106 research outputs found
Operational research within the national tuberculosis control programme in Benin.
OBJECTIVE: To document whether the placement of operational research (OR) fellows within disease control programmes in low and middle income countries leads to the implementation of operational research and improvements in policy and practice. RESULT: In 2012, an OR fellow was placed within the National TB Programme, Benin, to strengthen the implementation of operational research. From 2012 to 2015, eight OR projects were implemented, of which three contributed to changes in programme practice and five provided information which was not previously available from quarterly/annual reports. Two of these projects-one on the burden and treatment outcomes of childhood TB and one on tracing patients who had discontinued treatment-are discussed in more detail. OR should be strongly encouraged within national TB programme settings and an OR fellow facilitates this process
Tuberculosis treatment raises total cholesterol level and restores high density lipoprotein cholesterol (HDLC) in patients with pulmonary tuberculosis
The aim of this study was to determine whether tuberculosis (TB) treatment normalizes the lipid profile strongly affected by pulmonary TB. Serum levels of total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C) and triglycerides (TG) were determined in 83 patients with pulmonary TB before and after treatment, and compared to results obtained from 100 control subjects without TB. Before treatment, levels of TC (p<0.005), HDL-C (p<0.005) and LDL-C (p<0.005) were significantly lower in pulmonary TB patients than normal subjects. Unlike TC and LDL-C, HDL-C decrease was correlated (r = 0.96, p<0.05) with smear positivity extent (SPE). At the end of TB treatment, which lasted six months, TC (p<0.01) and HDL-C (p<0.005) levels were significantly increased than before treatment while LDL-C stayed relatively unchanged. The treatment significantly reduced the atherogenic indices TC/HDL-C (p<0.001), LDL-C/HDL-C (p<0.001) and log (TG/HDL-C) (p<0.001) levels. Our results show that tuberculosis treatment increases TC levels and normalizes HDL while reducing atherogenic indices to below levels of controls.Keywords: Pulmonary tuberculosis, lipid profile, treatment, atherogenic indexAfrican Journal of Biotechnology Vol. 12(41), pp. 6019-602
Characteristics and Treatment Outcomes of Retreatment Tuberculosis Patients in Benin.
Objective. To determine among retreatment tuberculosis patients in Benin baseline characteristics, culture, and drug sensitivity testing (DST) results and treatment outcomes. Materials and Methods. A retrospective national cohort study of all retreatment tuberculosis patients in Benin in 2013 using registers and treatment cards. Results. Of 3957 patients with tuberculosis, 241 (6%) were retreatment cases. Compared to new pulmonary bacteriologically confirmed tuberculosis (NPBCT) patients, there were significantly higher numbers of males (P = 0.04), patients from "Atlantique-Littoral" (P = 0.006), patients aged 45-64 years (P = 0.007), and HIV-positive patients (P = 0.04) among those retreated. Overall, 171 (71%) patients submitted sputum for DST, of whom (163) 95% were positive for Mycobacterium tuberculosis on Xpert MTB/RIF and/or culture and 17 (10%) were rifampicin resistant (9 with MDR-TB and 8 monoresistant to rifampicin). For those without MDR-TB (n = 224), treatment success was 93%. Worse outcomes occurred in those with unknown HIV status (RR: 0.27; 0.05-1.45; P < 0.01) while better outcomes occurred in those who relapsed (RR: 1.06, 95 CI: 1.02-1.10, P = 0.04). Conclusion. In 2013, a high proportion of retreatment patients received DST. Treatment success was good although more needs to be done to systematically increase the final follow-up smear examination. Reasons of high losses to follow-up from "Oueme-Plateau" should be investigated
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
Whole-genome sequencing-based antimicrobial resistance characterization and phylogenomic investigation of 19 multidrug-resistant and extended-spectrum beta-lactamase-positive Escherichia coli strains collected from hospital patients in Benin in 2019
The increasing worldwide prevalence of extended-spectrum beta-lactamase (ESBL) producing Escherichia coli constitutes a serious threat to global public health. Surgical site infections are associated with high morbidity and mortality rates in developing countries, fueled by the limited availability of effective antibiotics. We used whole-genome sequencing (WGS) to evaluate antimicrobial resistance and the phylogenomic relationships of 19 ESBL-positive E. coli isolates collected from surgical site infections in patients across public hospitals in Benin in 2019. Isolates were identified by MALDI-TOF mass spectrometry and phenotypically tested for susceptibility to 16 antibiotics. Core-genome multi-locus sequence typing and single-nucleotide polymorphism-based phylogenomic methods were used to investigate the relatedness between samples. The broader phylogenetic context was characterized through the inclusion of publicly available genome data. Among the 19 isolates, 13 different sequence types (STs) were observed, including ST131 (n = 2), ST38 (n = 2), ST410 (n = 2), ST405 (n = 2), ST617 (n = 2), and ST1193 (n = 2). The blaCTX-M-15
gene encoding ESBL resistance was found in 15 isolates (78.9%), as well as other genes
associated with ESBL, such as blaOXA-1 (n = 14) and blaTEM-1 (n = 9). Additionally, we frequently
observed genes encoding resistance against aminoglycosides [aac-(6')-Ib-cr, n = 14],
quinolones (qnrS1, n = 4), tetracyclines [tet(B), n = 14], sulfonamides (sul2, n = 14), and
trimethoprim (dfrA17, n = 13). Nonsynonymous chromosomal mutations in the housekeeping
genes parC and gyrA associated with resistance to fluoroquinolones were also detected
in multiple isolates. Although the phylogenomic investigation did not reveal evidence of
hospital-acquired transmissions, we observed two very similar strains collected from
patients in different hospitals. By characterizing a set of multidrug-resistant isolates
collected from a largely unexplored environment, this study highlights the added value for
WGS as an effective early warning system for emerging pathogens and
antimicrobial resistance.The ARES (Académie de la Recherche pour l’Enseignement Supérieur), Belgium.http://www.frontiersin.org/Microbiologyam2022Genetic
Diagnostic accuracy of Xpert® MTB/RIF Ultra for childhood tuberculosis in West Africa - a multicentre pragmatic study
OBJECTIVE: To evaluate the performance of Xpert MTB/RIF Ultra ('Ultra') for diagnosis of childhood tuberculosis (TB) within public health systems. METHODS: In this cross-sectional study, children aged <15 years with presumptive pulmonary TB were consecutively recruited and evaluated for TB at tertiary-level hospitals in Benin, Mali and Ghana. Bivariate random-effects models were used to determine the pooled sensitivity and specificity of Ultra against culture. We also estimated its diagnostic yield against a composite microbiological reference standard (cMRS) of positive culture or Ultra. RESULTS: Overall, 193 children were included in the analyses with a median (IQR) age of 4.0 (1.1 - 9.2) years, 88 (45.6%) were female, and 36 (18.7%) were HIV-positive. Thirty-one (16.1%) children had confirmed TB, 39 (20.2%) had unconfirmed TB, and 123 (63.7%) had unlikely TB. The pooled sensitivity and specificity of Ultra verified by culture were 55.0% (95% CI: 28.0 - 79.0%) and 95.0% (95% CI: 88.0 - 98.0%), respectively. Against the cMRS, the diagnostic yield of Ultra and culture were 67.7% (95% CI: 48.6 - 83.3%) and 70.9% (95% CI: 51.9 - 85.8%), respectively. CONCLUSION: Ultra has suboptimal sensitivity in children with TB that were investigated under routine conditions in tertiary-level hospitals in three West African countries
Low sensitivity of the MPT64 identification test to detect lineage 5 of the Mycobacterium tuberculosis complex
Differentiation of the Mycobacterium tuberculosis complex (MTBc) from non-tuberculous mycobacteria (NTM) is important for tuberculosis diagnosis and is a prerequisite for reliable phenotypic drug-resistance testing. We evaluated the performance of the rapid MPT64 antigen identification test for the detection of Mycobacterium africanum lineage 5 (MAF L5).; Smear-positive tuberculosis patients' sputa were included prospectively. Culture was performed on Löwenstein-Jensen medium and, when positive, the MPT64 test and the classical para-nitro benzoic acid susceptibility and heat-labile catalase (PNB/catalase) identification tests were performed. The MPT64 test was repeated 14 days after an initially negative first testing. Direct spoligotyping was performed for MTBc lineage determination.; In total, 333 isolates were tested for all of the methods. Three hundred and twenty-two (96.7 %) were pure MTBc, by agreement between spoligotyping and PNB/catalase, and 11 were NTM or a mixture of MTBc/NTM. The MPT64 test conducted on day zero of culture-positivity correctly identified most of the pure MTBc isolates (93.2 %, 300/322), but it failed to detect 24 % of the L5 isolates (18/75) versus 2 % (4/202) of the L4 ones [OR=15.6 (5.3-45.8), P<0.0001], with improved sensitivity for L5 detection on repeat testing after 14 days. The L5-wide non-synonymous single-nucleotide polymorphism in the mpt64 gene may explain the poor performance of the MPT64 test for L5.; The MPT64 test has a lower sensitivity for detecting L5 isolates of the MTBc, and can be considered as a first-screening test that should be confirmed by another identification method when it produces negative results in countries with L5. Given the microbiological bias in both the isolation and identification of MAF lineages, diagnostics with high sensitivity for direct testing on clinical material are preferable
Phylogenomics of Mycobacterium africanum reveals a new lineage and a complex evolutionary history.
Human tuberculosis (TB) is caused by members of the Mycobacterium tuberculosis complex (MTBC). The MTBC comprises several human-adapted lineages known as M. tuberculosis sensu stricto, as well as two lineages (L5 and L6) traditionally referred to as Mycobacterium africanum. Strains of L5 and L6 are largely limited to West Africa for reasons unknown, and little is known of their genomic diversity, phylogeography and evolution. Here, we analysed the genomes of 350 L5 and 320 L6 strains, isolated from patients from 21 African countries, plus 5 related genomes that had not been classified into any of the known MTBC lineages. Our population genomic and phylogeographical analyses showed that the unclassified genomes belonged to a new group that we propose to name MTBC lineage 9 (L9). While the most likely ancestral distribution of L9 was predicted to be East Africa, the most likely ancestral distribution for both L5 and L6 was the Eastern part of West Africa. Moreover, we found important differences between L5 and L6 strains with respect to their phylogeographical substructure and genetic diversity. Finally, we could not confirm the previous association of drug-resistance markers with lineage and sublineages. Instead, our results indicate that the association of drug resistance with lineage is most likely driven by sample bias or geography. In conclusion, our study sheds new light onto the genomic diversity and evolutionary history of M. africanum, and highlights the need to consider the particularities of each MTBC lineage for understanding the ecology and epidemiology of TB in Africa and globally
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