Pooling sputum samples for Xpert® MTB/RIF and Xpert® Ultra testing for TB diagnosis

BACKGROUND

The use of molecular amplification as-says for TB diagnosis is limited by their costs and cartridge stocks. Pooling multiple samples to test them together is reported to have similar accuracy to individual testing and to save costs.

METHODS

Two surveys of individuals with presumptive TB were conducted to assess the performance of pooled testing using Xpert® MTB/RIF (MTB/RIF) and Xpert® Ultra (Ultra).

RESULTS

A total of 500 individuals were tested using MTB/RIF, with 72 (14.4%) being MTB-positive. The samples were tested in 125 pools, with 50 pools having ⩾1 MTB-positive and 75 only MTB-negative samples: 46/50 (92%, 95% CI 80.8-97.8) MTB-positive pools tested MTB-positive and 71/75 (94.7%, 95% CI 86.9-98.5) MTB-negative pools tested MTB-negative in the pooled test (agreement: 93.6%, κ = 0.867). Five hundred additional samples were tested using Ultra, with 60 (12%) being MTB-positive. Samples were tested in 125 pools, with 42 having ⩾1 MTB-positive and 83 only MTB-negative samples: 35/42 (83.6%, 95% CI 68.6-93.0) MTB-positive pools tested MTB-positive and 82/83 (98.8%, 95% CI 93.5-100.0) MTB-negative pools tested MTB-negative in the pooled test (agreement: 93.6%, κ = 0.851; P > 0.1 between individual and pooled testing). Pooled testing saved 35% (MTB/RIF) and 46% (Ultra) of cartridges.

CONCLUSIONS

Pooled and individual testing has a high level of agreement and improves testing efficiency.

Patient-cost survey for tuberculosis in the context of patient-pathway modelling

SETTING: Eight tuberculosis treatment sites in Cavite Province, the Philippines, including two sites specialising in management of multidrug-resistant tuberculosis (MDR-TB).OBJECTIVE: To evaluate costs incurred by TB patients and to determine the proportion of households that faced catastrophic costs, then to consider cost survey responses alongside results of detailed patient-pathway modelling.DESIGN: Clustered cross-sectional survey using a field testing version of the WHO TB patient-costing tool and protocol; face-to-face interviews with 194 patients conducted in May-August 2016. Costs included direct-medical, direct non-medical and indirect costs using the human capital approach. Patients were deemed to incur catastrophic expenditure if TB-related costs exceeded 20% of annual household income. Patient pathways were modelled following multiple health staff interviews.RESULTS: Estimated mean cost incurred by patients with drug-susceptible TB was US$321 vs. $2356 for MDR-TB patients. Catastrophic costs were suffered by 28% of drug-susceptible and 80% of MDR-TB patients, with lost income being the largest contributor. Patient-pathway modelling suggested most patients had under-reported health visits.CONCLUSION: Survey results indicate that patient costs are large for all patients in Cavite, particularly for MDR-TB patients. Patient-pathway modelling suggests these costs are an underestimate due to poor recollection of health visits, suggesting that the WHO instrument and protocol could be improved to better capture the diagnostic journey.

Contacts of underserved tuberculosis patients have higher odds of TB disease in North West England: a cohort study

OBJECTIVE

To investigate the association between patients' social risk factors and the risk of tuberculous infection and TB disease among their contacts in England.

DESIGN

This was a cohort study of all TB cases from North West England diagnosed between 27 March 2012 and 28 June 2016. The social risk factors of TB cases were evaluated to estimate their need for enhanced case management (ECM), from 0 (standard of care) to 3 (intensive social support).

RESULTS

A total of 2139 cases and their 10 019 contacts met the eligibility criteria. Being a contact of a patient with smear-positive TB with high ECM or being of Black Caribbean ethnicity was independently associated with greater odds of active TB disease (smear-positive vs. smear-negative, OR 5.3, 95%CI 3.2-8.7; ECM-3 vs. ECM-0, OR 2.2, 95%CI 1.01-5.0; Black Caribbean vs. White, OR 7.4, 95%CI 2.1-25). Being a contact of a patient with smear-positive TB or of Black Caribbean ethnicity was also independently associated with greater odds of tuberculous infection (smear-positive vs. smear-negative, OR 5.3, 95%CI 3.8-7.3; and Black Caribbean vs. White, OR 6.7, 95%CI 2.0-25).

CONCLUSIONS

The social complexity and ethnicity of patients were associated with tuberculous infection and TB disease in their contacts.

A systematic review of clinical outcomes on the WHO Category II retreatment regimen for tuberculosis

OBJECTIVE

To assess the clinical outcomes of patients prescribed the World Health Organization (WHO) Category II retreatment regimen for tuberculosis (TB).

DESIGN

A systematic review of the literature was performed by searching Medscape, Embase and Scopus databases for cohort studies and clinical trials reporting outcomes in adult patients on the Category II retreatment regimen.

RESULTS

The proportion of patients successfully completing the retreatment regimen varied from 27% to 92% in the 39 studies included in this review. In only 2/39 (5%) studies was the treatment success rate > 85%. There are very few data concerning outcomes in patients categorised as 'other', and outcomes in this subgroup are variable. Of the five studies reporting disaggregated outcomes in human immunodeficiency virus (HIV) positive people, four demonstrated worse outcomes than in HIV-negative people on the retreatment regimen. Only four studies reported disaggregated outcomes in patients with isoniazid (INH) resistance, and treatment success rates varied from 11% to 78%.

CONCLUSION

Clinical outcomes on the Category II retreatment regimen are poor across various populations. Improvements in management should consider the holistic treatment of comorbidity and comprehensive approaches to drug resistance in patients with recurrent TB, including a standardised approach for the management of INH resistance in patients who develop recurrent TB in settings without reliable access to comprehensive drug susceptibility testing.

Cost minimization analysis of line probe assay for detection of multidrug-resistant tuberculosis in Arkhangelsk region of Russian Federation

Background

The development of new diagnostic tools allows for faster detection of both tuberculosis (TB) and multidrug-resistant (MDR) TB and should lead to reduced transmission by earlier initiation of anti TB therapy. The research conducted in the Arkhangelsk region of the Russian Federation in 2012–14 included economic evaluation of Line Probe Assay (LPA) implementation in MDR-TB diagnostics compared to existing culture-based diagnostics of Löwenstein Jensen (LJ) and BacTAlert. Clinical superiority of LPA was demonstrated and results were reported elsewhere.

Study aim

The PROVE-IT Russia study aimed to report the outcomes of the cost minimization analysis.

Methods

Costs of LPA-based diagnostic algorithm (smear positive (SSm+) and for smear negative (SSm-) culture confirmed TB patients by Bactec MGIT or LJ were compared with conventional culture-based algorithm (LJ–for SSm- and SSm+ patients and BacTAlert–for SSm+ patients). Cost minimization analysis was conducted from the healthcare system, patient and societal perspectives and included the direct and indirect costs to the healthcare system (microscopy and drug susceptibility test (DST), hospitalization, medications obtained from electronic medical records) and non-hospital direct costs (patient’s travel cost, additional expenses associated with hospitalization, supplementary medicine and food) collected at the baseline and two subsequent interviews using the WHO-approved questionnaire.

Results

Over the period of treatment the LPA-based diagnostic corresponded to lesser direct and indirect costs comparing to the alternative algorithms. For SSm+ LPA-based diagnostics resulted in the costs 4.5 times less (808.21 US$) than LJ (3593.81 US$) and 2.5 times less than BacTAlert liquid culture (2009.61 US$). For SSm- LPA in combination with Bactec MGIT (1480.75 US$) vs LJ (1785.83 US$) showed the highest cost minimization compared to LJ (2566.09 US$). One-way sensitivity analyses of the key parameters and threshold analyses were conducted and demonstrated that the results were robust to variations in the cost of hospitalization, medications and length of stay.

Conclusion

From the perspective of Russian Federation healthcare system, TB diagnostic algorithms incorporating LPA method proved to be both more clinically effective and less expensive due to reduction in the number of hospital days to the correct MDR-TB diagnosis and treatment initiation. LPA diagnostics comparing conventional culture diagnostic algorithm MDR-TB was a cost minimizing strategy for both patients and healthcare system.

A qualitative evaluation of hospital versus community-based management of patients on injectable treatments for tuberculosis

BACKGROUND

Patients being treated for recurrent or multidrug-resistant tuberculosis (TB) require long courses of injectable anti-tuberculous agents. In order to maintain strong TB control programmes, it is vital that the experiences of people who receive long-term injectables for TB are well understood. To investigate the feasibility of a novel model of care delivery, a clinical trial (The TB-RROC Study) was conducted at two central hospitals in Malawi. Hospital-based care was compared to a community-based approach for patients on TB retreatment in which 'guardians' (patient-nominated lay people) were trained to deliver injections to patients at home. This study is the qualitative evaluation of the TB-RROC trial. It examines the experiences of people receiving injectables as part of TB treatment delivered in hospital and community-based settings.

METHODS

A qualitative evaluation of the TB-RROC intervention was conducted using phenomenographic methods. Trial participants were purposively sampled, and in-depth interviews were conducted with patients and guardians in both arms of the trial. Key informant interviews and observations in the wards and community were performed. Thematic content analysis was used to derive analytical themes.

RESULTS

Fourteen patients, 12 guardians and 9 key informants were interviewed. Three key themes relating to TB retreatment emerged: medical experiences (including symptoms, treatment, and HIV); the effects of the physical environment (conditions on the ward, disruption to daily routines and livelihoods); and trust (in other people, the community and in the health system). Experiences were affected by the nature of a person's prior role in their community and resulted in a range of emotional responses. Patients and guardians in the community benefited from better environment, social interactions and financial stability. Concerns were expressed about the potential for patients' health or relationships to be adversely affected in the community. These potential concerns were rarely realised.

CONCLUSIONS

Guardian administered intramuscular injections were safe and well received. Community-based care offered many advantages over hospital-based care for patients receiving long-term injectable treatment for TB and their families.

Comparing laboratory costs of smear/culture and Xpert® MTB/RIF-based tuberculosis diagnostic algorithms

SETTING

Cape Town, South Africa, where Xpert^® MTB/RIF was introduced as a screening test for all presumptive tuberculosis (TB) cases.

OBJECTIVE

To compare laboratory costs of smear/culture- and Xpert-based tuberculosis (TB) diagnostic algorithms in routine operational conditions.

METHODS

Economic costing was undertaken from a laboratory perspective, using an ingredients-based costing approach. Cost allocation was based on reviews of standard operating procedures and laboratory records, timing of test procedures, measurement of laboratory areas and manager interviews. We analysed laboratory test data to assess overall costs and cost per pulmonary TB and multidrug-resistant TB (MDR-TB) case diagnosed. Costs were expressed as 2013 Consumer Price Index-adjusted values.

RESULTS

Total TB diagnostic costs increased by 43%, from US$440 967 in the smear/culture-based algorithm (April-June 2011) to US$632 262 in the Xpert-based algorithm (April-June 2013). The cost per TB case diagnosed increased by 157%, from US$48.77 (n = 1601) to US$125.32 (n = 1281). The total cost per MDR-TB case diagnosed was similar, at US$190.14 and US$183.86, with 95 and 107 cases diagnosed in the respective algorithms.

CONCLUSION

The introduction of the Xpert-based algorithm resulted in substantial cost increases. This was not matched by the expected increase in TB diagnostic efficacy, calling into question the sustainability of this expensive new technology.

Outcomes from patients with presumed drug resistant tuberculosis in five reference centers in Brazil

Background

The implementation of rapid drug susceptibility testing (DST) is a current global priority for TB control. However, data are scarce on patient-relevant outcomes for presumptive diagnosis of drug-resistant tuberculosis (pDR-TB) evaluated under field conditions in high burden countries.

Methods

Observational study of pDR-TB patients referred by primary and secondary health units. TB reference centers addressing DR-TB in five cities in Brazil. Patients age 18 years and older were eligible if pDR-TB, culture positive results for Mycobacterium tuberculosis and, if no prior DST results from another laboratory were used by a physician to start anti-TB treatment. The outcome measures were median time from triage to initiating appropriate anti-TB treatment, empirical treatment and, the treatment outcomes.

Results

Between February,16th, 2011 and February, 15th, 2012, among 175 pDR TB cases, 110 (63.0%) confirmed TB cases with DST results were enrolled. Among study participants, 72 (65.5%) were male and 62 (56.4%) aged 26 to 45 years. At triage, empirical treatment was given to 106 (96.0%) subjects. Among those, 85 were treated with first line drugs and 21 with second line. Median time for DST results was 69.5 [interquartile - IQR: 35.7–111.0] days and, for initiating appropriate anti-TB treatment, the median time was 1.0 (IQR: 0–41.2) days. Among 95 patients that were followed-up during the first 6 month period, 24 (25.3%; IC: 17.5%–34.9%) changed or initiated the treatment after DST results: 16/29 MDRTB, 5/21 DR-TB and 3/45 DS-TB cases. Comparing the treatment outcome to DS-TB cases, MDRTB had higher proportions changing or initiating treatment after DST results (p = 0.01) and favorable outcomes (p = 0.07).

Conclusions

This study shows a high rate of empirical treatment and long delay for DST results. Strategies to speed up the detection and early treatment of drug resistant TB should be prioritized.

The 'Practical Approach to Lung Health' in sub-Saharan Africa: a systematic review

SETTING: There is a high burden of respiratory disease in sub-Saharan Africa. To address this problem, the World Health Organization launched the ‘Practical approach to Lung Health’ (PAL), i.e., locally applicable integrated syndromic algorithms, to improve primary care management of these diseases.

OBJECTIVE: To examine the evidence for the impact of PAL on the diagnosis and management of tuberculosis (TB) and other common respiratory problems in sub-Saharan Africa.

DESIGN: A systematic review of MEDLINE (1998–2015), EMBASE (1998–2015) and CINAHL (1998–2015) was conducted to find trials evaluating PAL implementation in sub-Saharan Africa.

RESULTS: Five studies were found, evaluating three PAL variations: PAL in South Africa (PALSA), PALSA with integrated human immunodeficiency virus treatment (PALSA PLUS) and PAL in Malawi using lay health workers (PALM/LHW). PALSA increased TB diagnosis (OR 1.72, 95%CI 1.04–2.85), as did PALSA PLUS (OR 1.25, 95%CI 1.01–1.55). Cure or completion rates in retreatment cases in PALSA and PALSA PLUS were significantly improved (OR 1.78, 95%CI 1.13–2.76). PALM/LHW, which examined TB treatment success, found no significant improvement (P = 0.578).

CONCLUSION: The limited research performed shows that PAL can be effective in TB diagnosis and partial treatment success; however, more evidence is needed to assess its effects on other respiratory diseases, especially in wider sub-Saharan Africa.

The impact of user fees on health services utilization and infectious disease diagnoses in Neno District, Malawi: a longitudinal, quasi-experimental study

Background

User fees have generally fallen out of favor across Africa, and they have been associated with reductions in access to healthcare. We examined the effects of the introduction and removal of user fees on outpatient attendances and new diagnoses of HIV, malaria, and tuberculosis in Neno District, Malawi where user fees were re-instated at three of 13 health centres in 2013 and subsequently removed at one of these in 2015.

Methods

We conducted two analyses. Firstly, an unadjusted comparison of outpatient visits and new diagnoses over three periods between July 2012 and October 2015: during the period with no user fees, at the re-introduction of user fees at four centres, and after the removal of user fees at one centre. Secondly, we estimated a linear model of the effect of user fees on the outcome of interest that controlled for unobserved health centre effects, monthly effects, and a linear time trend.

Results

The introduction of user fees was associated with a change in total attendances of −68 % [95 % CI: −89 %, −12 %], similar reductions were observed for new malaria and HIV diagnoses. The removal of user fees was associated with an increase in total attendances of 352 % [213 %, 554 %] with similar increases for malaria diagnoses. The results were not sensitive to control group or model specification.

Conclusions

User fees for outpatient healthcare services present a barrier to patients accessing healthcare and reduce detection of serious infectious diseases.

Electronic supplementary material

The online version of this article (doi:10.1186/s12913-016-1856-x) contains supplementary material, which is available to authorized users.

Impact and cost-effectiveness of current and future tuberculosis diagnostics: the contribution of modelling

The landscape of diagnostic testing for tuberculosis (TB) is changing rapidly, and stakeholders need urgent guidance on how to develop, deploy and optimize TB diagnostics in a way that maximizes impact and makes best use of available resources. When decisions must be made with only incomplete or preliminary data available, modelling is a useful tool for providing such guidance. Following a meeting of modelers and other key stakeholders organized by the TB Modelling and Analysis Consortium, we propose a conceptual framework for positioning models of TB diagnostics. We use that framework to describe modelling priorities in four key areas: Xpert^® MTB/RIF scale-up, target product profiles for novel assays, drug susceptibility testing to support new drug regimens, and the improvement of future TB diagnostic models. If we are to maximize the impact and cost-effectiveness of TB diagnostics, these modelling priorities should figure prominently as targets for future research.

Equitable tuberculosis care in the North West of England: analysis of tuberculosis cohort review data

BACKGROUND: In the United Kingdom, tuberculosis (TB) predominantly affects the most deprived populations, yet the extent to which deprivation affects TB care outcomes is unknown.

METHODS: Since 2011, the North West TB Cohort Audit collaboration has undertaken quarterly reviews of outcomes against consensus-defined care standard indicators for all individuals notified with TB. We investigated associations between adverse TB care outcomes and Index of Multiple Deprivation (IMD) 2010 scores measured at lower super output area of residence using logistic regression models.

RESULTS: Of 1831 individuals notified with TB between 2011 and 2014, 62% (1131/1831) came from the most deprived national quintile areas. In single variable analysis, greater deprivation was significantly associated with increased likelihood of the completion of a standardised risk assessment (OR 2.99, 95%CI 5.27–19.65) and offer of a human immunodeficiency virus test (OR 1.72, 95%CI 1.10–2.62). In multivariable analysis, there were no significant associations.

CONCLUSIONS: TB patients in the most deprived areas had similar care indicators across a range of standards to those of individuals living in the more affluent areas, suggesting that the delivery of TB care in the North West of England is equitable. The extent to which the cohort review process contributes to, and sustains, this standard of care deserves further study.

Comparing multidrug-resistant tuberculosis patient costs under molecular diagnostic algorithms in South Africa

SETTING

Ten primary health care facilities in Cape Town, South Africa, 2010-2013.

OBJECTIVE

A comparison of costs incurred by patients in GenoType MDRTBplus line-probe assay (LPA) and Xpert MTB/RIF-based diagnostic algorithms from symptom onset until treatment initiation for multidrug-resistant tuberculosis (MDR-TB).

METHODS

Eligible patients identified from laboratory and facility records were interviewed 3-6 months after treatment initiation and a cost questionnaire completed. Direct and indirect costs, individual and household income, loss of individual income and change in household income were recorded in local currency, adjusted to 2013 costs and converted to $US.

RESULTS

Median number of visits to initiation of MDR-TB treatment was reduced from 20 to 7 (P < 0.001) and median costs fell from US$68.1 to US$38.3 (P = 0.004) in the Xpert group. From symptom onset to being interviewed, the proportion of unemployed increased from 39% to 73% in the LPA group (P < 0.001) and from 53% to 89% in the Xpert group (P < 0.001). Median household income decreased by 16% in the LPA group and by 13% in the Xpert group.

CONCLUSION

The introduction of an Xpert-based algorithm brought relief by reducing the costs incurred by patients, but loss of employment and income persist. Patients require support to mitigate this impact.

Health professionals' experiences of tuberculosis cohort audit in the North West of England: a qualitative study

OBJECTIVES

Tuberculosis cohort audit (TBCA) was introduced across the North West (NW) of England in 2012 as an ongoing, multidisciplinary, systematic case review process, designed to improve clinical and public health practice. TBCA has not previously been introduced across such a large and socioeconomically diverse area in England, nor has it undergone formal, qualitative evaluation. This study explored health professionals' experiences of the process after 1515 cases had been reviewed.

DESIGN

Qualitative study using semistructured interviews. Respondents were purposively sampled from 3 groups involved in the NW TBCA: (1) TB nurse specialists, (2) consultant physicians and (3) public health practitioners. Data from the 26 respondents were triangulated with further interviews with key informants from the TBCA Steering Group and through observation of TBCA meetings.

ANALYSIS

Interview transcripts were analysed thematically using the framework approach.

RESULTS

Participants described the evolution of a valuable 'community of practice' where interprofessional exchange of experience and ideas has led to enhanced mutual respect between different roles and a shared sense of purpose. This multidisciplinary, regional approach to TB cohort audit has promoted local and regional team working, exchange of good practices and local initiatives to improve care. There is strong ownership of the process from public health professionals, nurses and clinicians; all groups want it to continue. TBCA is regarded as a tool for quality improvement that improves patient safety.

CONCLUSIONS

TBCA provides peer support and learning for management of a relatively rare, but important infectious disease through discussion in a no-blame atmosphere. It is seen as an effective quality improvement strategy which enhances TB care, control and patient safety. Continuing success will require increased engagement of consultant physicians and public health practitioners, a secure and ongoing funding stream and establishment of clear reporting mechanisms within the public health system.

CAHRD Consultation 2014: the 10-20 year Horizon Introduction and Overview - as circulated to Consultation participants

The overall aim of the 2014 Consultation is to bring together internal and external partners to help shape the strategic direction for CAHRD over the 10 to 20 year horizon. Our strategic thinking will be guided by our vision of a healthy future for low and middle income populations and our mission to transform health systems to improve the health of these populations. Partnership between northern and southern institutions is integral to this work and critical in the consultation process. The Consultation considers four selected areas of the current work of CAHRD: Lung Health, Maternal & Newborn Health, Neglected Tropical Diseases, and Health Systems. We aim to foster dialogue and learning between these and across contexts and disciplines. The major challenges that will need to be addressed over the next 10 to 20 years will be scoped and pathways to possible solutions proposed. The overall vision is a process of co-production of knowledge

Catastrophic care-seeking costs as an indicator for lung health

Costs incurred during care-seeking for chronic respiratory disease are a major problem with severe consequences for socio-economic status and health outcomes. Most of the published evidence to date relates to tuberculosis (TB) and there is a lack of information for the major non-communicable chronic respiratory diseases: asthma and chronic obstructive pulmonary disease (COPD). International policy is recognising the need to address this problem and measure progress towards eliminating catastrophic care-seeking costs (see the post-2015 TB strategy). Current tools for measuring, defining, and understanding the full consequences of catastrophic care-seeking costs are inadequate. We propose two areas of work which are urgently needed to prepare health systems and countries for the burden of chronic lung disease that will fall on poor populations in the coming 10-20 years: a) Rapid scale up of the number and scope of studies of patient costs associated with chronic non-communicable respiratory disease. b) Work towards deeper understanding and effective measurement of catastrophic care-seeking costs. This will produce a range of indicators, such as dissaving, which can more effectively inform health policy decision-making for lung health. These will also be useful for other health problems. We argue that reduction in care-seeking costs will be a key monitoring indicator for improvements in lung health in particular, and health in general, in the coming 10 to 20 years.

Patient costs during tuberculosis treatment in Bangladesh and Tanzania: the potential of shorter regimens

OBJECTIVE

To estimate the costs incurred by patients during the intensive and continuation phases of the current 6-month tuberculosis (TB) regimen in Bangladesh and Tanzania, and thus identify potential benefits to patients of a shorter, 4-month treatment regimen.

DESIGN

The validated Stop TB patient cost questionnaire was adapted and used in interviews with 190 patients in the continuation phase of treatment with current regimens.

RESULTS

In both countries, overall patient costs were lower during 2 months of the continuation phase (US$74 in Tanzania and US$56 in Bangladesh) than during the 2 months of the intensive phase of treatment (US$150 and US$111, respectively). However, continuation phase patient costs still represented 89% and 77% of the 2-month average national income in the respective countries. Direct travel costs in some settings were kept low by local delivery system features such as community treatment observation. Lost productivity and costs for supplementary foods remained significant.

CONCLUSIONS

Although it is not a straightforward exercise to determine the exact magnitude of likely savings, a shorter regimen would reduce out-of-pocket expenses incurred by patients in the most recent 2 months of the continuation phase and allow an earlier return to productive activities.

Performance of the Xpert® MTB/RIF assay in an active case-finding strategy: a pilot study from Tanzania

In this pilot study, we evaluated the Xpert® MTB/RIF assay in an active case-finding strategy, using two spot sputum samples collected within a 1-hour interval from household contacts of smear-positive TB index cases. Tuberculosis (TB) confirmed by culture served as the reference standard. Among 219 enrolled contacts, the yield of active TB was 2.3%. While the sensitivity of smear microscopy was 60% (95%CI 14.7-94.7), Xpert MTB/RIF achieved a sensitivity of 100% (95%CI 47.81-100.0). All culture-confirmed cases tested positive by Xpert MTB/RIF on the first submitted sample, suggesting that the evaluation of only one sample could be sufficient for TB diagnosis in this context.

The role of health economics research in implementation research for health systems strengthening

It has long been recognised that the health-related Millennium Development Goals cannot be achieved without strengthened health systems. This article presents the most recent World Health Organization framework for strengthening health systems and considers how health economics research can be used to measure achievements against each of the goals of the framework. Benefits to health systems strengthening of incorporating health economics tools into operational research are highlighted. Finally, health economic tools are placed within an impact assessment framework that facilitates the capture of health systems considerations in implementation research for innovations in tuberculosis diagnosis.

A systematic review of risk factors for death in adults during and after tuberculosis treatment

BACKGROUND

Despite effective anti-tuberculosis chemotherapy, case-fatality rates of up to 25% are described in both industrialised and resource-poor settings. An understanding of the factors predisposing to poor outcome may allow the development of adjunctive treatment strategies or closer clinical monitoring in high-risk individuals.

OBJECTIVES

To describe the definitions and timing of deaths due to tuberculosis (TB), and the reported range of risk factors for death.

METHODS

All electronically available studies investigating risk factors for death in TB patients from 1966 to 2010 were analysed. Included were peer-reviewed reports of cohort, case control or cross-sectional studies with the primary objective of determination of quantitative effect estimates of the relationship between risk factors and death in adults treated for TB. Many studies were limited by their retrospective design, reliance on data from registries and charts, and risk of reporting bias.

RESULTS

Most studies reported risk factors for all-cause mortality throughout anti-tuberculosis treatment. In the context of high TB incidence and human immunodeficiency virus (HIV) prevalence, risk factors for death are HIV positivity, advancing immunosuppression, smear-negative disease and malnutrition. In regions of low TB incidence and HIV prevalence, risk factors include non-infective comorbidities, sputum smear-positive disease and alcohol and substance misuse.

CONCLUSIONS

There remains a need for prospective clinical studies, particularly with a focus on deaths occurring during the first months of anti-tuberculosis treatment. Qualitative research should be used to further explore the relationship between sex and health-seeking behaviour, and to optimise delivery of health care to socially marginalised groups.

Beyond accuracy: creating a comprehensive evidence base for TB diagnostic tools

The need for a strong and comprehensive evidence base to support decision making with regard to the implementation of new and improved diagnostic tools and approaches has been highlighted by a number of stakeholders; these include members of the New Diagnostics Working Group (NDWG) and the Subgroup for Introducing New Approaches and Tools of the Stop TB Partnership. To compile such evidence in a systematic manner, we have developed an impact assessment framework (IAF) which links evidence on inputs to outcomes. The IAF comprises five interconnected layers: effectiveness analysis, equity analysis, health systems analysis, scale-up analysis and policy analysis. It can be used by new diagnostics developers and other interested research teams to collect as much policy-relevant data as possible prior to, during and after the demonstration phase of tool development. The evidence collated may be used by international and national policy makers to support adoption, implementation and scale-up decisions. The TREAT TB (Technology, Research, Education and Technical Assistance for TB) initiative uses the IAF in its operational research and field evaluations of new tools and approaches for TB diagnosis. It has also been incorporated into the NDWG's recent publication: 'Pathways to better diagnostics for tuberculosis: a blueprint for the development of TB diagnostics'. This article describes the IAF and the process of improving it and suggests next steps in overcoming the challenges in its implementation.

Simple measures are as effective as invasive techniques in the diagnosis of pulmonary tuberculosis in Malawi

SETTING

Detection of smear-positive pulmonary tuberculosis (PTB) cases is vital for tuberculosis (TB) control. Methods to augment sputum collection are available, but their additional benefit is uncertain in resource-limited settings.

OBJECTIVE

To compare the diagnostic yields using five methods to obtain sputum from adults diagnosed with smear-negative PTB in Malawi.

DESIGN

Self-expectorated sputum was collected under supervision for microscopy and mycobacterial culture in the study laboratory. Confirmed smear-negative patients provided physiotherapy-assisted sputum and induced sputum, followed the next morning by gastric washing and bronchoalveolar lavage (BAL) samples.

RESULTS

A total of 150 patients diagnosed with smear-negative PTB by the hospital service were screened; 39 (26%) were smear-positive from supervised self-expectorated sputum examined in the study laboratory. The remaining 111 confirmed smear-negative patients were enrolled in the study; 89% were human immunodeficiency virus positive. Seven additional smear-positive cases were diagnosed using the augmented sputum collection techniques. No differences were observed in the numbers of cases detected using the different methods. Of the 46 smear-positive cases, 44 (95.6%) could be detected from self-expectorated and physiotherapy-assisted samples.

CONCLUSIONS

For countries such as Malawi, the best use of limited resources to detect smear-positive PTB cases would be to improve the quality of self-expectorated sputum collection and microscopy. The additional diagnostic yield using BAL after induced sputum is limited.

Doubts about DOTS

It’s too soon to say that direct observation of short courses of tuberculosis treatment is failing

Hypoadrenalism is not associated with early mortality during tuberculosis treatment in Malawi

SETTING

In the developing world, early mortality within 1 month of commencing tuberculosis (TB) treatment is high, particularly with human immunodeficiency virus (HIV) co-infection. In Malawi, 40% of those who die do so in the first month of treatment. Reasons remain unclear and may include delayed diagnosis, opportunistic infections, immune restoration inflammatory syndrome (IRIS) or malnutrition. One possible contributing factor is underlying hypoadrenalism associated with TB-HIV, exacerbated by rifampicin (RMP) induction of P450 and glucocorticoid metabolism.

OBJECTIVE

To assess the prevalence of hypoadrenalism in TB patients before and after commencement of TB treatment, and relationship with early mortality.

DESIGN

Prospective descriptive study assessing hypoadrenalism before and after anti-tuberculosis treatment, HIV status and outcome up to 3 months post-treatment.

RESULTS

Of 51 patients enrolled, 29 (56.9%) were female (median age 32 years, range 18-62). Of 43 patients HIV-tested, 38 (88.3%) were HIV-positive and 15.7% died within the first month. At 3 months, 11 (21.6%) were known to have died. Adequate cortisol levels were found in 49/51 (95.9%) before commencing RMP. Neither of the two with reduced response died. All 34 patients revealed adequate cortisol responses at 2 weeks.

CONCLUSION

No evidence of hypoadrenalism was found in this first study to assess adrenal function and outcome of anti-tuberculosis treatment.

The politics of TB: TB control services need tailoring for new arrivals, not vice versa

High rates of TB amongst new arrivals to the UK require flexible, innovative responses that go beyond traditional biomedical models and take into account the needs of these heterogeneous groups. This article explores the merging of public health and human rights based approaches to TB control in response to the challenge of increasing rates of TB amongst new arrivals in the UK.

Fluoroquinolones for treating tuberculosis

BACKGROUND

Fluoroquinolones are sometimes used to treat multiple-drug-resistant and drug-sensitive tuberculosis. The effects of fluoroquinolones in tuberculosis regimens need to be assessed.

OBJECTIVES

To assess fluoroquinolones as additional or substitute components to antituberculous drug regimens for drug-sensitive and drug-resistant tuberculosis.

SEARCH STRATEGY

In July 2007, we searched the Cochrane Infectious Diseases Group Specialized Register, CENTRAL (The Cochrane Library 2007, Issue 3), MEDLINE, EMBASE, LILACS, Science Citation Index, Database of Russian Publications, and metaRegister of Controlled Trials. We also scanned reference lists of all identified studies and contacted researchers.

SELECTION CRITERIA

Randomized controlled trials of antituberculous regimens containing fluoroquinolones in people diagnosed with bacteriologically positive (sputum smear or culture) pulmonary tuberculosis.

DATA COLLECTION AND ANALYSIS

Two authors independently applied inclusion criteria, assessed methodological quality, and extracted data. We used relative risk (RR) for dichotomous data, weighted mean difference (WMD) for continuous data (both with 95% confidence intervals (CI)), and the random-effects model if we detected heterogeneity and it was appropriate to combine data.

MAIN RESULTS

Eleven trials (1514 participants) met the inclusion criteria. No statistically significant difference was found in trials substituting ciprofloxacin, ofloxacin or moxifloxacin for first-line drugs in relation to cure (416 participants, 3 trials), treatment failure (388 participants, 3 trials), or clinical or radiological improvement (216 participants, 2 trials). Substituting ciprofloxacin into first-line regimens in drug-sensitive tuberculosis led to a higher incidence of relapse (RR 7.17, 95% CI 1.33 to 38.58; 384 participants, 3 trials) and longer time to sputum culture conversion (WMD 0.50 months, 95% CI 0.18 to 0.82; 168 participants, 1 trial), although this was confined to HIV-positive participants. Substituting for ethambutol in first-line regimens led to a higher incidence of total number of adverse events (RR 1.34, 95% CI 1.05 to 1.72; 492 participants, 2 trials). Adding or substituting levofloxacin to basic regimens in drug-resistant areas had no effect. A comparison of sparfloxacin versus ofloxacin added to regimens showed no statistically significant difference in cure (184 participants, 2 trials), treatment failure (149 participants, 2 trials), or the total number of adverse events (253 participants, 3 trials).

AUTHORS' CONCLUSIONS

Only ciprofloxacin, ofloxacin, levofloxacin, sparfloxacin and moxifloxacin have been tested in randomized controlled trials for treating tuberculosis. We cannot recommend ciprofloxacin in treating tuberculosis. Trials of newer fluoroquinolones for treating tuberculosis are needed and are on-going. No difference has been demonstrated between sparfloxacin and ofloxacin in drug-resistant tuberculosis.

Short-term bleach digestion of sputum in the diagnosis of pulmonary tuberculosis in patients co-infected with HIV

The bleach digestion of sputum may improve the yield of smear microscopy but has not been validated in patients with HIV. Therefore we assessed the performance of bleach-digested smear microscopy among patients with HIV. One thousand three hundred and twenty one patients with chronic cough submitted three sputum samples for direct smear microscopy and were offered HIV tests. One sample was selected for a bleach-digested smear and another one was cultured. Patients were classified as having 'definite' (>or=2 positive smears), 'very likely' (smear-negative, culture- positive), 'less likely' (one smear-positive, culture-negative) and 'unlikely' (smear and culture negative) tuberculosis (TB). In all, 566/1045 (54%) patients were HIV positive and 731/1186 (62%) were culture positive. The digested smears were positive in 123/125 (98%) 'definite', 4/118 (3%) 'very likely' and 1/174 'unlikely' TB patients with HIV and in 125/127 (98%) 'definite', 2/74 (3%) 'very likely', 4/4 'less likely' and 2/127 'unlikely' TB without HIV. Three direct smears identified 252 (57%) and one digested smear 254 (57%) of the 444 patients with 'definite' or 'very likely' TB. One bleach-digested smear performed similarly to three direct smears. Both methods were less sensitive in HIV-positive patients. Further studies are needed to compare the performance of the two methods under operational conditions.

Bleach-digested sputum smears for the diagnosis of TB in HIV-infected individuals

We describe the performance of bleach-digested Zeihl-Neelsen (ZN) smears in TB suspects with/without HIV. In total, 51 (26%) and 62 (31%) out of the first 198 spot and digested smears were positive. Seven of the 30 HIV-positive patients had TB and their ZN smears were negative, scanty or 1 +. Six of seven digested smears were scanty. Forty-two of 115 HIV-negative patients had TB. Eleven (26%) of their digested smears were negative, 12 (29%) scanty and 19 (45%) positive. Despite the lower bacilli numbers of HIV-positive patients, the technique had sensitivity and specificity similar to that in HIV-negative patients.

Developing a socio-economic measure to monitor access to tuberculosis services in urban Lilongwe, Malawi

OBJECTIVES

To develop locally appropriate measures of poverty for the National Tuberculosis Programme (NTP), Malawi, and to assess access to tuberculosis (TB) services by different socio-economic groups by establishing a socio-economic profile of current TB patients

DESIGN

A quantitative proxy measure of poverty was developed through regression analysis of data from the 1998 national Malawi Integrated Household Survey. A qualitative assessment of poverty was conducted in poor and non-poor settlements in urban Lilongwe to identify key indicators of socio-economic status. Both quantitative and qualitative indicators were used to assess the socioeconomic status of 179 TB patients who participated in a cross-sectional survey.

FINDINGS

The proxy measure of poverty and the qualitative indicators demonstrated similar ability to measure the poverty status of patients. The poverty head count among patients using the quantitative and qualitative indicators were 78% and 70%, respectively. Geographical analysis showed that 60% were from non-poor areas and only 15% (26/139) were from squatter settlements.

CONCLUSION

This study established a strategy for monitoring access to TB services using a proxy measure of poverty and qualitative indicators. This is a vital first step in developing an evidence base for pro-poor equitable TB services.

Providing HIV care for tuberculosis patients in sub-Saharan Africa

Human immunodeficiency virus (HIV)/acquired immunedeficiency syndrome (AIDS) and tuberculosis (TB) cause an immense burden of disease in sub-Saharan Africa. A large amount of knowledge has been gathered in the last 15 years about the negative impact that HIV has on TB control, both at a programme level and at the level of the individual patient. Equally, interventions that are known to benefit patients have been tested and piloted, and these form important components of international TB-HIV guidelines, a TB-HIV strategic framework and an interim policy on TB-HIV coordination. Unfortunately, in sub-Saharan Africa there is little evidence that these interventions are being implemented on the ground, and one of the reasons for this paralysis is that the operational details are not well developed. This paper takes the three important HIV interventions of HIV testing and counselling, cotrimoxazole preventive treatment and antiretroviral treatment, and discusses some of the practical details of on-the-ground implementation. We hope that this will generate discussion, but above all, the impetus to start delivering services to patients.

Screening for pulmonary tuberculosis: an acceptable intervention for antenatal care clients and providers?

SETTING

Five purposively sampled health facilities in Kasungu District, Malawi.

OBJECTIVES

To explore 1) the acceptability of introducing pulmonary tuberculosis (PTB) screening into antenatal care (ANC) clinics amongst ANC clients and ANC service providers; and 2) the acceptability of tuberculosis (TB) treatment during and after pregnancy among women registered for TB treatment.

METHODS

Fourteen focus group discussions and 40 in-depth interviews with ANC clients (15), ANC service providers (10) and women registered for TB treatment (15).

RESULTS

Most clients found the introduction of PTB screening into ANC clinics acceptable. Some expressed concern at submitting a second sputum specimen, citing transportation/distance as the main obstacle. Other concerns were stigma and fear relating to the human immunodeficiency virus and the acquired immune-deficiency syndrome (HIV/AIDS) and taking TB treatment during pregnancy and breast-feeding. All ANC service providers supported the idea, but were concerned about increased workload.

CONCLUSION

PTB screening in the ANC setting would be an acceptable intervention and could serve to increase PTB case notification in Malawi. However, alternative diagnostic strategies need to be explored. The negative associations with HIV/AIDS and some of the misconceptions surrounding TB treatment need to be addressed to avoid PTB screening becoming a potential barrier to seeking ANC. The main challenge will be whether over-stretched staff will be able to cope with this additional service.

The bleach microscopy method and case detection for tuberculosis control

The World Health Organization (WHO) and the International Union Against Tuberculosis and Lung Disease (The Union) recommend direct sputum smear microscopy for tuberculosis (TB) case finding in resource-poor settings. This method is associated with poor sensitivity. Digestion of sputum with bleach prior to smear preparation has been reported to increase sensitivity. Some workers, having reviewed the relevant literature, have called for the WHO and The Union to advocate for a shift to this methodology for TB case finding. This article highlights deficiencies in the scope and detail of available evidence, and cautions against the premature, and possibly counter-productive, adoption of so-called 'bleach microscopy'. Further well-guided research is required to answer policy-relevant gaps in our knowledge about this promising technology.

A one-day method for the diagnosis of pulmonary tuberculosis in rural Ethiopia

Smear diagnosis of pulmonary tuberculosis (PTB) requires three sputum examinations over 2 days. We evaluated the performance of two sputum specimens obtained on a single day (the second specimen submitted 1 h after the first) against the standard 2-day method in rural Ethiopia. A total of 243 suspects were enrolled; 52 had confirmed PTB: 49 (94%) were detected by the same-day method and 51 (98%) by the standard method (P > 0.5). The same-day approach would reduce the number of visits required for diagnosis, save resources for the health system and the patient, and ultimately improve case detection in poorer countries.

Microbiological validation of smear microscopy after sputum digestion with bleach; a step closer to a one-stop diagnosis of pulmonary tuberculosis

BACKGROUND

Smear microscopy is relatively insensitive for the diagnosis of TB. The digestion of sputum with household bleach prior to smear preparation has been reported to improve its sensitivity. This method has not been validated.

METHODS

Seven hundred and fifty six patients with symptoms suggestive of pulmonary TB (PTB) were asked to submit 3 sputum specimens for direct microscopy. One specimen was selected at random for culture and another specimen was digested to prepare a further smear. The WHO case definition (>or=2 positive smears or one positive smear and positive culture) was used to compare the sensitivity and specificity of the smears.

FINDINGS

Four hundred and fifty five (60%) patients were culture-positive. Of these, 235 (31%) had "definite" PTB and 223 (29%) "very likely" PTB (smear-negative, culture-positive). The WHO case definition identified 51% (235/458) of the patients with "definite" or "very likely" PTB. One digested smear detected 219 (93%) of the 235 patients with "definite" PTB and 10 patients with "very likely" PTB (sensitivity (95%CI) 50% (45-55%); specificity 99% (97-100%)). The positive and negative predictive values for one digested smear were 98% (95-99%) and 56% (52-60%) respectively, which were not different (p>0.5) to the WHO case definition (100% and 57%, respectively).

INTERPRETATION

One bleach-digested smear is as sensitive and specific as the WHO case definition for the diagnosis of PTB.

Comparison of scanty AFB smears against culture in an area with high HIV prevalence

To verify among tuberculosis (TB) suspects attending hospitals in Abuja, Nigeria, if sputum smears graded as scanty are false-positive, sputum smears from 1068 patients were graded with the International Union Against Tuberculosis and Lung Disease classification. One specimen was cultured. Eight hundred and twenty-four (26%) smears were positive, 137 (4%) scanty and 2243 negative. Of 1068 cultures, 680 (64%) were positive. One hundred and thirty (95%) scanty and 809 (98%) positive smears were culture-positive. Twelve of 18 patients with a single scanty smear and 51 of 52 with > or = 2 scanty smears were culture-positive. Fewer than < 5% scanty results, < 1% of the patients treated for TB, are false-positive.

Fluoroquinolones for treating tuberculosis

BACKGROUND

Fluoroquinolones are sometimes used to treat multiple-drug-resistant and drug-sensitive tuberculosis. The effects of fluoroquinolones in tuberculosis regimens need to be assessed.

OBJECTIVES

To assess fluoroquinolones as additional or substitute components to antituberculous drug regimens for drug-sensitive and drug-resistant tuberculosis.

SEARCH STRATEGY

We searched the Cochrane Infectious Diseases Group Specialized Register (April 2005), CENTRAL (The Cochrane Library Issue 1, 2005), MEDLINE (1966 to April 2005), EMBASE (1974 to April 2005), LILACS (1982 to April 2005), Science Citation Index (1940 to April 2005), and Russian database (1988 to April 2005). We also scanned reference lists of all identified studies and contacted researchers.

SELECTION CRITERIA

Randomized controlled trials of antituberculous regimens containing fluoroquinolones in people diagnosed with bacteriologically positive (sputum smear or culture) pulmonary tuberculosis.

DATA COLLECTION AND ANALYSIS

Two authors independently applied inclusion criteria, assessed methodological quality, and extracted data. We used relative risk (RR) for dichotomous data, weighted mean difference (WMD) for continuous data (both with 95% confidence intervals (CI)), and the random-effects model if we detected heterogeneity and appropriate to combine data.

MAIN RESULTS

Ten trials (1178 participants) met the inclusion criteria. No statistically significant difference was found in trials substituting ciprofloxacin or ofloxacin for first-line drugs in relation to cure (89 participants, 2 trials), treatment failure (388 participants, 3 trials), or clinical or radiological improvement (216 participants, 2 trials). Substituting ciprofloxacin into first-line regimens in drug-sensitive tuberculosis led to a higher incidence of relapse (RR 7.17, 95% CI 1.33 to 38.58; 384 participants, 3 trials) and longer time to sputum culture conversion (WMD 0.50 months, 95% CI 0.18 to 0.82; 168 participants, 1 trial), although this was confined to HIV-positive participants. Adding or substituting levofloxacin to basic regimens in drug-resistant areas had no effect. A comparison of sparfloxacin versus ofloxacin added to regimens showed no statistically significant difference in cure (184 participants, 2 trials), treatment failure (149 participants, 2 trials), or total number of adverse events (253 participants, 3 trials).

AUTHORS' CONCLUSIONS

Only ciprofloxacin, ofloxacin, levofloxacin, and sparfloxacin have been tested in randomized controlled trials for treating tuberculosis. We cannot recommend ciprofloxacin in treating tuberculosis. Trials of newer fluoroquinolones for treating tuberculosis are needed. No difference has been demonstrated between sparfloxacin and ofloxacin in drug-resistant tuberculosis.

'Lost' smear-positive pulmonary tuberculosis cases: where are they and why did we lose them?

SETTING

Ntcheu District, rural Malawi.

OBJECTIVES

1) To locate smear-positive pulmonary tuberculosis patients who were identified during the first 6 months of 2000 but did not start treatment ('lost cases'); 2) to describe these patients' pathways to diagnosis, health status and socio-demographic characteristics; and 3) to explore why these patients did not start treatment.

METHODS

Lost cases were traced from programme registers and interviewed using the qualitative research critical incidents narrative (CIN) interviews technique. Results were triangulated with responses from health care workers through focus group discussions.

RESULTS

The laboratory registered 157 new smear-positive patients. Twenty three (15%) of these were 'lost' (did not appear in the treatment register). CIN interviews were conducted with five lost patients and 14 carers of lost patients who had died. Long pathways to diagnosis were the norm. Health system structural barriers were the main factors behind these pathways, including requirement for hospital attendance, delays in symptom recognition and receipt of sputum results, and the misconception that negative smears excluded tuberculosis.

CONCLUSION

Some smear-positive cases experience very long pathways to diagnosis and are lost from this free public health system. The diagnostic process needs to become more responsive to patients' needs.

Using a bus service for transporting sputum specimens to the Central Reference Laboratory: effect on the routine TB culture service in Malawi

SETTING

All non-private hospitals in Malawi that registered TB cases in 2001, during which there was a bus service for transporting sputum specimens to the Central Reference Laboratory (CRL) for mycobacterial culture and drug sensitivity testing (CDST).

OBJECTIVES

To determine the performance of the system of collecting and processing sputum specimens from patients with recurrent smear-positive pulmonary TB through to CDST.

DESIGN

Structured interviews with TB Officers, and retrospective data collection using TB and laboratory registers.

RESULTS

There were 964 patients with recurrent smear-positive PTB. TB Officers took responsibility for collecting and transporting sputum to the CRL, and 73% reported using the bus service. Sputum specimens from 384 (40%) patients arrived at the CRL. Of these, 40% were found to have negative concentrated smears at the CRL, and 36% of specimen sets arriving at CRL were successfully cultured for DST. Most specimens had been collected after the start of anti-tuberculosis treatment. Although delays in collection adversely affected culture, only 43% of specimen sets collected on or before the first day of treatment yielded Mycobacterium tuberculosis.

CONCLUSION

Problems were identified at all stages of the system and strategies to remedy these are being put in place.

Characteristics, management and outcome of patients with recurrent tuberculosis under routine programme conditions in Malawi

SETTING

All 43 non-private hospitals in Malawi, which registered TB cases between 1 July 1999 and 30 June 2000.

OBJECTIVES

To determine 1) the characteristics, management and treatment outcome, 2) timing of the previous episode of TB, and 3) pattern of drug resistance in patients registered with recurrent smear-positive pulmonary TB.

DESIGN

Retrospective data collection using TB registers and laboratory culture and drug sensitivity registers.

RESULTS

There were 748 recurrent patients; data were available for 747. Of these, 487 (65%) successfully completed a re-treatment regimen, 185 (25%) died and the remainder had another outcome. Information about previous TB was recorded for 491 (66%) patients. In 286 (58%) there were 2 years or less between completing and re-starting treatment. Only 307 (41%) patients had sputum sent for culture and drug sensitivity tests. In 164 patients with cultures of Mycobacterium tuberculosis, 122 (81%) were fully sensitive, 25 (15%) had resistance to isoniazid and/or streptomycin, and 6 (4%) had resistance to isoniazid and rifampicin (MDR-TB).

CONCLUSION

Patients with recurrent TB had acceptable treatment outcomes, and most had fully sensitive organisms. Over half had recurrent TB 2 years or less after completing treatment. Ways to prevent recurrence need to be investigated and implemented in the field.