days are divided into preengraftment phase complications (≤30 days after transplantation) and early posttransplantation phase complications (31-100 days after transplantation) and include infectious and noninfectious conditions such as hepatic veno-occlusive disease (VOD), hemorrhagic cystitis, neutropenic colitis, benign pneumatosis, and acute graft-versus-host disease (GVHD). Hepatic VOD, neutropenic colitis, and acute hemorrhagic cystitis are associated with the pretransplantation conditioning regimen. After the first 100 days, chronic GVHD and lymphoproliferative disease are the main complications. Computed tomography and ultrasonography are the primary imaging techniques used in HSCT patients and can help make an early diagnosis, grade the severity of impact, and (if necessary) recommend further investigations to confirm the diagnosis.