scholarly journals LUCIFERASE REPORTER MYCOBACTERIOPHAGES FOR EVALUATING NORBORNENE-BASED ANTITUBERCULOSIS DRUG SUSCEPTIBILITY TESTING ON MYCOBACTERIUM TUBERCULOSIS

Author(s):  
Kalaiselvi K ◽  
Mangayarkarasi V ◽  
Gomathi Ns ◽  
Balaji S ◽  
Shivshankar R Mane ◽  
...  

  Objective: In 2015, 9.6 million people around the world became sick with tuberculosis (TB) disease and 1.5 million TB-related deaths worldwide. Recent increasing incidence of multidrug-resistant (MDR; resistance to at least rifampicin (RIF) and isoniazid [INH]) and extensively drug-resistant (MDR resistance plus resistance to a fluoroquinolone and an aminoglycoside) makes TB a serious concern. Lot of research is needed to deal with this infectious disease for a better alternative in treatment or modification of these older TB drugs. The present study aimed at evaluating antimycobacterial activity of norbornene (NOR) derived INH copolymer with poly ethylene glycol (NOR- polyethylene glycol [PEG]-INH) a novel nanocarrier along with the anti-TB drug using luciferase reporter phages (LRPs).Methods: NOR derived INH accounts for 74% of INH, 24% of NOR, and 2% of PEG. H37Rv control strain, a sensitive, and a resistant strain of Mycobacterium TB (MTB) used in this study. The in vitro activity of the drug was evaluated using absolute concentration method. The resistant strain was evaluated using LRP assay to observe the minimum inhibitory concentration of the drug.Results: Reduction in light units was observed for the resistant strain exposed to plain INH and NOR-PEG-INH separately. 24% of reduction was observed in strains exposed to plain INH whereas 37% of reduction was observed in strains exposed to NOR-PEG-INH.Conclusion: NOR-based INH had better antimycobacterial activity compared to plain INH and RIF. Antimycobacterial activity of INH and RIF increases even with very low dosage with NOR conjugate.

Author(s):  
Dian Ayu Eka Pitaloka ◽  
Elin Yulinah Sukandar

Objective: The resurgence of tuberculosis (TB) caused by Mycobacterium TB (MTB) is associated with the rapid spread of multidrug-resistant,therefore, the development of new antimycobacterial agents is necessary. The aim of this study was to evaluate the antimycobacterial activity ofursolic acid (UA) when it using alone and combination with TB drugs.Methods: MTB H37Rv strain, streptomycin-rifampicin resistant strain, and isoniazid-ethambutol resistant strain were evaluated by susceptibility testusing a serial number of UA (25-150 µg/mL). Minimum inhibitory concentration (MIC) was read as minimum concentration of drugs that completelyinhibit visible growth of organism. Activities of drug combination of UA with TB drug were determined in Lowenstein-Jensen media by calculatingthe fractional inhibitory concentration index.Results: The results showed that MIC of UA was 50 µg/mL against three different strains of MTB. The combination of UA and TB drugs displayedsynergistic interaction, and no antagonism result from the combination was observed for strains of MTB.Conclusion: These results indicate that UA may serve as a promising lead compound for future antimycobacterial drug development.Keywords: Ursolic acid, Tuberculosis, Drug combination, Susceptibility test


2019 ◽  
Author(s):  
Mohammad Javad Nasiri ◽  
Sirus Amini ◽  
Zahra Nikpor ◽  
Samaneh Arefzadeh ◽  
Mohammad Mosavi ◽  
...  

AbstractIntroductionMycobacterium simiaeis an emerging pathogen in Iran and little is known about drug susceptibility patterns of this pathogen.Materials and methodsTwenty five clinical isolates ofM. simiaefrom 80 patients with confirmed NTM pulmonary disease were included in this study. For drug susceptibility testing (DST), proportional and broth microdilution methods were used according to the clinical and laboratory standards institute (CLSI) guideline.ResultsAll clinical isolates ofM. simiaewere resistant to isoniazid, rifampicin, ethambutol, streptomycin, amikacin, kanamycin, ciprofloxacin and clarithromycin. They also were highly resistant to ofloxacin (80%). Susceptibility to ofloxacin was only noted in the 5 isolates.ConclusionsClinical isolates ofM.simiaewere multidrug resistant, and had different drug susceptibility patterns than previously published studies. DST results can assist in selecting more appropriate treatment regimens. Newer drugs with proven clinical efficacy correlating with in vitro susceptibility should be substituted with first- and second line anti-TB drug testing.


Author(s):  
Thi Van Anh Nguyen ◽  
Richard M Anthony ◽  
Thi Thu Huyen Cao ◽  
Anne-Laure Bañuls ◽  
Van Anh Thi Nguyen ◽  
...  

Abstract Delamanid, a-first-in-class bicyclic nitroimidazole, was recently approved for multidrug-resistant tuberculosis treatment. Pitted against the hope for improving treatment outcomes is the threat of the rapid resistance emergence. This review provides information on the mechanisms of action, resistance emergence, and drug susceptibility testing (DST) for delamanid. Delamanid resistance has already been reported in both in vitro experiments and clinical settings. Although mutations conferring delamanid resistance have been identified in fbiA, fbiB, fbiC, ddn, and fgd1 genes of Mycobacterium tuberculosis, knowledge about the molecular resistance mechanisms is limited, and there remains no standardized DST method. The rapid acquisition of delamanid resistance emphasizes the need for optimal use of new drugs, the need for drug resistance surveillance, and a comprehensive understanding of drug resistance mechanisms. Further studies are necessary to investigate genetic and phenotypic changes that determine clinically relevant delamanid resistance to help develop a rapid delamanid DST.


Antibiotics ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 797
Author(s):  
Vichita Ok ◽  
Alexandra Aubry ◽  
Florence Morel ◽  
Isabelle Bonnet ◽  
Jérôme Robert ◽  
...  

The MDR/MTB ELITe MGB® kit (ELITech) carried on the ELITe InGenius® platform is a new real-time PCR assay allowing automated extraction and detection of DNA of the Mycobacterium tuberculosis complex (MTB) and mutations in the rpoB and katG genes and inhA promoter region (pro-inhA) associated to resistance to rifampicin and isoniazid, the two markers of multidrug-resistant TB (MDR). We assessed the performances of the test on a collection of strains (n = 54) and a set of clinical samples (n = 242) from routine practice, comparatively to TB diagnosis and genotypic drug susceptibility testing (gDST) as references. Regarding the 242 clinical samples, the sensitivity and specificity of MTB detection by ELITe were 90.9% and 97.5%, respectively. For the detection of resistance-conferring mutations on positive clinical samples, we observed perfect agreement with gDST for katG and pro-inhA (κ = 1.0) and two discordant results for rpoB (κ = 0.82). Considering the 54 cultured strains, very good agreement with gDST was observed for the detection of the 25 distinct mutations in rpoB, katG, and pro-inhA, (κ = 0.95, 0.88, and 0.95, respectively). In conclusion, the automated MDR/MTB ELITe MGB® assay shows great promise and appears to be a valuable tool for rapid detection of pre-MDR- and MDR-TB directly from clinical specimens.


2017 ◽  
Vol 51 (0) ◽  
Author(s):  
Geisa Fregona ◽  
Lorrayne Belique Cosme ◽  
Cláudia Maria Marques Moreira ◽  
José Luis Bussular ◽  
Valdério do Valle Dettoni ◽  
...  

ABSTRACT OBJECTIVE To analyze the prevalence and factors associated with multidrug-resistant tuberculosis in Espírito Santo, Brazil. METHODS This is a cross-sectional study of cases of tuberculosis tested for first-line drugs (isoniazid, rifampicin, pyrazinamide, ethambutol, and streptomycin) in Espírito Santo between 2002 and 2012. We have used laboratory data and registration of cases of tuberculosis – from the Sistema Nacional de Agravos de Notificação and Sistema para Tratamentos Especiais de Tuberculose. Individuals have been classified as resistant and non-resistant and compared in relation to the sociodemographic, clinical, and epidemiological variables. Some variables have been included in a logistic regression model to establish the factors associated with resistance. RESULTS In the study period, 1,669 individuals underwent anti-tuberculosis drug susceptibility testing. Of these individuals, 10.6% showed resistance to any anti-tuberculosis drug. The rate of multidrug resistance observed, that is, to rifampicin and isoniazid, has been 5%. After multiple analysis, we have identified as independent factors associated with resistant tuberculosis: history of previous treatment of tuberculosis [recurrence (OR = 7.72; 95%CI 4.24–14.05) and re-entry after abandonment (OR = 3.91; 95%CI 1.81–8.43)], smoking (OR = 3.93; 95%CI 1.98–7.79), and positive culture for Mycobacterium tuberculosis at the time of notification of the case (OR = 3.22; 95%CI 1.15–8.99). CONCLUSIONS The partnership between tuberculosis control programs and health teams working in the network of Primary Health Care needs to be strengthened. This would allow the identification and monitoring of individuals with a history of previous treatment of tuberculosis and smoking. Moreover, the expansion of the offer of the culture of tuberculosis and anti-tuberculosis drug susceptibility testing would provide greater diagnostic capacity for the resistant types in Espírito Santo.


2014 ◽  
Vol 2014 ◽  
pp. 1-4
Author(s):  
Abdul Hannan ◽  
Saira Munir ◽  
Muhammad Usman Arshad ◽  
Nabila Bashir

Background. Tuberculosis (TB) is a chronic bacterial disease. Mycobacterium tuberculosis, being the leading member of the MTB complex, is the main cause of tuberculosis worldwide. Tuberculosis is managed with combination of drugs: streptomycin, isoniazid, rifampicin, ethambutol, and pyrazinamide. Over the recent past years resistance against first line antituberculous drugs has emerged rapidly throughout the world resulting in MDR strains. The new threat in the management of MDR-TB is the development of resistance against second line drugs: aminoglycosides, polypeptides, fluoroquinolones, and thioamides. Multidrug resistant (MDR) and extensively drug resistant TB (XDR) strains have become a major concern to control TB particularly in the developing countries. The need of the hour is to look for new modalities having antimycobacterial activity. Honey has been well known for its antibacterial activity. We intended to explore its antimycobacterial activity against MDR-TB. Objective. The objective of this study was to determine whether Pakistani Beri honey has any antimycobacterial activity. Method. The study was conducted in the Department of Microbiology, University of Health Sciences, Lahore. Clinical isolates (n=21) of MDR-MTB were evaluated for their susceptibility to Beri honey. The isolates were provided, courtesy of Pakistan Medical Research Council. These isolates were identified by MTBc ID test (Becton & Dickinson) and further tested for their antimycobacterial activity using Beri honey. The honey was tested at the following concentrations (v/v): 1%, 2%, 3%, 4%, and 5% in MGIT 960. Growth controls were also inoculated with each isolate (growth control has no concentration of honey, only containing growth of isolate). Results. MDR-TB isolates (n=21) were tested; 3 (14%) isolates were susceptible at 1% v/v honey, while at 2% v/v of honey 18 (86%) isolates were found to be susceptible. All the 21 isolates (n=21) were susceptible at 3% v/v of honey. Conclusion. The present study clearly demonstrates that Pakistani Beri honey possesses significant antimycobacterial activity in vitro. The antimycobacterial activity of Pakistani Beri honey may, therefore, be exploited in an appropriate mouse model.


2020 ◽  
Vol 6 (4) ◽  
pp. 00329-2020
Author(s):  
Roland Diel ◽  
Albert Nienhaus

BackgroundA total of 5429 new cases of tuberculosis (TB) were reported in Germany in 2018; out of the 3780 TB cases for whom drug susceptibility testing was available, the proportion of multidrug-resistant TB (MDR-TB) cases was only 3.1% (118 cases).MethodsOn the basis of the current therapy guidelines of the German Central Committee against Tuberculosis, this study estimates the mean direct outpatient and combined in- and outpatient costs per non-MDR-TB patient from the perspective of the German statutory health insurance (SHI) system, together with costs arising from productivity losses and costs due to public health screening for TB in close contacts.ResultsFrom the insurance perspective, the mean outpatient costs (rounded) per case were €1628 for adults and €1179 for children for standard therapy; the mean cost of inpatient treatment amounted to €8626. The mean combined inpatient/outpatient cost was €8756 for adults and €8512 for children. As 95% of all TB patients were adults, the weighted treatment cost per patient in Germany in 2018 was €8746. These are in addition to the mean cost arising from productivity losses (€1839) and, weighted by pulmonary infectivity, cost of contact investigations (€368), coming to a total of €10 953.ConclusionGiven the clear increase in the number of non-MDR-TB cases since 2015, TB is still a disease of significant economic impact in Germany.


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