Adenovirus enterocolitis in human small bowel transplants

This report describes two cases of pediatric small bowel transplant patients who developed diffuse adenovirus enterocolitis of their allografts. Based upon the presenting symptoms for this complication, in both patients a differential diagnosis of allograft rejection versus viral infection was clinically entertained. The clinical condition in both instances rapidly deteriorated and both patients died shortly after the development of the symptoms of fulminant septicemia. Autopsies were performed and histologic examination revealed extensive denudation of the gastrointestinal mucosa with edema and a marked acute and chronic inflammatory infiltrate involving the entire wall of the grafts. Numerous viral intranuclear and intracytoplasmic inclusions were evident and an immunohistochemical stain specific for adenovirus was strongly positive in the infected cells. In addition, while in the first case the adenovirus appeared confined to the GI tract, the second patient displayed numerous viral inclusions in the lung as well as within multiple liver abscesses. At this point, the incidence of adenovirus as a cause of gastroenteritis in small bowel transplant patients remains to be determined. We believe that the importance of recognizing this particular type of viral infection in this group of patients lies primarily in differentiating it from other viral organisms (e.g., CMV) that require a specific antiviral therapy. Moreover, an identification of this entity could help avoid a misdiagnosis of rejection which could lead to an unnecessary increase in immunosuppressive therapy and a possible exacerbation of the underlying condition.