Diagnosis of disseminated mycobacterial infection: testing a simple and inexpensive method for use in developing countries

Bull World Health Organ. 1997;75(4):361-6.

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.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • AIDS-Related Opportunistic Infections / diagnosis*
  • AIDS-Related Opportunistic Infections / microbiology
  • Bacteremia / diagnosis*
  • Bacteremia / microbiology
  • Bacteriological Techniques
  • Blood / microbiology
  • Developing Countries
  • Humans
  • Mycobacterium Infections / diagnosis*
  • Mycobacterium Infections / microbiology
  • Mycobacterium avium Complex / isolation & purification
  • Mycobacterium avium-intracellulare Infection / diagnosis
  • Mycobacterium avium-intracellulare Infection / microbiology
  • Mycobacterium tuberculosis / isolation & purification
  • Tuberculosis / diagnosis
  • Tuberculosis / microbiology