Tuberculosis (TB) control is considered primarily a public health concern, and private sector TB treatment has attracted less attention. Thus, the size and characteristics of private sector TB drug ...sales remain largely unknown.
We used IMS Health data to analyze private TB drug consumption in 10 high burden countries (HBCs), after first mapping how well IMS data coverage overlapped with private markets. We defined private markets as any channels not used or influenced by national TB programs. Private markets in four countries--Pakistan, the Philippines, Indonesia and India--had the largest relative sales volumes; annually, they sold enough first line TB drugs to provide 65-117% of the respective countries' estimated annual incident cases with a standard 6-8 month regimen. First line drug volumes in five countries were predominantly fixed dose combinations (FDCs), but predominantly loose drugs in the other five. Across 10 countries, these drugs were available in 37 (loose drug) plus 74 (FDCs) distinct strengths. There were 54 distinct, significant first line manufacturers (range 2-11 per country), and most companies sold TB drugs in only a single study country. FDC markets were, however, more concentrated, with 4 companies capturing 69% of FDC volume across the ten countries. Among second line drugs, fluoroquinolones were widely available, with significant volumes used for TB in India, Pakistan and Indonesia. However, certain WHO-recommended drugs were not available and in general there were insufficient drug volumes to cover the majority of the expected burden of multidrug-resistant TB (MDR-TB).
Private TB drug markets in several HBCs are substantial, stable, and complicated. This calls for appropriate policy and market responses, including expansion of Public-Private Mix (PPM) programs, greater reach, flexibility and appeal of public programs, regulatory and quality enforcement, and expansion of public MDR-TB treatment programs.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Summary Background Pyrazinamide and fluoroquinolones are essential antituberculosis drugs in new rifampicin-sparing regimens. However, little information about the extent of resistance to these drugs ...at the population level is available. Methods In a molecular epidemiology analysis, we used population-based surveys from Azerbaijan, Bangladesh, Belarus, Pakistan, and South Africa to investigate resistance to pyrazinamide and fluoroquinolones among patients with tuberculosis. Resistance to pyrazinamide was assessed by gene sequencing with the detection of resistance-conferring mutations in the pncA gene, and susceptibility testing to fluoroquinolones was conducted using the MGIT system. Findings Pyrazinamide resistance was assessed in 4972 patients. Levels of resistance varied substantially in the surveyed settings (3·0–42·1%). In all settings, pyrazinamide resistance was significantly associated with rifampicin resistance. Among 5015 patients who underwent susceptibility testing to fluoroquinolones, proportions of resistance ranged from 1·0–16·6% for ofloxacin, to 0·5–12·4% for levofloxacin, and 0·9–14·6% for moxifloxacin when tested at 0·5 μg/mL. High levels of ofloxacin resistance were detected in Pakistan. Resistance to moxifloxacin and gatifloxacin when tested at 2 μg/mL was low in all countries. Interpretation Although pyrazinamide resistance was significantly associated with rifampicin resistance, this drug may still be effective in 19–63% of patients with rifampicin-resistant tuberculosis. Even though the high level of resistance to ofloxacin found in Pakistan is worrisome because it might be the expression of extensive and unregulated use of fluoroquinolones in some parts of Asia, the negligible levels of resistance to fourth-generation fluoroquinolones documented in all survey sites is an encouraging finding. Rational use of this class of antibiotics should therefore be ensured to preserve its effectiveness. Funding Bill & Melinda Gates Foundation, United States Agency for International Development, Global Alliance for Tuberculosis Drug Development.
The World Health Organization recommends the screening of all people living with HIV for tuberculosis (TB) disease, followed by TB treatment, or isoniazid preventive therapy (IPT) when TB is ...excluded. However, the difficulty of reliably excluding TB disease has severely limited TB screening and IPT uptake in resource-limited settings. We conducted an individual participant data meta-analysis of primary studies, aiming to identify a sensitive TB screening rule.
We identified 12 studies that had systematically collected sputum specimens regardless of signs or symptoms, at least one mycobacterial culture, clinical symptoms, and HIV and TB disease status. Bivariate random-effects meta-analysis and the hierarchical summary relative operating characteristic curves were used to evaluate the screening performance of all combinations of variables of interest. TB disease was diagnosed in 557 (5.8%) of 9,626 people living with HIV. The primary analysis included 8,148 people living with HIV who could be evaluated on five symptoms from nine of the 12 studies. The median age was 34 years. The best performing rule was the presence of any one of: current cough (any duration), fever, night sweats, or weight loss. The overall sensitivity of this rule was 78.9% (95% confidence interval CI 58.3%-90.9%) and specificity was 49.6% (95% CI 29.2%-70.1%). Its sensitivity increased to 90.1% (95% CI 76.3%-96.2%) among participants selected from clinical settings and to 88.0% (95% CI 76.1%-94.4%) among those who were not previously screened for TB. Negative predictive value was 97.7% (95% CI 97.4%-98.0%) and 90.0% (95% CI 88.6%-91.3%) at 5% and 20% prevalence of TB among people living with HIV, respectively. Abnormal chest radiographic findings increased the sensitivity of the rule by 11.7% (90.6% versus 78.9%) with a reduction of specificity by 10.7% (49.6% versus 38.9%).
Absence of all of current cough, fever, night sweats, and weight loss can identify a subset of people living with HIV who have a very low probability of having TB disease. A simplified screening rule using any one of these symptoms can be used in resource-constrained settings to identify people living with HIV in need of further diagnostic assessment for TB. Use of this algorithm should result in earlier TB diagnosis and treatment, and should allow for substantial scale-up of IPT.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Which New Diagnostics for Tuberculosis, and When? Cobelens, Frank; van den Hof, Susan; Pai, Madhukar ...
The Journal of infectious diseases,
05/2012, Letnik:
205, Številka:
suppl_2
Journal Article
Recenzirano
Odprti dostop
Recently, new diagnostic tools for tuberculosis detection and resistance testing have become available. The World Health Organization endorses new tuberculosis diagnostics by using the Grading of ...Recommendations Assessment, Development, and Evaluation (GRADE) process. This endorsement process takes place when limited evidence beyond test accuracy is available. There is a need to provide guidance to tuberculosis programs about which new diagnostics to scale up and how best to position them in diagnostic algorithms. To speed adoption of new diagnostics for tuberculosis, the policy recommendation process should be revised to consist of 2 steps: technical recommendation and programmatic recommendation. Technical recommendation would follow the GRADE process and be based on accuracy with limited cost and feasibility data, while programmatic recommendation would include patient-important outcomes, cost-effectiveness when implemented under routine conditions, and factors critical to successful scale-up. The evidence for both steps should be systematically collected, but each requires different study designs.
Use of antiretroviral therapy (ART) during treatment of drug susceptible tuberculosis (TB) improves survival. However, data from HIV infected individuals with drug resistant TB are lacking. Second ...line TB drugs when combined with ART may increase drug interactions and lead to higher rates of toxicity and greater noncompliance. This systematic review sought to determine the benefit of ART in the setting of second line drug therapy for drug resistant TB.
We included individual patient data from studies that evaluated treatment of drug-resistant tuberculosis in HIV-1 infected individuals published between January 1980 and December of 2009. We evaluated the effect of ART on treatment outcomes, time to smear and culture conversion, and adverse events.
Ten observational studies, including data from 217 subjects, were analyzed. Patients using ART during TB treatment had increased likelihood of cure (hazard ratio (HR) 3.4, 95% CI 1.6-7.4) and decreased likelihood of death (HR 0.4, 95% CI 0.3-0.6) during treatment for drug resistant TB. These associations remained significant in patients with a CD4 less than 200 cells/mm(3) and less than 50 cells/mm(3), and when correcting for drug resistance pattern.
We identified only observational studies from which individual patient data could be drawn. Limitations in study design, and heterogeneity in a number of the outcomes of interest had the potential to introduce bias.
While there are insufficient data to determine if ART use increases adverse drug interactions when used with second line TB drugs, ART use during treatment of drug resistant TB appears to improve cure rates and decrease risk of death. All individuals with HIV appear to benefit from ART use during treatment for TB.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Efficient, economical screening for active tuberculosis in resource-poor environments is a challenge. Screening is particularly important when there is coinfection with human immunodeficiency virus ...(HIV) and therefore concomitant consideration of initiation of antiretroviral therapy and the risk of the immune reconstitution syndrome. In this study of 1748 patients in Cambodia, Thailand, and Vietnam who were infected with HIV, an assessment for the presence of one of three symptoms — cough, fever, or night sweats — for more than 21 days over the preceding 4 weeks was found to have 93% sensitivity and 36% specificity for the detection of active tuberculosis infection.
In this study of patients in Cambodia, Thailand, and Vietnam who were infected with HIV, an assessment for the presence of one of three symptoms — cough, fever, or night sweats — for more than 21 days over the preceding 4 weeks was found to have 93% sensitivity and 36% specificity for the detection of active tuberculosis infection.
Tuberculosis is a leading cause of death among adults who are infected with the human immunodeficiency virus (HIV).
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In some countries, death occurs in up to 50% of these patients during treatment for tuberculosis, usually within 2 months after tuberculosis has been diagnosed.
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Delayed diagnosis of tuberculosis is probably an important contributor to high mortality.
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Antiretroviral therapy can substantially reduce the risk of death,
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,
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but initiating this therapy in a patient with untreated tuberculosis can lead to the immune-reconstitution inflammatory syndrome.
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To reduce the risk of tuberculosis, the World Health Organization (WHO) recommends the use of isoniazid . . .
Summary New tuberculosis drug regimens are creating new priorities for drug susceptibility testing (DST) and surveillance. To minimise turnaround time, rapid DST will need to be prioritised, but ...developers of these assays will need better data about the molecular mechanisms of resistance. Efforts are underway to link mutations with drug resistance and to develop strain collections to enable assessment of new diagnostic assays. In resource-limited settings, DST might not be appropriate for all patients with tuberculosis. Surveillance data and modelling will help country stakeholders to design appropriate DST algorithms and to decide whether to change drug regimens. Finally, development of practical DST assays is needed so that, in countries where surveillance and modelling show that DST is advisable, these assays can be used to guide clinical decisions for individual patients. If combined judiciously during both development and implementation, new tuberculosis regimens and new DST assays have enormous potential to improve patient outcomes and reduce the burden of disease.
Although nontuberculous mycobacteria (NTM) are widely documented as a cause of illness among HIV-infected people in the developed world, studies describing the prevalence of NTM disease among ...HIV-infected people in most resource-limited settings are rare.
To evaluate the prevalence of mycobacterial disease in HIV-infected patients in Southeast Asia.
We enrolled people with HIV from three countries in Southeast Asia and collected pulmonary and extrapulmonary specimens to evaluate the prevalence of mycobacterial disease. We adapted American Thoracic Society/Infectious Disease Society of America guidelines to classify patients into NTM pulmonary disease, NTM pulmonary disease suspects, NTM disseminated disease, and no NTM categories.
In Cambodia, where solid media alone was used, NTM was rare. Of 1,060 patients enrolled in Thailand and Vietnam, where liquid culture was performed, 124 (12%) had tuberculosis and 218 (21%) had NTM. Of 218 patients with NTM, 66 (30%) were classified as NTM pulmonary disease suspects, 9 (4%) with NTM pulmonary disease, and 10 (5%) with NTM disseminated disease. The prevalence of NTM disease was 2% (19 of 1,060). Of 51 patients receiving antiretroviral therapy (ART), none had NTM disease compared with 19 (2%) of 1,009 not receiving ART.
Although people with HIV frequently have sputum cultures positive for NTM, few meet a strict case definition for NTM disease. Consistent with previous studies, ART was associated with lower odds of having NTM disease. Further studies of NTM in HIV-infected individuals in tuberculosis-endemic countries are needed to develop and validate case definitions.
Frank Cobelens and colleagues outline key research questions that need to be addressed to maximize the impact of programmatic management of drug-resistant tuberculosis.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Drug resistance in malaria and in tuberculosis (TB) are major global health problems. Although the terms multidrug-resistant TB and extensively drug-resistant TB are precisely defined, the term ...multidrug resistance is often loosely used when discussing malaria. Recent declines in the clinical effectiveness of antimalarial drugs, including artemisinin-based combination therapy, have prompted the need to revise the definitions of and/or to recategorize antimalarial drug resistance to include extensively drug-resistant malaria. Applying precise case definitions to different levels of drug resistance in malaria and TB is useful for individual patient care and for public health.
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DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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