Lymphocytic bronchitis unrelated to acute graft-versus-host disease in canine marrow graft recipients

We reviewed coded autopsy material from 71 dogs, 46 receiving allogeneic and 25 receiving autologous bone marrow transplants, to evaluate the hypothesis that lymphocytic bronchitis is associated with severe acute graft-versus-host disease (GVHD). We found no significant correlation between the presence of lymphocytic bronchitis and severe acute GVHD (P greater than 0.16). Using a binary regression model that corrected for possible confounding relationships, we failed to show a correlation between lymphocytic bronchitis and acute GVHD of each of the 3 classically affected organ systems. Also, no correlation was found between lymphocytic bronchitis and acute bacterial pneumonia (P greater than 0.32). Finally, lymphocytic bronchitis was present in autografted dogs with a prevalence at autopsy not significantly different from that of allografted dogs (P greater than 0.32). We conclude that lymphocytic bronchitis in this canine model represents nonspecific inflammation rather than acute pulmonary GVHD.