Tubuloreticular inclusions in colonic mucosa as diagnostic markers of AIDS.

Tubuloreticular inclusions (TRI) are known to be associated with viral infections and are considered highly specific of the acquired immune deficiency syndrome (AIDS) in the appropriate clinical setting. We describe a homosexual man without any evidence of AIDS who presented with diarrhea. A search for the usual pathogens was unsuccessful, but electronmicroscopic examination of colonic mucosa revealed numerous tubuloreticular inclusions. The diarrhea subsided and 2 months later the patient developed Pneumocystis carinni pneumonia. This observation suggests that the detection of TRI in the colonic mucosa can precede the clinical manifestations of AIDS, and these structures can be useful markers for the future development of AIDS.