Gastrointestinal Biopsies for Evaluation of Acute Graft-Versus-Host Disease in Allogeneic Hematopoietic Stem Cell Transplant Patients.

Graft-versus-host disease (GVHD) is the major complication post hematopoeitic stem cell transplantation (HSCT) causing significant morbidity and mortality. Colonic biopsies were performed in 25 post HSCT patients presenting the diarrhea for diagnosis of acute graft versus host disease (A-GVHD). The present study was undertaken to evaluate and illustrate histomorphological features of A-GVHD in GI biopsies and to grade them. Histopathological features of gastrointestinal biopsies from 25 allogeneic HSCT patients having clinical suspicion of A-GVHD were evaluated and compared with colonic biopsies from negative controls. A-GVHD was observed in 17 cases, CMV colitis was present in 3 cases and one case had herpes simplex infection diagnosed in conjunction with serological findings. A-GVHD was graded as grade 1 and 2 in 10 cases and grade 3 and 4 in 7 cases. Apoptosis of crypt epithelial cells was the cardinal feature for diagnosis. Grade 1 and grade 2 A-GVHD cases showed crypt apoptosis in all cases as well as pericryptal apoptosis in lamina propria in many cases. Occasional crypt loss was seen in grade 2 GVHD. Inflammatory infiltrate was composed of lymphocytes and plasma cells. Neutrophils were inconspicuous. Grade 3 and grade 4 A-GVHD cases showed contiguous areas of multiple crypt loss and ulceration with inflammatory infiltrate predominantly composed of lymphocytes and plasma cells, but neutrophils were more prominent than in grade 1 and 2 A-GVHD. Apoptosis of crypt epithelial cells was present in all grade 3 &4 cases except one case. CMV cases were diagnosed by CMV inclusions and IHC stain. Several factors including drug-induced side effects and infections can cause difficulty in histologic interpretation of gastrointestinal biopsies for GVHD. Proper histomorphological interpretation of intestinal A-GVHD is critical for clinical management. A-GVHD is treated with immunosuppression which may worsen infective condition, if present.