We investigated the radiologic features of pulmonary tuberculosis in HIV+ patients. METHODS 24 cases of pulmonary tuberculosis in HIV+ patients were studied (17 men and 7 women, average age: 38 years). The study includes 19 drug addicts, 3 homosexuals, 1 polytransfused subject and 1 patient not belonging to the categories considered at risk). Three subgroups were identified by the CD4/mm3 cell count (< 200, 200-500, > 500). RESULTS In our 24 patients, we identified 37 radiologic manifestations (in 13 cases associated in the same patient), with 6 cases of bilateral pulmonary and 9 atypical localizations. In detail: 10 consolidations, 7 productive (miliary) cavitations, 8 mediastinal lymphadenitis, 3 extrapulmonary forms and 4 cases with no chest X-ray alterations. There is a major frequency of consolidations and cavitations in the patients with CD4 > 200 and a major frequency of productive forms, lymphadenitis and extrapulmonary localizations in the subjects with CD4 < 200. We observed no cases of tuberculosis in patients with CD4 > 500. The medical therapy is usually more effective in the more immunocompetent subjects and, anyway, in the exudative forms, improving in 35% of cases, than in the productive and disseminated forms improving in 6% of cases only. CONCLUSIONS Only the severely immunodeficient HIV+ patients (CD4 < 500) are affected with tuberculosis. There exists a significant rate of parenchymal consolidations and tisiogenic forms in subjects with CD4 > 200 and a high rate of miliary forms, lymphadenitis and extrapulmonary localizations in patients with low cell count (< 200). The medical therapy is more effective in the more immunocompetent subjects and, anyway, in the exudative forms, than in the productive and disseminated forms. Finally, atypical localization of pulmonary tuberculosis are frequent in HIV patients.