Graft versus host disease
Coronal and axial contrast-enhanced
CT images demonstrate wall thickening of the colon and distal ileum with areas
of thin mucosal enhancement, best seen within the rectosigmoid junction. There
is also diffuse engorgement of the vasa recta. The colon is predominantly
fluid-filled and there is a small volume of free fluid within the pelvis.
Subtle enhancement of the gallbladder wall is also noted.
Graft versus host disease (GVHD) is
a complication of allogeneic bone-marrow transplantation, in which donor bone
marrow T lymphocytes react to foreign host antigens and cause selected damage
to epithelial cells lining recipient target organs. The skin, gastrointestinal
tract, and liver are the most commonly involved organs. In addition to a characteristic
rash, patients present with nonspecific abdominal symptoms, such as cramping,
diarrhea, fever, nausea, vomiting, and anorexia. Due to the nonspecific nature
of the presenting symptoms, CT is often obtained for further evaluation. As
this diagnosis occurs in a specific patient, knowledge of the past medical
history of bone marrow transplantation is vital.
CT imaging classically demonstrates fluid-filled, thickened loops of bowel, often
with intervening segments of normal bowel. The involved loops of bowel may also
demonstrate enhancement of the mucosa as well as the serosa in some patients.
The small bowel, large bowel, duodenum, and stomach may be involved. Within the
mesentery adjacent to the involved bowel loops, vasa recta engorgement, and
infiltration of the mesenteric fat may be seen. Complications of bowel
involvement include perforation and abscess formation.
Extra-intestinal manifestations include involvement of the liver with hepatomegaly, periportal
edema, and enhancement of the gallbladder wall. A small volume of ascites is
also commonly seen.
GVHD occurs in acute and chronic forms, distinguished as occurring before and after
100 days following bone marrow transplantation. The diagnosis may be confirmed
via biopsy, often percutaneous liver biopsy or endoscopic gastric biopsy.
GVHD is treated with increased immunosuppression
and the prognosis is directly related to the severity of disease. Therefore
knowledge of the diagnosis and timely differentiation between GVHD and an infectious
enterocolitis is essential for the radiologist.
- Kalantari BN, Mortele KJ, Cantisani V, et al: CT features with pathologic correlation of acute gastrointestinal graft-versus host disease after bone marrow transplantation in adults. AJR Am J Roentgenol. 2003;181:1621-1625.
- Klingebiel T, Schlegal PG. GVHD: Overview on pathophysiology, incidence, clinical and biological features. Bone Marrow Transplant. 1998;21 Suppl 2:S45-49.
- Day DL, Carpenter BL. Abdominal complication in pediatric bone marrow transplant recipients. Radiographics. 1993;13:1101-1112.