Prevalence of multidrug-resistant tuberculosis cases among HIV-positive and HIV-negative patients eligible for retreatment regimen in Togo using GeneXpert MTB/RIF.

Drug-resistant tuberculosis (TB) is emerging as an important health problem in Togo. From sputum of previously treated TB patients, multidrug-resistant (MDR) TB was diagnosed in 24% (10/42) patients via GeneXpert MTB/RIF compared to 25% (6/24) patients via conventional drug susceptibility testing (BACTEC MGIT 960 system). The agreement between these two methods to detect MDR-TB is excellent. However, GeneXpert MTB/RIF offers the advantage of rapidly detecting Mycobacterium tuberculosis complex in sputum samples in instances where the cultures are negative (33%, 14/42) or contaminated (9.5%, 4/42). GeneXpert MTB/RIF permitted us to estimate the prevalence of MDR-TB in previously treated TB patients and to improve TB diagnostics among HIV-positive and -negative patients in Togo, where culturing M. tuberculosis complex from sputum samples is challenging.

Mycobacterium mucogenicum group infections: a review.

It has become apparent that Mycobacterium mucogenicum isolates recovered from clinical samples are more diverse than was previously realized and include an increasing number of emerging pathogens, as depicted by multilocus sequence analysis. Most clinically significant cases of those organisms involved catheter-related infections. They are susceptible to most antimicrobial agents, but like other rapidly growing mycobacteria, they are resistant to first-line antituberculous agents. A review of the cases of M. mucogenicum complex infection in the literature is addressed here, as well as two additional cases of the closely related species Mycobacterium aubagnense.

Interactions between Mycobacterium xenopi, amoeba and human cells.

Outbreaks due to Mycobacterium xenopi have been linked with contaminated water. M. xenopi has been shown to interact with the biofilm formed in water distribution systems and to be hosted by free-living Acanthamoeba. The present study investigated the interaction between M. xenopi and A. polyphaga amoeba, and between M. xenopi and human fibroblast HEL cells. Examination using the light microscopy together with electronic and confocal microscopy demonstrated that M. xenopi was located within the amoeba and in HEL cells. The Light Cycler measurement of the M. xenopi:A. polyphaga DNA ratio and the M. xenopi:HEL cell DNA ratio demonstrated intra-amoebal and intracellular growth of M. xenopi with doubling-times of five-days and 10 days, respectively. Intra-amoebal M. xenopi survived protozoan encystment and germination. These data demonstrate that M. xenopi is a facultative intra-amoebal and intracellular pathogen. Testing intra-amoebal M. xenopi might be necessary to properly evaluate decontamination procedures for hospital water supply systems in order to achieve eradication.