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INTRODUCTION: The intensification of research and innovation with the creation of networks of rapid and effective molecular tests as strategies for the end of tuberculosis are essential to avoid late diagnosis and for the eradication of the disease. We aimed to evaluate the cost-effectiveness of Xpert®MTB/RIF (Xpert) in the diagnosis of drug-resistant tuberculosis in reference units, in scenarios with and without subsidies, and the respective cost adjustment for today. METHODS: The analyses were performed considering as criterion of effectiveness, negative culture or clinical improvement in the sixth month of follow-up. The comparison was performed using two diagnostic strategies for the drug susceptibility test (DST), BactecTMMGITTM960 System, versus Xpert. The cost effectiveness and incremental cost-effectiveness ratio (ICER) were calculated and dollar-corrected for American inflation (US$ 1.00 = R$ 5,29). RESULTS: Subsidized Xpert had the lowest cost of US$ 33.48 (R$67,52) and the highest incremental average efficiency (13.57), thus being a dominated analysis. After the inflation was calculated, the mean cost was DST-MGIT=US$ 74.85 (R$ 396,73) and Xpert = US$ 37.33 (R$197,86) with subsidies. CONCLUSIONS: The Xpert in the diagnosis of TB-DR in these reference units was cost-effective with subsidies. In the absence of a subsidy, Xpert in TB-DR is not characterized as cost effective. This factor reveals the vulnerability of countries dependent on international organizations’ subsidy policies.

Background Mycobacterium tuberculosis infection is known to cause inflammation and lung tissue damage in high-risk populations. Nevertheless, direct associations between mycobacterial loads, systemic inflammation and pulmonary lesions upon treatment initiation have not been fully characterized. In the present exploratory study, we prospectively depict the immune profile, microbial clearance and evolution of radiographic lesions in a pulmonary tuberculosis (PTB) patient cohort before and 60 days after anti-tuberculous treatment (ATT) initiation. Methods Circulating levels of cytokines (IL-2, IL-4, IL-6, IL-10, IFN-γ, TNF-α) and C-reactive protein (CRP), as well as values of erythrocyte sedimentation rate (ESR) were measured in cryopreserved serum samples obtained from 73 PTB patients at pre-ATT and day 60 of treatment. Changes of the immune profile over time were compared with mycobacterial loads in sputum and culture conversion at day 60 of ATT. Additional analyses tested associations between improvement of chest radiographic lesions at day 60 and pre-treatment status of inflammation and mycobacterial loads. Results Within the inflammatory parameters evaluated, values of CRP, IL-2, IL-4, TNF-α and ESR significantly decreased upon treatment initiation. On the converse, IL-10 levels substantially increased at day 60 of ATT, whereas concentrations of IL-6 and IFN-γ remained unchanged. Multidimensional analyses revealed that ESR, IL-2, IL-4 and CRP were the parameters with the highest power to discriminate individuals before and after treatment initiation. We further demonstrated that higher bacterial loads in sputum at pre-ATT were associated with increased systemic inflammation and higher risk for positive M. tuberculosis sputum cultures at day 60 of treatment. Furthermore, we found that pre-ATT mycobacterial loads in sputum and systemic inflammation synergistically associated with the status of radiographic lesions during treatment (Relative risk for chest X-ray improvement: 10.0, 95 % confidence interval: 2.4–40.0, P = 0.002). Conclusions M. tuberculosis loads in sputum are directly associated to the status of systemic inflammation and potentially impact the immune profile, culture conversion and evolution of lung lesions upon ATT initiation. Electronic supplementary material The online version of this article (doi:10.1186/s12879-016-1736-3) contains supplementary material, which is available to authorized users.