Mycobacterial infections in human immuno-deficiency virus seropositive patients: role of non-tuberculous mycobacteria.

BACKGROUND: There is high prevalence of tuberculosis in patients with HIV infection; hence the role of non-tuberculous mycobacteria (NTM) in HIV patients has always been undermined. NTM may be responsible for clinical disease in a substantial number of immuno-compromised HIV sero-positive individuals even in a country endemic for Mycobacterium tuberculosis (M. tuberculosis). The study was designed to look for the contribution of NTM to morbidity in HIV seropositive patients. MATERIAL AND METHODS: In a prospective study of ninety-four HIV seropositive individuals presenting with pulmonary or extra-pulmonary symptoms suggestive of mycobacterial infection, appropriate samples were collected and processed. Detailed clinical history was utilized to differentiate colonization or contamination by NTM from true lung disease. RESULTS: Fourteen samples grew mycobacterial species, 8(57.2%) being NTM. The distribution of NTM was--3 M. avium complex, 2 M. fortuitum, 2 M. vaccae, 1 M. phlei. 6 isolates were M. tuberculosis. CONCLUSION: NTM may be responsible for a significant proportion of mycobacterial infections in HIV seropositive individuals. Despite the high endemicity of tuberculosis in developing countries like India, the presence of NTM should be ruled out; especially in immuno-compromised HIV seropositive individuals before instituting anti-tubercular therapy empirically. In addition, non-response of NTM to ATT may be wrongly attributed to multi-drug resistant tuberculosis.

Water soluble palmitic acid in media for cultivation of leprosy derived psychrophilic mycobacteria from Mycobacterium leprae infected tissues

Cultivation trials for Mycobacterium leprae resulted in growth of Mycobacterium psychrophilum (L). Media were inoculated with host grown Mycobacterium leprae cells from armadillo tissues, Nu mice foot pads or human lepromata. Cultures were obtained in liquid and on semisolid multifactoria 1 media containing water soluble palmitic acid or its salts. Ammonium thioglycolate and Napalmitate served as carbon and energy sources. The water soluble palmitic acid remained in perfect solution following sterilization in the autoclave, thus easily accessible to the cells. The cyclodextrin-Fe complex served as a siderophore to grow the obtained leprosy derived psychrophilic cells. The leprosy derived cultures and subcultures grew opimally at+10 degrees Celssius but deteriorated rapidly at + 32 degrees Celsius, in the multifactorial media. No growth occurred in 7H9 media. Cultures were not identified for classification.