Possible Outbreak of Streptomycin-Resistant Mycobacterium tuberculosis Beijing in Benin

Using geographic information system and molecular tools, we characterized a possible outbreak of tuberculosis caused by Mycobacterium tuberculosis Beijing strain in 17 patients in Cotonou, Benin, during July 2005–October 2006. Most patients lived or worked in the same area and frequented the same local drinking bar. The isolates were streptomycin resistant

First Insight into a Nationwide Genotypic Diversity of Mycobacterium tuberculosis among Previously Treated Pulmonary Tuberculosis Cases in Benin, West Africa

Background. Molecular studies on tuberculosis (TB) are rare in low-resource countries like Benin, where data on molecular study on previously treated TB cases is unavailable. Materials and Methods. From January to December 2014, all smear- and culture-positive previously treated pulmonary TB patients from all TB clinics were systematically recruited. Drug susceptibility testing and spoligotyping were performed on all isolates. Results. Of the 100 patients recruited, 71 (71.0%) were relapse cases and 24 (24.0%) were failure cases, while 5 (5.0%) were default cases. Resistance rate to any first-line drug was 40.0%, while 12.0% of strains were multidrug-resistant (MDR) and no strain was extensively drug-resistant (XDR). A total of 40 distinct spoligotypes were found to be corresponding to a genotypic diversity of 40.0%. ST61 was the most predominant spoligotype with prevalence of 33.0%. In all, 31 single spoligotypes and nine clusters were observed with 2 to 33 strains per cluster giving a clustering rate of 69.0%. Euro-American (Lineage 4) was the most prevalent lineage (74.0%) and Lineage 2 was associated with resistance to streptomycin. Conclusion. This first insight into genetic diversity of previously treated pulmonary TB patients in Benin showed a relatively high genetic diversity of Mycobacterium tuberculosis

Genotypic characterization directly applied to sputum improves the detection of <i>Mycobacterium africanum</i> West African 1, under-represented in positive cultures

<div><p>Background</p><p>This study aimed to compare the prevalence of <i>Mycobacterium tuberculosis</i> complex (MTBc) lineages between direct genotyping (on sputum) and indirect genotyping (on culture), to characterize potential culture bias against difficult growers.</p><p>Methodology/Principal findings</p><p>Smear-positive sputa from consecutive new tuberculosis patients diagnosed in Cotonou, (Benin) were included, before patients had started treatment. An aliquot of decontaminated sputum was used for direct spoligotyping, and another aliquot was cultured on Löwenstein Jensen (LJ) medium (90 days), for indirect spoligotyping. After DNA extraction, spoligotyping was done according to the standard method for all specimens, and patterns obtained from sputa were compared versus those from the derived culture isolates. From 199 patient’s sputa, 146 (73.4%) yielded a positive culture. In total, direct spoligotyping yielded a pattern in 98.5% (196/199) of the specimens, versus 73.4% (146/199) for indirect spoligotyping on cultures. There was good agreement between sputum- and isolate derived patterns: 94.4% (135/143) at spoligotype level and 96.5% (138/143) at (sub)lineage level. Two of the 8 pairs with discrepant pattern were suggestive of mixed infection in sputum. Ancestral lineages (Lineage 1, and <i>M</i>. <i>africanum</i> Lineages 5 and 6) were less likely to grow in culture (OR = 0.30, 95%CI (0.14 to 0.64), p = 0.0016); especially Lineage 5 (OR = 0.37 95%CI (0.17 to 0.79), p = 0.010). Among modern lineages, Lineage 4 was over-represented in positive-culture specimens (OR = 3.01, 95%CI (1.4 to 6.51), p = 0.005).</p><p>Conclusions/ Significance</p><p>Ancestral lineages, especially <i>M</i>. <i>africanum</i> West African 1 (Lineage 5), are less likely to grow in culture relative to modern lineages, especially <i>M</i>. <i>tuberculosis</i> Euro-American (Lineage 4). Direct spoligotyping on smear positive sputum is effective and efficient compared to indirect spoligotyping of cultures. It allows for a more accurate unbiased determination of the population structure of the <i>M</i>. <i>tuberculosis</i> complex.</p><p>Trial registration</p><p>ClinicalTrials.gov <a href="https://clinicaltrials.gov/ct2/show/NCT02744469" target="_blank">NCT02744469</a></p></div

Availability of spoligotype patterns depending on the spoligotyping method used.

<p>Availability of spoligotype patterns depending on the spoligotyping method used.</p

Patients, specimens flow diagram and laboratory analyses.

<p>Patients, specimens flow diagram and laboratory analyses.</p

Time to culture positivity (on LJ medium) across lineages.

<p>Time to culture positivity (on LJ medium) across lineages.</p

Discrepancies: Spoligotype profile, lineage and sub-lineage.

<p>Discrepancies: Spoligotype profile, lineage and sub-lineage.</p

Effect of prior culture on spoligotyping analysis for MTBc lineage detection.

<p>Effect of prior culture on spoligotyping analysis for MTBc lineage detection.</p