DIAGNOSIS OF DISSEMINATED MYCOBACTERIAL INFECTION - TESTING A SIMPLE AND INEXPENSIVE METHOD FOR USE IN DEVELOPING-COUNTRIES

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 use d for the recovery of mycobacteria from blood specimens obtained from AIDS patients: (I) direct inoculation of a biphasic medium, and (2) a non-commercial lysis-centrifugation method A total of 3 consecutive bl ood samples were taken at 15-minute intervals from each of 50 AIDS pat ients with clinical suspicion of disseminated mycobacterial disease. M ycobacterium 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. Cult ures 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-ce ntrifugation (91%) than with biphasic medium (45.4%) (P < 0.05). Howev er, 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 noncommercial lysis-centrifugation te chnique is inexpensive, reliable, and can be an alternative method for the diagnosis of mycobacteraemia in developing countries.