Acute Graft versus Host Disease (GVHD) of Gastrointestinal Tract

Differential Diagnosis

Acute GVHD of GI Tract	Chemoradiation Toxicity
May occur up to 100 days post-transplant	May last 3-4 weeks

Impossible to distinguish histologically, especially for low grade GVHD

Acute GI GVHD vs. Opportunistic Infection

Consider infection in the setting of acute or chronic inflammation, neutrophilic crypt abscesses or ulceration
Use immunohistology to identify CMV or Herpes
Enteritis may also be nonspecific
Infection may coexist with GVHD