title: Diagnosis of disseminated mycobacterial infection: testing a simple and inexpensive method for use in developing countries.
abstract: With the development of the acquired immunodeficiency syndrome (AIDS) epidemic, the isolation of mycobacteria from blood has become a common problem for clinical laboratories. In this study two methods were used for the recovery of mycobacteria from blood specimens obtained from AIDS patients: (1) direct inoculation of a biphasic medium, and (2) a non-commercial lysis-centrifugation method. A total of 3 consecutive blood samples were taken at 15-minute intervals from each of 50 AIDS patients with clinical suspicion of disseminated mycobacterial disease. Mycobacterium growth was noted in 70/138 blood specimens from 30 (60%) patients. These cultures yielded Mycobacterium tuberculosis in 19 (63%) and Mycobacterium avium complex organisms in 11 (37%) patients. Cultures using the lysis-centrifugation method were positive in 54% of the patients while cultures using biphasic medium were positive in 44% (P > 0.05). The positivity for M. avium complex was higher with lysis-centrifugation (91%) than with biphasic medium (45.4%) (P < 0.05). However, the positivities for M. tuberculosis with the lysis-centrifugation method (89.5%) and direct inoculation in biphasic medium (100%) were similar (P > 0.05). The use of a non-commercial lysis-centrifugation technique is inexpensive, reliable, and can be an alternative method for the diagnosis of mycobacteraemia in developing countries.
authors.affiliation: Microbiology Institute, Federal University of Rio de Janeiro, Brazil.
authors.forename: F C
authors.initials: FC
authors.lastname: Fandinho
authors.forename: B
authors.initials: B
authors.lastname: Grinsztejn
authors.forename: V G
authors.initials: VG
authors.lastname: Veloso
authors.forename: M C
authors.initials: MC
authors.lastname: Lourenço
authors.forename: E
authors.initials: E
authors.lastname: Werneck-Barroso
authors.forename: E
authors.initials: E
authors.lastname: João
authors.forename: S A
authors.initials: SA
authors.lastname: Nogueira
authors.forename: L de S
authors.initials: Lde S
authors.lastname: Fonseca
mesh_terms: D017088:AIDS-Related Opportunistic Infections / Q000175:diagnosis* / Q000382:microbiology; D016470:Bacteremia / Q000175:diagnosis* / Q000382:microbiology; D001431:Bacteriological Techniques; D001769:Blood / Q000382:microbiology; D003906:Developing Countries; D006801:Humans; D009164:Mycobacterium Infections / Q000175:diagnosis* / Q000382:microbiology; D015269:Mycobacterium avium Complex / Q000302:isolation & purification; D015270:Mycobacterium avium-intracellulare Infection / Q000175:diagnosis / Q000382:microbiology; D009169:Mycobacterium tuberculosis / Q000302:isolation & purification; D014376:Tuberculosis / Q000175:diagnosis / Q000382:microbiology