Multidrug-resistant Tuberculosis Treatment Outcomes Research Articles

The relationship between social support, treatment interruption and treatment outcome in patients with multidrug-resistant tuberculosis in China: a mixed-methods study.

Multidrug-resistant tuberculosis (MDR-TB) has been a major threat for successful TB control. We examined the relationship between social support and treatment outcomes in MDR-TB patients and evaluated barriers to social support. Retrospective cohort study with MDR-TB patients enrolled in the Global Fund programme between 1 January 2009 and 30 June 2014 in Zhejiang, China. We reviewed all MDR-TB patients' diagnoses and treatment outcomes. In-depth interviews were conducted with 10 community health workers and 10 patients. Pathway analysis was employed to examine the association between social support and treatment outcomes, and the mediating effect of medication adherence on their relationship. Of 218 participants, 144 (66%) were successfully treated and 59 (27%) had poor treatment adherence. Directly observed therapy (DOT) had an indirect positive effect on treatment success, mediating through medication adherence (β=0.541, P=0.008; β=0.538, P<0.001). Financial support had both a direct (β=0.769, P<0.001) and an indirect positive effect on treatment success, which was mediated by a self-reported social support scale (β=0.541, P=0.008; β=0.538, P<0.001). The interviews indicated poor performance of DOT. Patients often suffered from substantial stigma, but were not provided with psychological support. DOT and financial support were effective strategies for improving successful treatment outcomes in MDR-TB patients, but they were delivered not considering patients' perspectives. There is an urgent need for consistent and specific psychological support for MDR-TB patients in their communities.

Impact of pyrazinamide resistance on multidrug-resistant tuberculosis in Karakalpakstan, Uzbekistan.

The World Health Organization (WHO) recommends the inclusion of pyrazinamide (PZA) in treatment regimens for multidrug-resistant tuberculosis (MDR-TB) unless resistance has been confirmed. To investigate the association between PZA susceptibility and MDR-TB treatment outcome among patients treated with a PZA-containing regimen and whether the duration of the intensive phase of the PZA-containing regimen affected treatment outcome. We conducted a retrospective cohort study including all eligible MDR-TB patients starting treatment in 2003-2013 in the TB programme in Karakalpakstan, Uzbekistan. PZA drug susceptibility testing (DST) using liquid culture was performed, and outcomes were classified according to the WHO 2013 definitions. Of 2446 MDR-TB patients included, 832 (34.0%) had an available baseline PZA DST result, 612 (73.6%) of whom were PZA-resistant. We found no association between treatment success and PZA susceptibility (adjusted odds ratio [aOR] 0.86, 95%CI 0.51-1.44, P = 0.6) in patients treated with PZA. Furthermore, among patients with no baseline PZA DST result, no evidence was seen of an association between treatment success and PZA treatment duration (aOR 0.86, 95%CI 0.49-1.51, P = 0.6). Treatment of MDR-TB with a standard PZA regimen does not appear to improve treatment outcomes, regardless of PZA susceptibility or duration of treatment.

Drug‐resistant tuberculosis: An update on disease burden, diagnosis and treatment

The emergence of antimicrobial resistance against Mycobacterium tuberculosis, the leading cause of mortality due to a single microbial pathogen worldwide, represents a growing threat to public health and economic growth. The global burden of multidrug-resistant tuberculosis (MDR-TB) has recently increased by an annual rate of more than 20%. According to the World Health Organization approximately only half of all patients treated for MDR-TB achieved a successful outcome. For many years, patients with drug-resistant tuberculosis (TB) have received standardized treatment regimens, thereby accelerating the development of MDR-TB through drug-specific resistance amplification. Comprehensive drug susceptibility testing (phenotypic and/or genotypic) is necessary to inform physicians about the best drugs to treat individual patients with tailor-made treatment regimens. Phenotypic drug resistance can now often, but with variable sensitivity, be predicted by molecular drug susceptibility testing based on whole genome sequencing, which in the future could become an affordable method for the guidance of treatment decisions, especially in high-burden/resource-limited settings. More recently, MDR-TB treatment outcomes have dramatically improved with the use of bedaquiline-based regimens. Ongoing clinical trials with novel and repurposed drugs will potentially further improve cure-rates, and may substantially decrease the duration of MDR-TB treatment necessary to achieve relapse-free cure.

Factors affecting time to sputum culture conversion and treatment outcome of patients with multidrug-resistant tuberculosis in China

BackgroundFew prospective cohort studies, none in China, have investigated the relationship between treatment outcomes of multidrug-resistant tuberculosis (MDR-TB) patients and sputum culture conversion. Factors affecting the time of the culture conversion throughout the whole course of the treatment have rarely been investigated.MethodsThis study was performed in four cities in Jiangsu province, China. MDR-TB patients were consecutively enrolled between December 2011 and March 2014. Rates of sputum culture conversion were calculated and Cox proportional-hazards model was performed. Factors contributing to sputum culture conversion were investigated.ResultsIn all, 139 MDR-TB patients with treatment outcomes were enrolled. Median time to culture conversion among those who converted was 91.5 days (interquartile range, 34.0–110.8 days). After multivariable analysis, smoking (HR = 0.44; 95% CI: 0.23–0.83), drinking (HR = 0.41; 95% CI: 0.21–0.81), ofloxacin resistance (HR = 0.43; 95% CI: 0.24–0.76) and sputum smear grade > 1 (HR = 0.51; 95% CI: 0.31–0.83) were less likely to have culture conversion.ConclusionsMDR-TB patients who smoke, drink, have ofloxacin resistance, or a high smear grade are less likely to respond to treatment and should be meticulously followed up.

Treatment Outcomes of Multidrug-Resistant Tuberculosis in Taiwan: Tackling Loss to Follow-up.

The proportion of treatment success among patients with multidrug-resistant tuberculosis (MDR-TB) enrolled between 1992 and 1996 was 51.2%, and that among patients enrolled between 2000 and April 2007 was 61%. To address the challenge of MDR-TB, the Taiwan MDR-TB Consortium (TMTC) was established in May 2007. To assess the performance of the TMTC, we analyzed the data of patients enrolled in its first 5 years. Comprehensive care was provided at no cost to patients, who were usually hospitalized for 1 month initially. Treatment regimens consisted of 4-5 drugs and the duration of treatment was 18-24 months. A case manager and a directly observed therapy provider were assigned to each patient. Psychosocial support was provided to address emotional stress and stigma. Financial support was offered to avoid the financial hardship faced by patients and their families. We assessed treatment outcomes at 30 months using internationally recommended outcome definitions. Of the 692 MDR-TB patients, 570 (82.4%) were successfully treated, 84 (12.1%) died, 18 (2.6%) had treatment failure, and 20 (2.9%) were lost to follow-up. Age ≥65 years (adjusted odds ratio [aOR], 6.78 [95% confidence interval {CI}, 3.14-14.63]), cancer (aOR, 11.82 [95% CI, 5.55-25.18]), and chronic kidney disease (aOR, 3.62 [95% CI, 1.70-7.71]) were significantly associated with death. Resistance to fluoroquinolone (aOR, 10.89 [95% CI, 3.97-29.88]) was significantly associated with treatment failure. The TMTC, which operates under a strong collaboration between the public health authority and clinical teams, has been a highly effective model of care in the management of MDR-TB.

Limited Effect of Later-Generation Fluoroquinolones in the Treatment of Ofloxacin-Resistant and Moxifloxacin-Susceptible Multidrug-Resistant Tuberculosis.

Recent data conflict on the clinical efficacy of later-generation fluoroquinolones, such as moxifloxacin or levofloxacin, for the treatment of multidrug-resistant tuberculosis (MDR-TB) that is resistant to ofloxacin but susceptible to moxifloxacin. The purpose of the present study was to evaluate whether later-generation fluoroquinolones can improve treatment outcomes in patients with ofloxacin-resistant, moxifloxacin-susceptible MDR-TB. A retrospective cohort study was performed on 208 patients with moxifloxacin-susceptible MDR-TB who were treated between 2006 and 2011. Later-generation fluoroquinolones were used for all patients. Overall, 171 patients (82%) had ofloxacin-susceptible, moxifloxacin-susceptible MDR-TB (ofloxacin-susceptible group), and 37 (18%) had ofloxacin-resistant, moxifloxacin-susceptible MDR-TB (ofloxacin-resistant group). Compared to the ofloxacin-susceptible group, the ofloxacin-resistant group was more likely to have a history of MDR-TB treatment (P < 0.001) and cavitary lesions on chest radiography (P < 0.001). In addition, the ofloxacin-resistant group was more likely than the ofloxacin-susceptible group to have resistance to the drugs pyrazinamide (P = 0.003), streptomycin (P = 0.015), prothionamide (P < 0.001), and para-aminosalicylic acid (P < 0.001). Favorable outcomes were more frequently achieved for the ofloxacin-susceptible group than for the ofloxacin-resistant group (91% [156/171] versus 57% [21/37], respectively [P < 0.001]). In multivariable regression logistic analysis, the ofloxacin-susceptible group was about 5.36 (95% confidence interval, 1.55 to 18.53) times more likely than the ofloxacin-resistant group (P < 0.001) to have favorable outcomes. Despite in vitro moxifloxacin susceptibility, the frequency of favorable treatment outcomes for ofloxacin-resistant MDR-TB was significantly lower than that for ofloxacin-susceptible MDR-TB, even when later-generation fluoroquinolones were used, indicating that more-aggressive therapies may be needed for ofloxacin-resistant MDR-TB.

Treatment Outcomes of Multi-Drug-Resistant Tuberculosis and Its Determinants in Boru Meda Hospital, Northeast Ethiopia

Background: Multidrug-resistant tuberculosis remains a peril to the global tuberculosis control struggle. Ethiopia is one of the high burden countries and tuberculosis remains one of the leading causes of mortality. The prolonged treatment associated with multi-drug resistance tuberculosis and the often-severe adverse effects of second-line anti-tuberculosis agents increases the challenges to achieve treatment completion.Objectives: The aim of this study is to assess the treatment outcomes of multidrug-resistant tuberculosis management and its determinants in Boru Meda Hospital.Methods: A retrospective cohort study was employed for this study. All patients enrolled for multidrug-resistant tuberculosis management between December 2012 and 2016 were included in the study. Interim and final outcomes of multidrug-resistant tuberculosis treatment were collected from the multidrug-resistant tuberculosis registry. The demographic and clinical characteristics of cases, drug resistance and the treatment regimen, management and outcome were described. Chi-square test was used to calculate association factors with a successful treatment outcome.Result: Totally, 141 patients were included for the study from December 18, 2012–June 7, 2016. Women were slightly greater than men patients, 53.2%. The mean age of the study participants was 30.87 years. Majority of the patients, 84.4%, had favorable interim treatment out come at the end of six month. Totally, 61.1% patients were cured, 24.4% of them died, 8.9% were defaulted, 3.3% have completed, and 2.2% failed. Patients in the age group of ≤ 18 years and 19-29 years, and patients having a negative culture result by six month were associated with successful treatment outcome.Conclusion and recommendation: The cure rate was about 60% and significant number of patients were died (24.4%). Strategies to reduce defaulters are crucial in the treatment of multidrug-resistant tuberculosis. The current results indicate that special attention should be paid to older patients.

Sputum bacteriology conversion and treatment outcome of patients with multidrug-resistant tuberculosis.

PurposeMultidrug-resistant tuberculosis (MDR-TB) requires long-term treatment, has a high fatality rate, and constitutes a global threat. Earlier detection of treatment failure is required to predict therapeutic efficacy.Patients and methodsWe enrolled MDR-TB patients consecutively from January 2011 through December 2012 in Lianyungang, China. Sputum smear microscopy tests and sputum cultures were performed once a month for the first 6 months following initiation of antituberculosis treatment and once every 2 months thereafter until the end of therapy. The sensitivity, specificity and area under the receiver operating characteristic curve (AUC) were used with a 95% CI to estimate the role of sputum bacteriology conversion in predicting treatment outcomes.ResultsAmong the 92 MDR-TB patients enrolled in this study, 40.2% had poor treatment outcomes. The median initial sputum bacteriology conversion time was 1 month. Patients having 2-month sputum smear conversions (adjusted odds ratio [OR]: 7.19, 95% CI: 2.60–19.84) or culture conversions (adjusted OR: 2.88, 95% CI: 1.11–7.45) were more likely to experience good outcomes. The sensitivity and specificity obtained when using two-month sputum smear conversions to predict treatment outcomes were 67.6% (95% CI: 50.2–82.0) and 76.4% (95% CI: 63.0–86.8), respectively. The sensitivity and specificity obtained when using 2-month culture conversions to predict treatment outcomes were 48.6% (95% CI: 32.0–65.6) and 74.5% (95% CI: 61.0–85.3), respectively. The AUC for two-month smear conversions was 0.72 (95% CI: 0.62–0.81), significantly higher than that obtained for 2-month culture conversions (0.62, 95% CI: 0.52–0.72) (χ2 = 4.18, P = 0.041).ConclusionThe prognoses of MDR-TB patients displaying persistent sputum positivity were inferior to those for whom sputum bacteriology conversion was observed. Thus, sputum smear conversion results obtained 2 months after treatment initiation may provide a potential means for predicting MDR-TB treatment outcomes.

Improved Survival and Cure Rates With Concurrent Treatment for Multidrug-Resistant Tuberculosis-Human Immunodeficiency Virus Coinfection in South Africa.

Mortality in multidrug-resistant (MDR) tuberculosis-human immunodeficiency virus (HIV) coinfection has historically been high, but most studies predated the availability of antiretroviral therapy (ART). We prospectively compared survival and treatment outcomes in MDR tuberculosis-HIV-coinfected patients on ART to those in patients with MDR tuberculosis alone. This observational study enrolled culture-confirmed MDR tuberculosis patients with and without HIV in South Africa between 2011 and 2013. Participants received standardized MDR tuberculosis and HIV regimens and were followed monthly for treatment response, adverse events, and adherence. The primary outcome was survival. Among 206 participants, 150 were HIV infected, 131 (64%) were female, and the median age was 33 years (interquartile range [IQR], 26-41). Of the 191 participants with a final MDR tuberculosis outcome, 130 (73%) were cured or completed treatment, which did not differ by HIV status (P = .50). After 2 years, CD4 count increased a median of 140 cells/mm3 (P = .005), and 64% had an undetectable HIV viral load. HIV-infected and HIV-uninfected participants had high rates of survival (86% and 94%, respectively; P = .34). The strongest risk factor for mortality was having a CD4 count ≤100 cells/mm3 (adjusted hazards ratio, 15.6; 95% confidence interval, 4.4-55.6). Survival and treatment outcomes among MDR tuberculosis-HIV individuals receiving concurrent ART approached those of HIV-uninfected patients. The greatest risk of death was among HIV-infected individuals with CD4 counts ≤100 cells/mm3. These findings provide critical evidence to support concurrent treatment of MDR tuberculosis and HIV.

MULTIDRUG‐RESISTANT TUBERCULOSIS TREATMENT OUTCOME: TERTIARY CENTER EXPERIENCE

RespirologyVolume 22, Issue S3 p. 63-63 Tuberculosis 3 MULTIDRUG-RESISTANT TUBERCULOSIS TREATMENT OUTCOME: TERTIARY CENTER EXPERIENCE First published: 23 November 2017 https://doi.org/10.1111/resp.13206_156Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume22, IssueS3Supplement: 22nd Congress of the Asian Pacific Society of Respirology, International Convention Centre, Sydney, Australia, 23–26 November 2017November 2017Pages 63-63 RelatedInformation

Cost effectiveness of decentralised care model for managing MDR-TB in India

BackgroundIn India, multidrug-resistant tuberculosis (MDR-TB) patients are usually treated in hospitals. Decentralised care model, however, has been suggested as a possible alternative by the World Health Organization (WHO). In the “End TB Strategy”, the WHO highlights, as one of the key targets for 2035, that ‘no TB-affected families should face catastrophic hardship due to the tuberculosis’. Removal of financial barriers to health-care access and mitigation of catastrophic expenditures are therefore considered vital to achieve the universal health coverage (UHC) goal. Since forgoing healthcare due to the financial constraints is a known fact in India, decentralised care as an intervention choice (as against hospital-based care) might enhance equity provided it is an affordable choice. Thus, an economic evaluation was conducted, from the perspective of the national health system in India, to assess the cost-effectiveness of decentralised care compared to centralised care for MDR-TB. MethodsThis study uses a decision-analytic model with a follow-up of two years to assess the expected costs of the decentralised versus the centralised approaches for MDR-TB treatment. A published systematic review of observational studies yielded the MDR-TB treatment outcomes, which included treatment success, treatment default, treatment failure, and mortality parameters. It was observed that these parameters did not vary significantly between the two alternatives. Treatment costs included the following costs: hospital admission costs, clinic costs, visits to laboratory and MDR-TB centre, drug therapy, injections and food. Costs data of drugs, diagnosis, hospital stay and travel to public facilities, based on a simple market survey, were taken from a recently published study on MDR-TB expenditures in the Chhattisgarh state of India. Potential cost savings related to the implementation of decentralised MDR-TB care for all patients who initiated MDR-TB treatment in India were additionally estimated. ResultsEstimated average expected total treatment cost was US$ 3390.56 for the hospital-based model and US$ 1724.1 for the decentralised model for a patient treated for MDR-TB in India, generating potential savings of US$1666.50 per case, with ICER US$ 2382.68 per QALY gained. One of the primary drivers of this difference was the significantly more intensive (thus expensive) stay charges in the hospital. If the costs and treatment probabilities are extrapolated to the whole country, with 48114 MDR-TB patients initiated on treatment in 2017, decentralised care would have additional 1058 patients cured, gain additional 3824 QALYs, and avert 2165 deaths, as compared to centralised care, in India. At various scenarios of coverage rates of decentralised and centralised care the cost difference would range between 23% and 94% for the country. ConclusionOur study provides evidence of cost savings for MDR-TB patients if patients choose decentralised treatment in comparison to suggested hospitalisation of these patients for centralised treatment with similar outcomes. The economic evaluation presented in this study expected significant efficiency gains in choice of two treatment options and the cost savings may improve equity. In India, treatment of MDR-TB using decentralised care is expected to result in similar patient outcomes at markedly reduced public health costs compared with centralised care.

Mental disorders and drug/alcohol use in patients commencing extensively drug-resistant tuberculosis treatment.

Mental disorders and alcohol/drug use worsen treatment outcomes for multidrug-resistant tuberculosis (TB), but data are lacking for extensively drug-resistant (XDR) TB. We investigated the association of baseline mental disorders and alcohol/drug use on XDR-TB treatment outcomes in a retrospective study of 53 XDR-TB Peruvian patients during 2010-2012. Logistic regression estimated the odds ratios for unfavourable XDR-TB treatment outcomes. Overall treatment success was 25%. Mental disorders and drug/alcohol use were found in respectively 22.4% and 20.4% of patients; neither were associated with unfavourable treatment outcomes. Future research should explore the relationship between mental health and drug/alcohol use in XDR-TB treatment outcomes.

Population pharmacokinetics of moxifloxacin, cycloserine, p-aminosalicylic acid and kanamycin for the treatment of multi-drug-resistant tuberculosis.

Control of multi-drug-resistant tuberculosis (MDR-TB) requires extensive, supervised chemotherapy because second-line anti-TB drugs have a narrower therapeutic range than first-line drugs. This study aimed to develop population pharmacokinetic (PK) models for second-line drugs in patients with MDR-TB, evaluate the recommended dosage regimens and, if necessary, suggest new dosage regimens. A prospective, single-centre PK study was performed on second-line anti-TB drugs in patients with MDR-TB. Moxifloxacin, cycloserine, p-aminosalicylic acid (PAS), kanamycin and other second-line drugs were administered to the patients. Plasma concentrations were analysed using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Population PK models were developed using non-linear mixed effect modelling (NONMEM, Version 7.30; ICON Development Solutions, Ellicott City, MD, USA). Simulations were performed using the calculated PK parameters. The respective absorption rate constant, apparent clearance and apparent volume of distribution values were as follows: 0.305/h, 9.37 L/h and 56.7 L for moxifloxacin; 0.135/h, 1.38 L/h and 10.5 L for cycloserine; 0.510/h, 30.8 L/h and 79.4 L for PAS; and 1.67/h, 3.75 L/h and 15.2 L for kanamycin. The simulations showed that the following dosage regimens were more likely to be within the recommended concentration ranges than the raw data in this study: 200 mg of moxifloxacin once daily (QD) (patient weight <50 kg) and 400 mg of moxifloxacin QD (patient weight ≥50 kg), 500-750 mg of cycloserine QD, 4.95-6.6 g of PAS twice daily and 750-1000 mg of intramuscular kanamycin QD. These findings indicate that the recommended doses should be revised to improve the clinical outcomes of MDR-TB treatment.

Substitution of ethambutol with linezolid during the intensive phase of treatment of pulmonary tuberculosis: study protocol for a prospective, multicenter, randomized, open-label, phase II trial

BackgroundLinezolid, an oxazolidinone, substantially improves treatment outcomes of multidrug-resistant tuberculosis and extensively drug-resistant tuberculosis. We started a trial to test whether the use of linezolid instead of ethambutol could increase the rate of sputum culture conversion as of 8 weeks of treatment in patients with drug-susceptible tuberculosis.Methods/designThis is a phase II, multicenter, randomized study with three arms. We are enrolling patients with pulmonary tuberculosis without rifampicin resistance screened by the Xpert MTB/RIF® assay. The standard treatment arm uses isoniazid (6 months), rifampicin (6 months), pyrazinamide (2 months), and ethambutol (2 months). Experimental arm 1 uses linezolid (600 mg/day) for 4 weeks instead of ethambutol. Experimental arm 2 uses linezolid (600 mg/day) for 2 weeks instead of ethambutol. The primary outcome is the sputum culture conversion rate on liquid media after 2 months of treatment. Secondary outcomes include the sputum culture conversion rate on solid media after 2 months of treatment, time to sputum culture conversion on liquid and solid media, cure rate, and treatment success rate. The frequencies of total adverse events (AEs) and serious AEs will be described and documented. Based on an α = 0.05 level of significance, a power of 85%, a 15% difference in the culture conversion rate after 2 months between the control arm and experimental arm 1 (75% vs. 90%), a 10% default (loss to follow-up) rate, and a 10% culture failure, the required number per arm was calculated to be 143 (429 in total).DiscussionThis trial will reveal the effectiveness and safety of 2 or 4 weeks of use of linezolid instead of ethambutol for patients with drug-susceptible pulmonary tuberculosis. If a new regimen including linezolid shows a higher culture conversion rate by week 8, and is safe, it could be tested as a 4-month antituberculosis treatment regimen in the future.Trial registrationClincalTrials.gov, NCT01994460. Registered on 13 November 2013.

Risk factors for poor multidrug-resistant tuberculosis treatment outcomes in Kyiv Oblast, Ukraine

BackgroundUkraine is among ten countries with the highest burden of multidrug- resistant TB (MDR-TB) worldwide. Treatment success rates for MDR-TB in Ukraine remain below global success rates as reported by the World Health Organization. Few studies have evaluated predictors of poor MDR-TB outcomes in Ukraine.MethodsWe conducted a retrospective analysis of patients initiated on MDR-TB treatment in the Kyiv Oblast of Ukraine between January 01, 2012 and March 31st, 2015. We defined good treatment outcomes as cure or completion and categorized poor outcomes among those who died, failed treatment or defaulted. We used logistic regression analyses to identify baseline patient characteristics associated with poor MDR-TB treatment outcomes.ResultsAmong 360 patients, 65 (18.1%) achieved treatment cure or completion while 131 (36.4%) died, 115 (31.9%) defaulted, and 37 (10.3%) failed treatment. In the multivariate analysis, the strongest baseline predictors of poor outcomes were HIV infection without anti-retroviral therapy (ART) initiation (aOR 10.07; 95% CI 1.20–84.45; p 0.03) and presence of extensively-drug resistant TB (aOR 9.19; 95% CI 1.17–72.06; p 0.03). HIV-positive patients initiated on ART were not at increased risk of poor outcomes (aOR 1.43; 95% CI 0.58–3.54; p 0.44). There was no statistically significant difference in risk of poor outcomes among patients who received baseline molecular testing with Gene Xpert compared to those who were not tested (aOR 1.31; 95% CI 0.63–2.73).ConclusionsRigorous compliance with national guidelines recommending prompt initiation of ART among HIV/TB co-infected patients and use of drug susceptibility testing results to construct treatment regimens can have a major impact on improving MDR-TB treatment outcomes in Ukraine.

Treatment outcomes for multidrug-resistant tuberculosis under DOTS-Plus: a systematic review and meta-analysis of published studies

BackgroundAnti-tuberculosis drug resistance is a major public health problem that threatens the progress made in tuberculosis care and control worldwide. Treatment success rates of multidrug-resistant tuberculosis (MDR-TB) is a key issue that cannot be ignored. There is a paucity of evidence that assessed studies on the treatment of MDR-TB, which focus on the effectiveness of the directly observed treatment, short-course (DOTS)-Plus program. Therefore, it is crucial to assess and summarize the overall treatment outcomes for MDR-TB patients enrolled in the DOTS-Plus program in recent years. The purpose of this study was to thus assess and summarize the available evidence for MDR-TB treatment outcomes under DOTS-Plus.MethodsA systematic review and meta-analysis of published literature was conducted. Original studies were identified using the databases MEDLINE®/PubMed®, Hinari, and Google Scholar. Heterogeneity across studies was assessed using the Cochran’s Q test and I2 statistic. Pooled estimates of treatment outcomes were computed using the random effect model.ResultsBased on the 14 observational studies included in the meta-analysis, it was determined that 5 047 patients reported treatment outcomes. Of these, the pooled prevalence, 63.5% (95% CI: 58.4–68.5%) successfully completed full treatment (cured or treatment completed) with a pooled cure rate of 55.6%, whereas 12.6% (95% CI: 9.0–16.2%) of the patients died, 14.2% (95% CI: 11.6–16.8%) defaulted from therapy, and 7.6% (95% CI: 5.6–9.7%) failed therapy. Overall 35.4% (95% CI: 30–40.8%) of patients had unsuccessful treatment outcomes. An unsatisfactorily high percentage 43% (95% CI: 32–54%) of unsuccessful treatment outcomes was observed among patients who were enrolled in standardized treatment regimens.ConclusionThis study revealed that patients with MDR-TB exhibited a very low treatment success rate compared to the World Health Organization 2015 target of at least 75 to 90%. The high default rate observed by conducting this literature review could possibly explain the spread of the MDR-TB strain in various populations. A better treatment success rate was observed among patients in individualized treatment regimens than in standardized ones. Conducting further individual-based meta-analysis is recommended to identify potential factors for defaulting treatment using large-scale and multi-center studies.

WHO Treatment Guidelines for Drug-Resistant Tuberculosis, 2016 Update: Applicability in South Korea.

Despite progress made in tuberculosis control worldwide, the disease burden and treatment outcome of multidrug-resistant tuberculosis (MDR-TB) patients have remained virtually unchanged. In 2016, the World Health Organization released new guidelines for the management of MDR-TB. The guidelines are intended to improve detection rate and treatment outcome for MDR-TB through novel, rapid molecular testing and shorter treatment regimens. Key changes include the introduction of a new, shorter MDR-TB treatment regimen, a new classification of medicines and updated recommendations for the conventional MDR-TB regimen. This paper will review these key changes and discuss the potential issues with regard to the implementation of these guidelines in South Korea.

PncA mutations are associated with slower sputum conversion during standard treatment of multidrug-resistant tuberculosis

Despite the strong association between drug resistance and genetic mutations, the value of molecular diagnosis of drug resistance to guide the treatment of multidrug-resistant tuberculosis (MDR-TB) remains unclear. This is particularly relevant in resource-limited areas where it is difficult to perform drug susceptibility testing (DST). Here we investigated the association between drug susceptibility phenotypes and genotypes and treatment outcomes in patients with MDR-TB. This study enrolled 74 consecutive patients with confirmed MDR-TB between 2010 and 2011, and outcomes were followed-up over the 24-month treatment course. All of the isolates were tested for phenotypic susceptibility to second-line drugs using the Mycobacteria Growth Indicator Tube (MGIT)-based system, and genotypic mutations were assessed by DNA sequencing. Among the 74 MDR-TB isolates, 29 (39.2%) were resistant to fluoroquinolones and/or second-line injectable drugs, of which 21 (72.4%) harboured a mutation in drug resistance-related genes (gyrA, rrs or eis). In addition, 32 individuals (43.2%) also had pyrazinamide (PZA)-resistant isolates, with 28 (87.5%) containing the pncA mutation. By backward selection in the multivariate logistic regression and Cox proportional hazard models, PZA resistance and its related pncA gene mutation demonstrated a correlation with a lower likelihood of culture conversion at 8 weeks and treatment success. Meanwhile, the fluoroquinolone resistance-related gyrA gene mutation was negatively correlated with treatment success. DST for PZA and fluoroquinolones together with genetic information appears to provide a clinically useful indicator of the treatment outcome of MDR-TB in China.

New Antituberculosis Drugs: From Clinical Trial to Programmatic Use.

Treatment of multidrug-resistant tuberculosis (MDR-TB) cases is challenging because it relies on second-line drugs that are less potent and more toxic than those used in the clinical management of drug-susceptible TB. Moreover, treatment outcomes for MDR-TB are generally poor compared to drug sensitive disease, highlighting the need for of new drugs. For the first time in more than 50 years, two new anti-TB drugs were approved and released. Bedaquiline is a first-in-class diarylquinoline compound that showed durable culture conversion at 24 weeks in phase IIb trials. Delamanid is the first drug of the nitroimidazole class to enter clinical practice. Similarly to bedaquiline results of phase IIb studies showed increased sputum-culture conversion at 2 months and better final treatment outcomes in patients with MDR-TB. Among repurposed drugs linezolid and carbapenems may represent a valuable drug to treat cases of MDR and extensively drug-resistant TB. The recommended regimen for MDR-TB is the combination of at least four drugs to which M. tuberculosis is likely to be susceptible for the duration of 20 months. Drugs are chosen with a stepwise selection process through five groups on the basis of efficacy, safety, and cost. Clinical phase III trials on new regimen are ongoing that could prove transformative against MDR-TB, by being shorter (six months), simpler (an all-oral regimen) and safer than current standard therapy. It is fundamental that the adoption of the new drugs is done responsibly to avoid inappropriate use. Concentration of in-patient MDR-TB treatment in specialized centers could be considered in countries with low numbers of cases in order to provide appropriate clinical case management and to prevent emergence of drug resistance.

Determination of MIC Breakpoints for Second-Line Drugs Associated with Clinical Outcomes in Multidrug-Resistant Tuberculosis Treatment in China.

Our study aims to identify the clinical breakpoints (CBPs) of second-line drugs (SLDs) above which standard therapy fails in order to improve multidrug-resistant tuberculosis (MDR-TB) treatment. MICs of SLDs were determined for M. tuberculosis isolates cultured from 207 MDR-TB patients in a prospective cohort study in China between January 2010 and December 2012. Classification and regression tree (CART) analysis was used to identify the CBPs predictive of treatment outcome. Of the 207 MDR-TB isolates included in the present study, the proportion of isolates above the critical concentration recommended by WHO ranged from 5.3% in pyrazinamide to 62.8% in amikacin. By selecting pyrazinamide as the primary node (CBP, 18.75 mg/liter), 72.1% of sputum culture conversions at month four could be predicted. As for treatment outcome, pyrazinamide (CBP, 37.5 mg/liter) was selected as the primary node to predict 89% of the treatment success, followed by ofloxacin (CBP, 3 mg/liter), improving the predictive capacity of the primary node by 10.6%. Adjusted by identified confounders, the CART-derived pyrazinamide CBP remained the strongest predictor in the model of treatment outcome. Our findings indicate that the critical breakpoints of some second-line drugs and PZA need to be reconsidered in order to better indicate MDR-TB treatment outcome.