GASTRIC GRAFT-VERSUS-HOST DISEASE - A BLINDED HISTOLOGIC-STUDY

Acute graft-versus-host disease (GvHD) of the upper gastrointestinal ( GI) tract is common after allogeneic bone marrow transplantation (BMT) . However, diagnosis cannot be made on clinical presentation and endos copic findings alone, because these an nonspecific, and histologic con firmation is often desirable. The diagnosis of gastric GvHD is often b ased on subtle findings with considerable potential for variability in interpretation. Evaluation of the reproducibility of diagnosis and re cognition of histologic features of gastric GvHD was based on blinded review of 56 gastric biopsies (24 from patients with allogeneic BMT or unrelated umbilical cord blood transplantation and 32 control biopsie s from patients who did not undergo BMT, of whom eight had active GI c ytomegalovirus [CMV] infection). Histologic criteria for GVHD were apo ptosis and gland destruction, sparse inflammatory infiltrate, and gran ular eosinophilic debris in dilated glands. Seventeen patients (22 bio psies) were judged to have clinical GVHD on the basis of skin or liver involvement and GI symptoms without other known cause. Eighteen of th ese 22 gastric biopsies were classified as GvHD by at least two of the three pathologists on initial review. Blinded histologic diagnosis of GvHD had a positive predictive value of 69%, a sensitivity of 82%, an d specificity of 76%. False-positive results occurred in CMV gastritis , human immunodeficiency virus (HIV) infection, primary immunodeficien cy, and after renal transplantation. Of individual features, granular debris in glands was a specific (94% specificity), but insensitive (41 % sensitivity) marker for GVHD. Distinction between GvHD and CMV infec tion can be difficult, and GvHD can be confused with changes seen in H IV infection and other immunodeficiency states.