Purpose or Case Report: Children undergoing hematopoietic stem cell transplantation (HSCT) are at high risk for infectious and non-infectious complications after transplant. While computed tomography (CT) is commonly used to identify asymptomatic infections or other abnormalities before transplant, there are limited data to support routine pre-transplant imaging with CT. We aimed to investigate the frequency of CT findings of infection, air trapping, or other unexpected abnormalities pre-HSCT.
Methods & Materials: Existing bone marrow transplant registry records were reviewed to identify all allogeneic HSCT recipients at our institution from May 2015 to May 2024. Reports and dates from CTs of the chest, abdomen, and pelvis obtained up to 90 days prior to a first-time transplant were recorded. Other relevant clinical data was recorded (e.g., donor source, match, absolute neutrophil count, and graft-versus-host disease status). Descriptive statistics were carried out to determine the relative frequency of infectious and non-infectious findings pre-HSCT.
Results: Of 636 total first-time allogenic transplant recipients, 551 underwent pre-HSCT CT imaging with a median time before HSCT of 30 days (range = 6-90), including 501 chest/abdomen/pelvis CTs, 68 chest-only CTs, and 2 abdomen/pelvis-only CTs. 120 CTs of the chest included dual-phase (inspiration and expiration) imaging. 28% (159/569) of chest CTs reported possible infection pre-HSCT. Baseline air trapping was reported in 18% (22/120) of dual-phase CTs. 3% (17/503) of abdomen/pelvis CTs suggested possible infection.
Conclusions: Chest CTs reported findings of possible infection in more than a quarter of patients prior to HSCT. Air trapping was present in nearly a fifth of dual-phase CTs at baseline, which may be relevant to accurately identifying post-transplant bronchiolitis obliterans and patients at risk for non-infectious pulmonary complications. Findings of possible infection in the abdomen and pelvis were rare. Our results suggest pre-HSCT CT for surveillance of asymptomatic infection could be limited to the chest, decreasing radiation exposure and eliminating the need for IV contrast.