Mycobacterium tuberculosis bacteremia in patients with and without human immunodeficiency virus infection

To determine the incidence of Mycobacterium tuberculosis bacteremia in a general hospital and to describe the clinical characteristics, therapy, and outcome of patients with bacteremic tuberculosis.

Clinical charts of all patients in whom M tuberculosis was isolated from blood cultures during a 5-year period were reviewed. Mycobacterium tuberculosis was detected by means of a nonradiometric blood culture system.

Of 285 patients with culture-proved tuberculosis in whom blood cultures were obtained, 50 (14%) had M tuberculosis bacteremia. Of 42 patients analyzed, 34 (81%) were infected with human immunodeficiency virus (HIV) and eight (19%) were not infected with HIV. Blood was the only or the first positive specimen in 14 patients (33%). Most HIV-infected patients (79%) were intravenous drug users, and 40 (88%) had clinical and/or radiologic evidence of involvement of one or more organs. Lungs were affected in 71% of the patients. In-hospital mortality was 18% in HIV-infected patients with mycobacteremia. Among eight non-HIV-infected patients, four had an underlying disease, and none was immunosuppressed. Disseminated disease was diagnosed in three patients. Two patients died as a consequence of tuberculosis in this group.

Mycobacterium tuberculosis bacteremia is common in HIV-infected patients and is possible in nonimmunosuppressed subjects. Blood cultures are helpful in making the diagnosis of tuberculosis and can help establish a diagnosis of disseminated infection.