Early and late-onset acute GvHD following hematopoietic cell transplantation: CT features of gastrointestinal involvement with clinical and pathological correlation

Objective: With the introduction of non-myeloablative hematopoietic cell transplantation, acute graft-versus-host-disease (GvHD) is frequently observed beyond the traditional 100 days cut-off. The aim of this study was to describe and compare CT features of gastrointestinal early and late-onset GvHD and to correlate findings with clinical and pathology grading. Subjects and methods: Abdominal CT scans were obtained in 20 patients with early and 15 with late-onset GvHD. Examinations were assessed for intestinal and extraintestinal abnormalities and findings compared between the two subgroups of GvHD. Distinct CT abnormalities as well as a CF-score integrating multiple pathologies were correlated with gut, clinical or pathology grading. Results: Frequent intestinal abnormalities included wall thickening, abnormal enhancement, and excessive fluid-filling (94%, 89%, and 94%). 86% of patients showed concomitant small and large bowel involvement. A discontinuous distribution was observed in 54%. Bile tract abnormality was the most common extra-intestinal finding (74%). The distribution of pathologies was equal between subgroups of early or late-onset disease. Wall thickening and mucosal attenuation in non-enhanced scans were significantly related to clinical and pathology scores (P <= 0.018). Number of abnormal segments, small bowel dilatation, engorgement of the vasa recta, mesenteric fat stranding and ascites were linked to clinical grading (P <= 0.019). A CT-score integrating multiple abnormalities was correlated to gut, overall clinical and pathology grading (r = 0.64, 0.57, 0.50). Conclusion: CT morphology of acute GvHD is independent of its time of onset and, thus, facilitates differential diagnosis of late-onset acute GvHD. Correlation of CT morphology with clinical and pathological grading is important in terms of prognosis and may help guiding the therapeutic approach. (C) 2009 Elsevier Ireland Ltd. All rights reserved.