Sites of Tuberculous Involvement in Patients With AIDS: Autopsy Findings and Evaluation of Gallium Imaging

The purpose of this study was to review autopsy and gallium scan findings in two different acquired immune deficiency syndrome (AIDS) patient populations who had a confirmed diagnosis of tuberculosis (TB) to identify organs involved and accuracy of clinical diagnosis. The first group was comprised of 29 autopsies between January 1982 and December 1994, including only 18 patients who were diagnosed before death. Organs most commonly involved were the lymph nodes (59%), lungs(56%), spleen (53%), liver (45%), and kidneys (37%). Other opportunistic infections were present in 18 (59%) of autopsies, with more than one opportunistic infection present in 11 (37%) of the autopsies. Lungs were involved in 79% of all autopsies. The second population group included 94 patients with AIDS with a proven diagnosis of TB, only 24 of whom had gallium scans in the period between January 1992 and December 1994. Chest x-ray results were negative in 4 patients (17%); gallium scan results were positive in 16 patients (66%). The reasons for false-negative gallium scan results were due to anti-tuberculous treatment for periods varying from 2-21 months in 7 patients or the presence of extra pulmonary tuberculosis. The sites of TB involvement in the chest werelung parenchyma in 5 patients (19%, 4 in mid and lower lung, and 1 in upper lung fields). There was lymph node involvement in all 16 patients (24 locations) with mediastinal involvement in 23%, supraclavicular 23%, axillary 11%, retroperitoneal 11%, and inguinal region in 4%.We conclude that (1) tuberculosis in patients with AIDS behaves similar to primary tuberculosis; (2) the combination of chest x-ray and gallium imaging is sensitive for the diagnosis of pulmonary tuberculosis in patients with AIDS; (3) the involvement of mediastinal lymph nodes in gallium scans in the presence or absence of chest x-ray abnormalities should raise the possibility of TB involvement in patients with human immunodeficiency virus; (4) anti-TB treatment decreases the sensitivity of gallium scan.