Standardized Treatment of Active Tuberculosis in Patients with Previous Treatment and/or with Mono-resistance to Isoniazid: A Systematic Review and Meta-analysis

Background

A standardized regimen recommended by the World Health Organization for retreatment of active tuberculosis (TB) is widely used, but treatment outcomes are suspected to be poor. We conducted a systematic review of published evidence of treatment of patients with a history of previous treatment or documented isoniazid mono-resistance.

Methods and Findings

PubMed, EMBASE, and the Cochrane Central database for clinical trials were searched for randomized trials in previously treated patients and/or those with with mono-resistance to isoniazid, published in English, French, or Spanish between 1965 and June 2008. The first two sources were also searched for cohort studies evaluating specifically the current retreatment regimen. In studies selected for inclusion, rifampin-containing regimens were used to treat patients with bacteriologically confirmed pulmonary TB, in whom bacteriologically confirmed failure and/or relapse had been reported. Pooled cumulative incidences and 95% CIs of treatment outcomes were computed with random effects meta-analyses and negative binomial regression. No randomized trials of the currently recommended retreatment regimen were identified. Only six cohort studies were identified, in which failure rates were 18%–44% in those with isoniazid resistance. In nine trials, using very different regimens in previously treated patients with mono-resistance to isoniazid, the combined failure and relapse rates ranged from 0% to over 75%. From pooled analysis of 33 trials in 1,907 patients with mono-resistance to isoniazid, lower failure, relapse, and acquired drug resistance rates were associated with longer duration of rifampin, use of streptomycin, daily therapy initially, and treatment with a greater number of effective drugs.

Conclusions

There are few published studies to support use of the current standardized retreatment regimen. Randomized trials of treatment of persons with isoniazid mono-resistance and/or a history of previous TB treatment are urgently needed. Please see later in the article for the Editors'' Summary     

Month 2 Culture Status and Treatment Duration as Predictors of Recurrence in Pulmonary Tuberculosis: Model Validation and Update

Background

New regimens capable of shortening tuberculosis treatment without increasing the risk of recurrence are urgently needed. A 2013 meta-regression analysis, using data from trials published from 1973 to 1997 involving 7793 patients, identified 2-month sputum culture status and treatment duration as independent predictors of recurrence. The resulting model predicted that if a new 4-month regimen reduced the proportion of patients positive at month 2 to 1%, it would reduce to 10% the risk of a relapse rate >10% in a trial with 680 subjects per arm. The 1% target was far lower than anticipated.

Methods

Data from the 8 arms of 3 recent unsuccessful phase 3 treatment-shortening trials of fluoroquinolone-substituted regimens (REMox, OFLOTUB, and RIFAQUIN) were used to assess and refine the accuracy of the 2013 meta-regression model. The updated model was then tested using data from a treatment shortening trial reported in 2009 by Johnson et al.

Findings

The proportions of patients with recurrence as predicted by the 2013 model were highly correlated with observed proportions as reported in the literature (R2 = 0.86). Using the previously proposed threshold of 10% recurrences as the maximum likely considered acceptable by tuberculosis control programs, the original model correctly identified all 4 six-month regimens as satisfactory, and 3 of 4 four-month regimens as unsatisfactory (sensitivity = 100%, specificity = 75%, PPV = 80%, and NPV = 100%). A revision of the regression model based on the full dataset of 66 regimens and 11181 patients resulted in only minimal changes to its predictions. A test of the revised model using data from the treatment shortening trial of Johnson et al found the reported relapse rates in both arms to be consistent with predictions.

Interpretation

Meta-regression modeling of recurrence based on month 2 culture status and regimen duration can inform the design of future phase 3 tuberculosis clinical trials.     

Survey of pulmonary tuberculosis in south and west Wales (1976-8).

In routine clinical practice 20% of patients with pulmonary tuberculosis were treated with the regimen recommended by the British Thoracic Association after the British trial of short-course chemotherapy. Despite the use of several regimens that could be considered inadequate, no patients from the survey within south and west Wales appears to have relapsed yet. Deaths from pulmonary tuberculosis continue at the same rate as 10 years ago. Patient default remains a difficult problem even with modern, less toxic, short-course regimens.     

Zinc supplementation for prevention and management of recurrent aphthous stomatitis: a systematic review

BackgroundRecurrent aphthous stomatitis (RAS) is a very common oral ulcerative disease with no definitive cure. Growing evidence suggests a significant association between zinc deficiency and RAS.ObjectivesTo assess the efficacy of systemic zinc supplementations in the prevention and management of RAS.MethodsFive databases were searched for all English and Chinese studies published up to November 2020. All clinical trials that assessed the efficacy of zinc supplementations in the management and/or prevention of RAS were included.ResultsSeven clinical trials comprising 482 RAS patients (250 in zinc group) fulfilled the inclusion criteria. The follow-up period ranged from three months to one year. Five studies showed significantly better efficacy of zinc in reducing the recurrence rates of RAS, whereas two studies did not report any significant differences compared to the controls. Four studies reported on signs/symptoms of RAS, three of which showed superior outcomes in favour of zinc, while one study reported comparable results.ConclusionZinc supplementation seems to be efficacious in the management and prevention of RAS. However, further clinical trials with standardized methodologies and adequate follow-up periods are required to confirm the efficacy of zinc supplementations.     

Nine- to Twelve-Month Anti-Tuberculosis Treatment Is Associated with a Lower Recurrence Rate than 6–9-Month Treatment in Human Immunodeficiency Virus-Infected Patients: A Retrospective Population-Based Cohort Study in Taiwan

Background

Human immunodeficiency virus (HIV)-infected patients are at an increased risk of tuberculosis (TB) and its recurrence following completion of anti-TB treatment. We investigated whether extending anti-TB treatment to 9 months or longer reduces TB recurrence.

Methods

HIV-infected patients who were diagnosed with pulmonary TB between 1997 and 2009 and who received anti-TB treatment for a duration between 5.5 and 12.5 months were identified from the National Health Insurance Research Database in Taiwan. Those who received any non-fluoroquinolone second-line anti-TB drug for >28 days were excluded. Factors associated with TB recurrence within 2 years after completion of anti-TB treatment were explored using Cox regression analysis. Sensitivity analysis was performed for a subpopulation fulfilling strict diagnostic criteria for HIV infection.

Results

TB recurrence was observed in 18 (3.5%) of 508 HIV-infected patients. The recurrence rate declined from 5.4% to 1.0% after the implementation of directly observed therapy, short course (DOTS) in 2006 (p = 0.014). The recurrence rate was 5.9%, 5.2%, and 1.6% in patients who received anti-TB treatment for <195, 195–270, and >270 days, respectively (p = 0.066). Cox regression analysis revealed that TB diagnosed in the DOTS era (hazard ratio [HR]: 0.18 [0.04–0.77]) and anti-TB treatment for >270 days (HR: 0.24 [0.06–0.89]) were associated with a reduced risk of TB recurrence. Sensitivity analysis of 449 selected patients revealed that anti-TB treatment for >270 days was a significant factor.

Conclusion

In Taiwan, the 2-year TB recurrence rate in HIV-infected patients declined after implementation of DOTS. The risk of TB recurrence in HIV-infected patients can be further reduced by extending anti-TB treatment to 9–12.5 months.     

Statin use in the secondary prevention of coronary heart disease in primary care: cohort study and comparison of inclusion and outcome with patients in randomised trials

Objective To compare the social and demographic profiles of patients who receive statin treatment after myocardial infarction and patients included in randomised trials. To estimate the effect of statin use in community based patients on subsequent all cause mortality and cardiovascular recurrence, contrasting effects with trial patients.Design Observational cohort study using a record linkage database.Setting Tayside, Scotland (population size and characteristics: about 400 000, mixed urban and rural).Subjects 4892 patients were discharged from hospital after their first myocardial infarction between January 1993 and December 2001. 2463 (50.3%) were taking statins during an average follow-up of 3.7 years (3.1% in 1993 and 62.9% in 2001).Main outcome measures All cause mortality and recurrence of cardiovascular events.Results 319 deaths occurred in the statin treated group (age adjusted rate 4.1 per 100 person years, 95% confidence interval 3.2 to 4.9), and 1200 in the statin untreated group (12.7 per 100 person years, 11.1 to 14.3). More older people and women were represented in the population of patients treated with statins than among those recruited into clinical trials (mean age 67.8 v 59.8; women 39.6% v 16.9%, respectively). The effects of statins in routine clinical practice were consistent with, and similar to, those reported in clinical trials (adjusted hazard ratio for all cause mortality 0.69, 95% confidence interval 0.59 to 0.80; adjusted hazard ratio for cardiovascular recurrence 0.82, 0.71 to 0.95).Conclusions The community effectiveness of statins in those groups that were not well represented in clinical trials was similar to the efficacy of statins in these trials.     

Halo-vest辅助下前路手术治疗严重颈椎结核伴后凸畸形

目的：探讨使用halo-vest支具牵引复位并通过前路手术治疗严重颈椎结核并后凸畸形的方法和疗效。方法：通过对2004年10月至2010年9月在我科住院治疗的14例严重颈椎结核并后凸畸形的患者进行回顾性研究。本组患者中男8例,女6例,术前颈椎后凸Cobb角24-42°,平均34°。术前使用四联抗结核药物治疗2-4周,通过Halo-vest支具牵引复位。纠正颈椎后凸畸形后,采用一期前路手术治疗。手术处理包括：结核病灶清除、自体髂骨植骨或钛网植入、颈前路钢板内固定。术后继续抗结核治疗12-24个月。结果：术后随访12-48个月,平均26个月。所有颈椎结核并后凸畸形的患者都能通过halo-vest支具牵引恢复基本的颈椎序列,并能很好地耐受手术。术后患者局部疼痛和全身结核中毒症状明显缓解,神经功能均较术前有所恢复,后凸畸形得到矫正。术后3-6个月植骨融合,无内固定及伤口并发症,无严重halo-vest支具相关并发症,无结核复发。结论：对于严重颈椎结核并后凸畸形的患者,术前通过halo-vest支具牵引复位,可矫正畸形,恢复颈椎正常生理序列,为后期手术治疗创造条件并降低术中复位可能引起的脊髓损伤风险。Halo-vest辅助下的前路手术是治疗严重颈椎结核伴后凸畸形的有效手段。     

Selective use of abciximab in coronary stenting: overall outcomes can still be equivalent to those in the EPISTENT treatment group

BACKGROUND: The EPISTENT trial reported improved early outcomes with routine use of abciximab after coronary stenting. Increasing use of stents means that routine abciximab adds significantly to costs of percutaneous coronary intervention (PCI). This paper reports the results of a protocol encouraging restriction of abciximab therapy to high-risk patients only. METHODS: Data were collected prospectively over a 34-month period for patients undergoing PCI with stenting. In addition to those who fulfilled criteria for inclusion in the EPISTENT trial, patients treated in the setting of acute myocardial infarction (AMI) were studied. Demographic data, procedural details and early clinical outcomes were recorded. RESULTS: Of 808 patients studied, 601 fulfilled EPISTENT inclusion criteria and comprised 367 patients (45%) treated for stable angina and 234 (30%) treated for unstable or post-infarct angina. The additional 207 patients (25%) were treated during AMI. The 808 patients received a total of 981 stents. Abciximab was given in only 88 cases (10.9%). Major adverse clinical events occurred in 39 patients (4.8%). CONCLUSION: Selective use of abciximab for patients undergoing coronary stenting can be associated with outcomes equivalent to those reported for routine use, but with significant cost savings.     

Parenteral dexamethasone for acute severe migraine headache: meta-analysis of randomised controlled trials for preventing recurrence

Objective To examine the effectiveness of parenteral corticosteroids for the relief of acute severe migraine headache and prevention of recurrent headaches.Design Meta-analysis.Data sources Electronic databases (Cochrane Central Register of Controlled Trials, Medline, Embase, LILACS, and CINAHL), conference proceedings, clinical practice guidelines, contacts with industry, and correspondence with authors.Selection criteria Randomised controlled trials in which corticosteroids (alone or combined with standard abortive therapy) were compared with placebo or any other standard treatment for acute migraine in adults.Review methods Two reviewers independently assessed relevance, inclusion, and study quality. Weighted mean differences and relative risks were calculated and are reported with 95% confidence intervals.Results From 666 potentially relevant abstracts, seven studies met the inclusion criteria. All included trials used standard abortive therapy and subsequently compared single dose parenteral dexamethasone with placebo, examining pain relief and recurrence of headache within 72 hours. Dexamethasone and placebo provided similar acute pain reduction (weighted mean difference 0.37, 95% confidence interval −0.20 to 0.94). Dexamethasone was, however, more effective than placebo in reducing recurrence rates (relative risk 0.74, 95% confidence interval 0.60 to 0.90). Side effect profiles between dexamethasone and placebo groups were similar.Conclusion When added to standard abortive therapy for migraine headache, single dose parenteral dexamethasone is associated with a 26% relative reduction in headache recurrence (number needed to treat=9) within 72 hours.     

The effects of clinical practice guidelines on patient outcomes in primary care: a systematic review

OBJECTIVE: To assess the evidence for the effectiveness of clinical practice guidelines (CPGs) in improving patient outcomes in primary care. DATA SOURCES: A search of the MEDLINE, HEALTHPLAN, CINAHL and FAMLI databases was conducted to identify studies published between Jan. 1, 1980, and Dec. 31, 1995, concerning the use of guidelines in primary medical care. The keywords used in the search were "clinical guidelines," "primary care," "clinical care," "intervention," "randomized controlled trial" and "effectiveness." STUDY SELECTION: Studies of the use of CPGs were selected if they involved a randomized experimental or quasi-experimental method, concerned primary care, were related to clinical care and examined patient outcomes. Of 91 trials of CPGs identified through the search, 13 met the criteria for inclusion in the critical appraisal. DATA EXTRACTION: The following data were extracted, when possible, from the 13 trials: country and setting, number of physicians, number of patients (and the proportion followed to completion), length of follow-up, study method (including random assignment method), type of intervention, medical condition treated and effect on patient outcomes (including clinical and statistical significance, with confidence intervals). DATA SYNTHESIS: The most common conditions studied were hypertension (7 studies), asthma (2 studies) and cigarette smoking (2 studies). Four of the studies followed nationally developed guidelines, and 9 used locally developed guidelines. Six studies involved computerized or automated reminder systems, whereas the others relied on small-group workshops and education sessions. Only 5 of the 13 trials (38%) produced statistically significant results. CONCLUSION: There is very little evidence that the use of CPGs improves patient outcomes in primary medical care, but most studies published to date have used older guidelines and methods, which may have been insensitive to small changes in outcomes. Research is needed to determine whether the newer, evidence-based CPGs have an effect on patient outcomes.     

Systematic review of randomised controlled trials of strategies to promote adherence to tuberculosis treatment.

OBJECTIVE: To determine the effectiveness of strategies to promote adherence to treatment for tuberculosis. IDENTIFICATION: Searches in Medline (1966 to August 1996), the Cochrane trials register (up to October 1996), and LILACS (Literatura Latinoamericana y del Caribe en Ciencias de la Salud) (1982 to September 1996); screening of references in articles on compliance and adherence; contact with experts in research on tuberculosis and adherence. INCLUSION CRITERIA: Randomised or pseudorandomised controlled trials of interventions to promote adherence with curative or preventive treatment for tuberculosis, with at least one measure of adherence. MAIN OUTCOME MEASURE: Relative risks and 95% confidence intervals for estimates of effect for categorical outcomes. RESULTS: Five trials met the inclusion criteria. The relative risk for tested reminder cards sent to patients who defaulted on treatment was 1.2 (95% confidence interval 1.1 to 1.4), for help given to patients by lay health workers 1.4 (1.1 to 1.8), for monetary incentives offered to patients 1.6 (1.3 to 2.0), for health education 1.2 (1.1 to 1.4), for a combination of a patient incentive and health education 2.4 (1.5 to 3.7) or 1.1 (1.0 to 1.2), and for intensive supervision of staff in tuberculosis clinics 1.2 (1.1 to 1.3). There were no completed trials of directly observed treatment. All of the interventions tested improved adherence. On current evidence it is unclear whether health education by itself leads to better adherence to treatment. CONCLUSIONS: Reliable evidence is available to show some specific strategies improve adherence to tuberculosis treatment, and these should be adopted in health systems, depending on their appropriateness to practice circumstances. Further innovations require testing to help find specific approaches that will be useful in low income countries. Randomised controlled trials evaluating the independent effects of directly observed treatment are awaited.     

Progress in clinical trials for coronary arterial restenosis using beta radiation sources

Vascular brachytherapy has yet taken the leap into progression from emerging technology to standard of care dependent on the outcome of clinical trials. Data collected from early pilot trials and on-going clinical trials indicate that such a progression is achievable. Three-year follow-up data from patients treated with intracoronary radiation for the prevention of restenosis are now available. Data from larger trials are being assessed using angiographic and intravascular ultrasound analysis. The beta radiation studies are demonstrating different levels of efficacy, raising new issues regarding dosimetry and potential complications. Past trials have examined the use of vascular brachytherapy for recurrence prevention of restenosis in patients with in-stent restenosis. New data related to the use of liquid-filled balloon systems and radioactive stent are also being collected. This article updates the current status of clinical trials in vascular brachytherapy utilizing beta emitters, highlighting preliminary results and assessing their implications for the development of this field.     

Has the DOTS Strategy Improved Case Finding or Treatment Success? An Empirical Assessment

Background

Nearly fifteen years after the start of WHO''s DOTS strategy, tuberculosis remains a major global health problem. Given the lack of empirical evidence that DOTS reduces tuberculosis burden, considerable debate has arisen about its place in the future of global tuberculosis control efforts. An independent evaluation of DOTS, one of the most widely-implemented and longest-running interventions in global health, is a prerequisite for meaningful improvements to tuberculosis control efforts, including WHO''s new Stop TB Strategy. We investigate the impact of the expansion of the DOTS strategy on tuberculosis case finding and treatment success, using only empirical data.

Methods and Findings

We study the effect of DOTS using time-series cross-sectional methods. We first estimate the impact of DOTS expansion on case detection, using reported case notification data and controlling for other determinants of change in notifications, including HIV prevalence, GDP, and country-specific effects. We then estimate the effect of DOTS expansion on treatment success. DOTS programme variables had no statistically significant impact on case detection in a wide range of models and specifications. DOTS population coverage had a significant effect on overall treatment success rates, such that countries with full DOTS coverage benefit from at least an 18% increase in treatment success (95% CI: 5–31%).

Conclusions

The DOTS technical package improved overall treatment success. By contrast, DOTS expansion had no effect on case detection. This finding is less optimistic than previous analyses. Better epidemiological and programme data would facilitate future monitoring and evaluation efforts.     

Characteristics and programme-defined treatment outcomes among childhood tuberculosis (TB) patients under the national TB programme in Delhi

Background

Childhood tuberculosis (TB) patients under India''s Revised National TB Control Programme (RNTCP) are managed using diagnostic algorithms and directly observed treatment with intermittent thrice-weekly short-course treatment regimens for 6–8 months. The assignment into pre-treatment weight bands leads to drug doses (milligram per kilogram) that are lower than current World Health Organization (WHO) guidelines for some patients.

Objectives

The main aim of our study was to describe the baseline characteristics and treatment outcomes reported under RNTCP for registered childhood (age <15 years) TB patients in Delhi. Additionally, we compared the reported programmatic treatment completion rates between children treated as per WHO recommended anti-TB drug doses with those children treated with anti-TB drug doses below that recommended in WHO guidelines.

Methods

For this cross-sectional retrospective study, we reviewed programme records of all 1089 TB patients aged <15 years registered for TB treatment from January to June, 2008 in 6 randomly selected districts of Delhi. WHO disease classification and treatment outcome definitions are used by RNTCP, and these were extracted as reported in programme records.

Results and Conclusions

Among 1074 patients with records available, 651 (61%) were females, 122 (11%) were <5 years of age, 1000 (93%) were new cases, and 680 (63%) had extra-pulmonary TB (EP-TB)—most commonly peripheral lymph node disease [310 (46%)]. Among 394 pulmonary TB (PTB) cases, 165 (42%) were sputum smear-positive. The overall reported treatment completion rate was 95%. Similar reported treatment completion rates were found in all subgroups assessed, including those patients whose drug dosages were lower than that currently recommended by WHO. Further studies are needed to assess the reasons for the low proportion of under-5 years of age TB case notifications, address challenges in reaching all childhood TB patients by RNTCP, the accuracy of diagnosis, and the clinical validity of reported programme defined treatment completion.     

A novel approach to reducing disparities in health outcomes by enhancing interpretation of cancer clinical trials for underrepresented patient groups

There has been a growing realization, based on emerging evidence from the point of care, that real-world outcomes of patients with cancer are often inferior to those reported in conventional clinical trials. This phenomenon can be attributed in part to deficits in external validity that are present in many studies. Several factors contribute to external validity deficits, including: narrow eligibility criteria; differences between protocol-specified procedures and routine care; and inadequate access to clinical trial participation among underrepresented and socioeconomically disadvantaged groups. As a result, the current body of clinical evidence derived from conventional clinical trials can be inadequate to inform patient-specific treatment decisions at the point of care. Furthermore, lack of practical guidance on how to evaluate the impact of external validity deficits can impede both the design of more generalizable clinical trials and efforts to personalize treatment decisions for individual patients. In this methodological review, we suggest an approach to aid clinicians in such evaluations, providing visual and quantitative methods for assessing the magnitude of, and adjusting for, the impact of external validity deficits in conventional clinical trials. Our methods and visualizations have broad applicability across important areas of real-world medical decision-making and research, providing opportunities to design clinical studies that are more reflective of the diverse needs of patients with cancer, including those excluded from traditional clinical trials due to narrow eligibility criteria, socioeconomic disadvantages, and other systemic barriers to equitable access to healthcare resources.     

Primaquine radical cure of Plasmodium vivax: a critical review of the literature

ABSTRACT: BACKGROUND: Primaquine has been the only widely available hypnozoitocidal anti-malarial drug for half a century. Despite this its clinical efficacy is poorly characterized resulting in a lack of consensus over the optimal regimen for the radical cure of Plasmodium vivax. METHODS: Published studies since 1950 of the use of primaquine regimens for preventing P. vivax relapse were reviewed. Data were extracted systematically from available papers. Primaquine regimens were categorized according to the total dose administered: very low ([less than or equal to]2.5 mg/kg), low (>2.5 mg/kg- < 5.0 mg/kg) and high ([greater than or equal to] 5.0 mg/kg). The risk of recurrent infection were summarized across geographical regions and the odds ratios between treatment regimens calculated after stratifying by total treatment dose and duration of study follow up. RESULTS: Data could be retrieved from 87 clinical trials presenting data in 59,735 patients enrolled into 156 treatment arms, conducted in 20 countries. There was marked heterogeneity in study design, particularly primaquine dosing and duration of follow up. The median rate of recurrence following very low dose of primaquine (n = 44) was 25% (range 0-90%) at 4-6 months, compared to 6.7% (range 0-59%) following low dose primaquine (n = 82). High dose primaquine regimens were assessed in 28 treatment arms, and were associated with a median recurrence rate of 0% (Range: 0-15%) at one month. In 18 studies with control arms, the effectiveness of a very low dose primaquine regimen was no different from patients who did not receive primaquine (OR = 0.60, 95%CI 0.33-1.09, p = 0.09), whereas for the low dose regimens a significant difference was reported in 50% (6/12) of studies (overall OR = 0.14, 95%CI: 0.06-0.35, p < 0.001). Two studies enrolling 171 patients demonstrated high effectiveness of high dose primaquine compared to a control arm (OR = 0.03 (95%CI: 0.01- 0.13); p < 0.0001). CONCLUSIONS: Low dose regimens retain adequate efficacy in some areas, but this is not uniform. The efficacy and safety of pragmatic high dose primaquine regimens needs to be assessed in a range of endemic and geographical locations. Such studies will require a prolonged period of follow up and comparison with control arms to account for confounding factors.     

Anti-CD37 targeted immunotherapy of B-Cell malignancies

CD37 is a member of tetra-spanning superfamily (characterized by their four transmembrane domains). It is one of the specific proteins for normal and malignant mature B cells. Anti CD37 monoclonal antibodies are reported to improve the overall survival in CLL. These therapeutics will increase the efficacy and reduce the toxicity in patients with both newly diagnosed and relapsed and refractory disease. Recent clinical trials have shown promising outcomes for these agents, administered both as monotherapy and in combination with standard chemotherapeutics. Long-term follow-up of combination regimens has even raised the question of whether the patients with CLL could be treated with intensive chemo-immunotherapy. In the present study, CD37 is introduced as an appealing target to treat B cell malignancies. The anti-CD37 antibodies as one of the most successful therapeutics against CD37 are introduced and the clinical outcomes of their exploitation are explained.