First Line Anti-Tuberculosis Drugs Resistance Patterns of <i>Mycobacterium tuberculosis</i>Isolates from Newly Diagnosed Cases of Tuberculosis

Introduction: Tuberculosis is a major cause of mortality and morbidity world-wide. Anti-tuberculosis drugs have been used for many decades but resistance to them is now widespread. Globally 5% of tuberculosis cases and in India 3% among new TB cases. This study was planned to know the pattern of first line anti-tuberculosis drug resistance in south Gujarat, Surat region in newly diagnosed patients of tuberculosis. Material and Methods: 350 samples were processed for homogenisation and concentration using 4% NAOH-2.9% trisodium citrate. Processed samples were inoculated in liquid medium that is MGIT (Mycobacterial growth indicator tube). Positive samples for M. tbwere processed further for first line anti-tuberculosis drugs sensitivity testing (DST). Reading was taken by using MicroMGIT system. Result: Out of 350 samples 59 (17%) were positive samples, of which 48 (13%) were M. tb and 11 (3%) were non tuberculous mycobacteria. Out of 48 samples 2% (1 isolate) was resistant to isoniazid and Rifampicin while 2% were monoresistant to isoniazide, 2% monoresistant to streptomycin. No rifampicin monoresistant was detected. Conclusion: Such study may help in control of tuberculosis at regional and national level which would in turn help in planning of measures to control Multi-drug resistance tuberculosis. Continuous surveillance should be applied to know the periodic changing patterns and trend in Drug resistant tuberculosis.

Use of Cost Effective Semi-Automated (Mannual/Micro) MGIT System over BACTEC 960 to Perform First Line Anti-Tuberculosis Drugs Sensitivity Testing

Introduction: Multi-drug resistant tuberculosis (MDR-TB) that is the tuberculosis that is resistant to at least 2 of the first line anti-tuberculosis drugs is fatal infectious disease. Cases of MDR-TB are now increasing with 30,000 cases of MDR-TB reported in 2013 by national TB programme. Rapid diagnosis of MDR-TB is extremely important for rapid treatment of patient and to prevent spread of MDR-TB to other. BACTEC 960 system helps in rapid diagnosis but purchase of expensive instrument for the same is the limitation. However, the same purpose can be solved by use of semi-automated MGIT system. Aims and Objectives: Aim of this study is to do drug sensitivity testing of the first line anti-tuberculosis drugs with the use of semi-automated MGIT systems. 350 newly registered and suspected cases of tuberculosis in tertiary care hospital were included. Samples were processed for digestion and decontamination and inoculated in MGIT tubes and also on LJ medium. Reading was taken using semi-automated MGIT system. Positive tubes were confirmed by rapid test for M. tuberculosis and then drug sensitivity was performed. Result: Out of 350 samples, 62% were sputum;33% were pleural fluid and rest 5% were lymph node, Ascetic fluid, CSF, pus. Average day of positivity by MGIT was 13 - 20 days as compared to 25 - 37 days by solid medium, which was statistically significant with p value Conclusion: Manual MGIT System is a simple, efficient, safe to use diagnostic system. It does not require any expensive/special instrumentation other than the UV lamp for detection of fluorescence. The rapidity by which mycobacteria are detected is the most important advantage of the Manual MGIT. In areas with limited resources where purchase of expensive instruments such as the MGIT960 is out of scope, the use of manual MGIT for rapid susceptibility testing for MDR-TB could be a possibility.

NAT2＊6A, a haplotype of the N-acetyltransferase 2 gene, is an important biomarker for risk of anti-tuberculosis drug-induced hepatotoxicity in Japanese patients with tuberculosis

AIM: To investigate an association between N -acetyltransferase 2 (NAT2 )-haplotypes/diplotypes and adverse effects in Japanese pulmonary tuberculosis patients. METHODS: We studied 100 patients with pulmonary TB treated with anti-TB drugs including INH. The frequencies and distributions of single nucleotide polymorphisms, haplotypes, and diplotypes of NAT2 were determined by the PCR-restriction fragment length polymorphism method, and the results were compared between TB patients with and without adverse effect, using multivariate logistic regression analysis.RESULTS: Statistical analysis revealed that the frequency of a variant haplotype, NAT2*6A , was signifi cantly increased in TB patients with hepatotoxicity, compared with those without hepatotoxicity [P = 0.001, odds ratio (OR) = 3.535]. By contrast, the frequency of a wild-type (major) haplotype, "NAT2*4", was signif icantly lower in TB patients with hepatotoxicity than those without hepatotoxicity (P < 0.001, OR = 0.265). There was no association between NAT2-haplotypes and skin rash or eosinophilia. CONCLUSION: The present study shows that NAT2 is one of the determinants of anti-TB drug-induced hepatotoxicity. Moreover, the haplotypes, NAT2*4 and NAT2*6A, are useful new biomarkers for predicting anti- TB drug-induced hepatotoxicity.

Pyrrolidine dithiocarbamate alleviates the anti-tuberculosis drug-induced liver injury through JAK2/STAT3 signaling pathway:An experimental study

Objective:To study the effect of pyrrolidine dithiocarbamate(PDTC) on the anti-tuberculosis drug-induced liver injury and the molecular mechanism. Methods:Clean male SD rats were selected as experimental animals and randomly divided into normal group,model group,PDTC group and AG490 group. Animal model of anti-tuberculosis drug-induced liver injury was established by intragastric administration isoniazid + rifampicin. PDTC group received intraperitoneal injection of PDTC,and AG490 group received intraperitoneal injection of AG490. Twenty-eight days after intervention,the rats were executed,and the liver injury indexes,inflammation indexes and oxidative stress indexes in serum as well as JAK2/STAT3 expression,liver injury indexes,inflammation indexes and oxidative stress indexes in liver tissue were determined. Results:p-JAK2,p-STAT3,TNF-α,IL-1β,IL-6,ROS,8-OHdG and MDA expression in liver tissue as well as TBIL,ALT,AST,γ-GT,TNF-α,IL-1β,IL-6,ROS,8-OHdG and MDA levels in serum of model group were significantly higher than those of normal group while p-JAK2,p-STAT3,TNF-α,IL-1β,IL-6,ROS,8-OHdG and MDA expression in liver tissu as well as TBIL,ALT,AST,γ-GT,TNF-α,IL-1β,IL-6,ROS,8-OHdG and MDA levels in serum of PDTC group and AG490 group were significantly lower than those of model group. Conclusions:PDTC can inhibit the inflammation and oxidative stress mediated by JAK2/STAT3 signaling pathway to alleviate the anti-tuberculosis drug-induced liver injury.

Drug Resistance Pattern in Pulmonary Tuberculosis Patients and Risk Factors Associated with Multi-Drug Resistant Tuberculosis

Introduction: Anti-tuberculosis drug resistance is a major problem in tuberculosis (TB) control programme, particularly multi-drug resistance TB (MDR-TB) in Nepal. Drug resistance is difficult to treat due to its associated cost and side effects. The objective of this study was to assess the drug resistance pattern and assess risk factor associated with MDR-TB among pulmonary tuberculosis patients attending National Tuberculosis Center. Methodology: The comparative cross sectional study was conducted at National Tuberculosis Center during August 2015 to February 2015. Early morning sputum samples were collected from pulmonary tuberculosis suspected patients and subjected to Ziehl-Neelsen staining and fluorochrome staining and culture on Lowenstein-Jensen (LJ) medium. Drug Susceptibility test was performed on culture positive isolates by using proportion method. Univariate and multivariate analysis was computed to assess the risk factors of MDR-TB. Results: Out of 223 sputum samples, 105 were fluorochrome staining positive, 85 were ZN staining positive and 102 were culture positive. Out of 102 culture positive isolates, 37.2% were resistance to any four anti-TB drugs. 11 (28.9%) were initial drug resistance and 28 (43.7%) were acquired drug resistance. The overall prevalence of MDR-TB was 11.7%, of which 2 (5.3%) were initial MDR-TB and 10 (15.6%) were acquired MDR-TB. Univariate and multivariate analysis showed female were significantly associated (P = 0.05) with MDR-TB. Conclusion: Drug resistance TB particularly MDR-TB is high. The most common resistance pattern observed in this study was resistance to both isoniazid and rifampicin. Female were found to be associated with MDR-TB. Thus, early diagnosis of TB and provision of culture and DST are crucial in order to combat the threat of DR-TB.

Research progress on the drug action and resistance mechanism in Mycobacterium tuberculosis

Tuberculosis(TB)is a chronic infectious disease caused by Mycobacterium Tuberculosis(MTB).It is the second largest single cause of death besides novel coronavirus pneumonia.Along with the abuse of antibiotics and extensive use of anti-tuberculosis drugs,multidrug-resistant(MDR)TB,drug-resistant(XDR)TB and totally drug-resistant(TDR)TB became obstacles to the tuberculosis eradication worldwide.According to the World Health Organization(WHO)statistics,China is not only a high burden tuberculosis country in the world,but also a country with a serious epidemic of MDR.Traditional drugs fail to meet the needs of tuberculosis control.Therefore,it is urgent to find new targets of anti-tuberculosis drugs and develop new anti-tuberculosis drugs.Hence,this paper systematically summarizes the mechanism of traditional and newly developed anti-tuberculosis drugs,in which stressing the research progress of drug resistance mechanisms.This work provides us with new insights of new anti-tuberculosis drug developments,and may contribute to a reduction in the harm that tuberculosis brings to society.

Endogenous peroxynitrite activated fluorescent probe for revealing anti-tuberculosis drug induced hepatotoxicity

Py^(+)razinamide (PZA), isoniazid (INH) and rifampicin (RFP) are all commonly used anti-tuberculosis drugs in clinical practice, and long-term medication may cause severe liver damage and toxicity. The level of peroxynitrite (ONOO^(-)) generated in liver has long been regarded as a biomarker for the prediction and measurement of drug-induced liver injury (DILI). In this article, we constructed a BODIPY-based fluorescent probe (BDP-Py^(+)) that enabled quickly and sensitively detect and image ONOO^(-) in vivo. Utilizing this probe, we demonstrated the change of ONOO^(-) content in cells and mice model of DILI induced by acetaminophen (APAP), and for the first time revealed the mechanism of liver injury induced by antituberculosis drug PZA. Moreover, BDP-Py^(+) could be applied to screen out and evaluate the hepatotoxicity of different anti-tuberculosis drugs. Comparing with the existing serum enzymes detection and H&E staining, the probe could achieve early diagnosis of DILI before solid lesions in liver via monitoring the up-regulation of ONOO^(-) levels. Collectively, this work will promote the understanding of the pathogenesis of anti-tuberculosis drug induced liver injury (ATB-DILI), and provide a powerful tool for the early diagnosis and treatment of DILI.

Helicobacter pylori eradication with moxifloxacin-containing therapy following failed first-line therapies in South korea

AIM: To investigate moxifloxacin-containing triple therapy as second-line treatment for Helicobacter pylori (H. pylori) infection following failed first-line treatment.

The production and sales of antituberculosis drugs in China

Background:Tuberculosis(TB)is a major infectious disease globally.Adequate and proper use of anti-TB drugs is essential for TB control.This study aims to study China’s production capacity and sales situation of anti-TB drugs,and to further discuss the potential for China to contribute to global TB control.Methods:The production data of anti-TB drugs in China from 2011 to 2013 and the sales data from 2010 to 2014 were extracted from Ministry of Industry and Information Technology database of China and IMS Health database,respectively.The number of drugs was standardized to the molecular level of the key components before calculating.All data were described and analyzed by Microsoft Excel.Results:First-line drugs were the majority in both sales(89.5%)and production(92.3%)of anti-TB drugs in China.The production of rifampicin held the majority share in active pharmaceutical ingredients(APIs)and finished products,whilst ethambutol and pyrazinamide were the top two sales in finished products.Fixed-dose combinations only held small percentages in total production and sales weight,though a slight increase was observed.The production and sales of streptomycin showed a tendency of decrease after 2012.The trends and proportion of different anti-TB drugs were similar in production and sales,however,the production weight was much larger than that of sales,especially for rifampicin and isoniazid.Conclusions:First-line drugs were the predominant medicine produced and used in China.While the low production and sales of the second-line TB drugs and FDCs rose concerns for the treatment of multiple drug resistant TB.The redundant production amount,as well as the prompt influence of national policy on drug production and sales,indicated the potential for China to better contribute to global TB control.

Clinical Response to Treatment of Central Nervous System Tuberculosis in Non-Human Immunodeficiency Virus-Infected Adolescents and Adults

Introduction: More than half of patients with central nervous system tuberculosis (CNS TB) die or are left with severe neurological deficits despite receiving anti-TB treatment. Aims of the study: This study examined risk factors associated with poor response to initial treatment with four anti-TB drug regimens or three drug regimens with steroids as adjuvant therapy. Methods: This study analyzed medical records from two tertiary hospitals in Busan, Korea, between January 2009 and March 2012. The subjects were non-human immunodeficiency virus (HIV)-infected patients aged ≥16 years with clinical CNS TB. The subjects were divided into two groups according to response to treatment. Results: In totally, 52 patients with CNS TB were included. Of these, 14 (26%) and 38 (73%) showed poor and good responses, respectively. Of the patients with poor response, nine had stage III disease (64.3%) according to the British Medical Research Council (BMRC) staging system. A significantly higher proportion was seen in the good response group (p < 0.05). Patients with positive cerebrospinal fluid (CSF) acid-fast bacillus (AFB) culture, positive sputum AFB culture, positive CSF TB polymerase chain reaction (PCR) results, and brain tuberculoma had poorer responses (p < 0.05). Multivariate analysis to determine risk factors associated with poor response to anti-TB therapy revealed that a poor response was associated with stage III clinical signs upon diagnosis (odds ratio [OR] 32.122;95% confidence interval [CI] 2.221 - 464.605), positive sputum AFB culture (OR 13.624;95% CI 1.066 - 174.149), and tuberculoma on brain images (OR 45.714;95% CI 1.893 - 1104.018). Conclusions: The results demonstrate the importance of identifying the severity of CNS TB and promptly administering anti-TB drugs. It is necessary to perform drug susceptibility testing for anti-TB drugs. Further studies are needed to confirm the correlations between risk factors associated with poor response and anti-TB drug resistance and the other risk factors.

Establishment and application of the screening model of the Mycobacterium tuberculosis β-lactamase BlaC inhibitors

With the continuous emergence and rapid spread of multidrug-resistant and extensively-drug-resistant Mycobacterium tuberculosis strains, it is imperative to develop novel therapies against this bacterium. The intrinsic β-lactam resistance of M. tuberculosis is primarily due to the production of an Ambler class-A β-lactamase BlaC, which limits the application of β-lactam antibiotics in the treatment of tuberculosis. Therefore, the inhibitors of BlaC could be novel anti-tuberculosis drug synergistic agents to recover the sensibility of M. Tuberculosis to the β-lactam antibiotics. In the present study, BlaC of M. tuberculosis was expressed and purified to establish a screening model of the BlaC inhibitors. The screening conditions were determined, and the screening model was evaluated to fit for the high throughput screening. A total of 22 BlaC inhibitors were screened out from 26 400 compound samples with a positive rate of 0.083%. Taken together, our findings lay the foundation for the discovery of novel anti-tuberculosis drug synergistic agents in clinic.