Access to quality diagnosis and rational treatment for tuberculosis: real-world evidence from China-Gates Tuberculosis Control Project Phase III.

BACKGROUND: China has successfully reduced tuberculosis (TB) incidence rate over the past three decades, however, challenges remain in improving the quality of TB diagnosis and treatment. In this paper, we assess the effects of the implementation of "China National Health Commission (NHC) and Gates Foundation TB Prevention and Control Project" on the quality of TB care in the three provinces. METHODS: We conducted the baseline study in 2016 and the final evaluations in 2019 in the 12 selected project counties. We obtained TB patients' information from the TB Information Management System and reviewed medical records of TB cases in the TB designated hospitals. We compared TB diagnosis and treatment services with the national practice guideline and used Student's t-test and Pearson χ2 tests or Fisher's exact tests to compare the difference before and after the project implementation. RESULTS: The percentage of sputum smear-negative (SS-) patients taking culture or rapid molecular test (RMT) doubled between 2015 and 2018 (from 35% to 87%), and the percentage of bacteriologically confirmed pulmonary TB cases increased from 36% to 52%. RMT has been widely used and contributed an additional 20% of bacteriologically confirmed TB cases in 2018. The percentage of TB patients taking drug susceptibility tests (DST) also doubled (from 40% in 2015 to 82% in 2018), and the proportion of TB patients receiving adequate diagnosis services increased from 85% to 96%. Among all SS- TB patients, over 86% received the recommended diagnostic services at the end of the study period, an improvement from 75% prior to the project implementation. However, the proportion of TB patients treated irrationally using second-line anti-TB drugs (SLDs) increased from 12.6% in 2015 to 19.9% in 2018. The regional disparities remained within the project provinces, albeit the gaps between them narrowed down for almost all indicators. CONCLUSIONS: The quality of TB diagnosis services has been improved substantially, which is attributable to the coverage of new diagnosis technology. However, irrational use of SLDs remains a concern after the project implementation.

Prolonged use of bedaquiline in two patients with pulmonary extensively drug-resistant tuberculosis: Two case reports.

BACKGROUND: Bedaquiline is among the prioritized drugs recommended by the World Health Organization for the treatment of extensively drug-resistant tuberculosis (XDR-TB). Many patients have not achieved better clinical improvement after bedaquiline is stopped at 24 wk. However, there is no recommendation or guideline on bedaquiline administration beyond 24 wk, which is an important consideration when balancing the benefit of prognosis for XDR-TB against the uncertain safety concerning the newer antibiotics. CASE SUMMARY: This paper reported 2 patients with XDR-TB (a female of 58 years of age and a female of 18 years of age) who received bedaquiline for 36 wk, as local experience to be shared. The 2 cases had negative cultures after 24 wk of treatment, but lung imaging was still positive. After discussion among experts, the consensus was made to bedaquiline prolongation by another 12 wk. The 36-wk prolonged use of bedaquiline in both cases achieved a favorable response without increasing the risk of cardiac events or new safety signals. CONCLUSION: Longer regimen, including 36-wk bedaquiline treatment, might be an option for patients with XDR-TB. More studies are needed to explore the effectiveness and safety of prolonged use of bedaquiline for 36 wk vs standard 24 wk in the treatment of multidrug-resistant/XDR-TB or to investigate further the biomarkers and criteria indicative for extension of bedaquline to facilitate clinical use of this novel drug.

Impacts of a comprehensive tuberculosis control model on the quality of clinical services and the financial burden of treatment for patients with drug-resistant tuberculosis in China: a mixed-methods evaluation.

BACKGROUND: The China National Health Commission-Gates TB Project Phase III implemented a comprehensive TB control model including multiple interventions to address the burden of drug-resistant TB (DRTB). This study aims to evaluate the quality of DRTB clinical services and assess the financial burden of DRTB patients during the intervention period. METHODS: A mixed-methods approach was used to evaluate the effectiveness of interventions in the three project provinces: Zhejiang, Jilin and Ningxia Hui Autonomous Region. The quantitative data included de-identified DRTB registry data during 2015-2018 in project provinces from China CDC, medical records of DRTB patients registered in 2018 (n = 106) from designated hospitals, and a structured DRTB patient survey in six sample prefectures in 2019. The quality of clinical services was evaluated using seven indicators across patient screening, diagnosis and treatment. Logistic regression was conducted to explore factors associated with the extremely high financial burden. Semi-structured in-depth interviews with policymakers and focus group discussions with physicians and DRTB patients were conducted to understand the interventions implemented and their impacts. RESULTS: The percentage of bacterially confirmed patients taking a drug susceptibility test (DST) increased significantly between 2015 and 2018: from 57.4 to 93.6% in Zhejiang, 12.5 to 86.5% in Jilin, and 29.7 to 91.4% in Ningxia. The treatment enrollment rate among diagnosed DRTB patients also increased significantly and varied from 73 to 82% in the three provinces in 2018. Over 90% of patients in Zhejiang and Jilin and 75% in Ningxia remained in treatment by the end of the first six months' treatment. Among all survey respondents 77.5% incurred extremely high financial burden of treatment. Qualitative results showed that interventions on promoting rapid DST technologies and patient referral were successfully implemented, but the new financing policies for reducing patients' financial burden were not implemented as planned. CONCLUSIONS: The quality of DRTB related clinical services has been significantly improved following the comprehensive interventions, while the financial burden of DRTB patients remains high due to the delay in implementing financing policies. Stronger political commitment and leadership are required for multi-channel financing to provide additional financial support to DRTB patients.

Bedaquiline-containing regimens in patients with pulmonary multidrug-resistant tuberculosis in China: focus on the safety.

BACKGROUND: World Health Organization recommends countries introducing new drug and short treatment regimen for drug resistant tuberculosis (DR-TB) should develop and implement a system for active pharmacovigilance that allows for detection, reporting and management of adverse events. The aim of the study is to evaluate the frequency and severity of adverse events (AEs) of bedaquiline-containing regimen in a cohort of Chinese patients with multidrug-resistant (MDR)/extensively drug-resistant (XDR)-TB based on active drug safety monitoring (aDSM) system of New Drug Introduction and Protection Program (NDIP). METHODS: AEs were prospectively collected with demographic, bacteriological, radiological and clinical data from 54 sites throughout China at patient enrollment and during treatment between February, 2018 and December, 2019. This is an interim analysis including patients who are still on treatment and those that have completed treatment. A descriptive analysis was performed on the patients evaluated in the cohort. RESULTS: By December 31, 2019, a total of 1162 patients received bedaquiline-containing anti-TB treatment. Overall, 1563 AEs were reported, 66.9% were classified as minor (Grade 1-2) and 33.1% as serious (Grade 3-5). The median duration of bedaquiline treatment was 167.0 [interquartile range (IQR): 75-169] days. 86 (7.4%) patients received 36-week prolonged treatment with bedaquiline. The incidence of AEs and serious AEs was 47.1% and 7.8%, respectively. The most frequently reported AEs were QT prolongation (24.7%) and hepatotoxicity (16.4%). There were 14 (1.2%) AEs leading to death. Out of patients with available corrected QT interval by Fridericia's formula (QTcF) data, 3.1% (32/1044) experienced a post-baseline QTcF ≥ 500 ms, and 15.7% (132/839) had at least one change of QTcF ≥ 60 ms from baseline. 49 (4.2%) patients had QT prolonged AEs leading to bedaquiline withdrawal. One hundred and ninety patients reported 361 AEs with hepatotoxicity ranking the second with high occurrence. Thirty-four patients reported 43 AEs of hepatic injury referred to bedaquiline, much lower than that referred to protionamide, pyrazinamide and para-aminosalicylic acid individually. CONCLUSIONS: Bedaquiline was generally well-tolerated with few safety concerns in this clinical patient population without any new safety signal identified. The mortality rate was generally low. These data inform significant positive effect to support the WHO recent recommendations for the wide use of bedaquiline.

Performance of the Xpert® MTB/RIF assay in the rapid diagnosis of tracheobronchial tuberculosis using bronchial washing fluid.

OBJECTIVE: To assess the diagnostic value of the Xpert® MTB/RIF (GeneXpert) assay for tracheobronchial tuberculosis (TBTB) using bronchial washing fluid (BWF). METHODS: This retrospective study enrolled patients suspected of having TBTB and patients with non-TB pulmonary disease as controls. BWF were used to undertake acid-fast bacillus (AFB) smears, the GeneXpert assay and the LÓ§wenstein-Jensen (LJ) culture method. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were compared among BWF AFB smears, BWF GeneXpert and the BWF LJ culture method. RESULTS: A total of 130 patients with TBTB and 102 patients with non-TB pulmonary disease were enrolled in the study. Sputum AFB smears were positive in 62 of 130 patients (47.7%) with TBTB. Using the clinical diagnosis of TBTB as the gold standard, the sensitivity, specificity, PPV and NPV of the three methods using BWF were as follows: 93.1%, 99.0%, 99.2% and 91.8% for BWF GeneXpert; 73.1%, 100.0%, 100.0% and 74.5% for BWF LJ cultures; 53.8%, 99.0%, 98.6% and 62.7% for BWF AFB smears. The diagnostic yield of BWF GeneXpert was significantly higher compared with BWF cultures for type III and IV TBTB. CONCLUSION: The Xpert® MTB/RIF assay using BWF exhibited higher sensitivity than bacteriological diagnostic methods and was particularly useful for the early diagnosis of smear-negative TBTB.

Diagnostic Value of Cerebrospinal Fluid T-SPOT.TB for Tuberculousis Meningitis in China.

The aim of this study was to evaluate the diagnostic value of the cerebrospinal fluid (CSF) T-SPOT.TB test for the diagnosis of TB meningitis (TBM). A retrospective analysis of 96 patients with manifested meningitis was conducted; T-SPOT.TB test was performed for diagnosing TBM to determine the diagnostic sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). A receiver operating characteristic (ROC) curve was also drawn to assess the diagnostic accuracy. The sensitivity, specificity, PPV, and NPV of CSF T-SPOT.TB test were 97.8%, 78.0%, 80.3%, and 97.5%, respectively, for 52 patients (54.2%) of the 96 enrolled patients. The area under the curve (AUC) was 0.910, and the sensitivities of CSF T-SPOT.TB for patients with stages I, II, and III of TBM were 96.7%, 97.2%, and 98.9%, respectively. CSF T-SPOT.TB test is a rapid and accurate diagnostic method with higher sensitivity and specificity for diagnosing TBM.

Case Report: Primary Tuberculosis of the Bilateral Breast.

Primary breast tuberculosis is rare. We report a case of bilateral primary breast tuberculosis. The patient received incisional drainage and debridement of both breasts. Histopathology of the breast tissues revealed chronic granulomatous inflammation and positive acid-fast stain. The patient received antitubercular therapy for 18 months, and she achieved complete resolution.

Preclinical study and phase I clinical safety evaluation of recombinant Mycobacterium tuberculosis ESAT6 protein.

BACKGROUND: To investigate the ability of rESAT6 to identify different mycobacteria-sensitized guinea pigs and its safety in preclinical and phase I clinical study. MATERIAL AND METHODS: Guinea pigs were sensitized with different Mycobacteria. After sensitization, all animals were intradermally injected with rESAT6 and either PPD or PPD-B. At 24 h after the injection, the erythema of the injection sites were measured using a double-blind method. For the preclinical safety study, different doses of rESAT6 and BSA were given 3 times intramuscularly to guinea pigs. On day 14 after the final immunization, the guinea pigs were intravenously injected with the same reagents in the hind legs and the allergic reactions were observed. A single-center, randomized, open phase I clinical trial was employed. The skin test was conducted in 32 healthy volunteers aged 19-65 years with 0.1 µg, 0.5 µg, and 1 µg rESAT6. Physical examination and laboratory tests were performed before and after the skin test and adverse reactions were monitored. The volunteers' local and systemic adverse reactions and adverse events were recorded for 7 days. RESULTS: Positive PPD or PPD-B skin tests were observed in all Mycobacteria-sensitized guinea pigs; the diameters of erythema were all >10 mm. The rESAT6 protein induced a positive skin test result in the guinea pigs sensitized with MTB, M. bovis, M. africanum and M. kansasii; the diameters of erythema were 14.7±2.0, 9.3±3.8, 18.7±2.4, and 14.8±4.2 mm, respectively. A negative skin test result was detected in BCG-vaccinated and other NTM-sensitized guinea pigs. The rESAT6 caused no allergic symptoms, but many allergic reactions, such as cough, dyspnea, and even death, were observed in the guinea pigs who were administered BSA. During the phase I clinical trial, no adverse reactions were found in the 0.1 µg rESAT6 group, but in the 0.5 µg rESAT6 group 2 volunteers reported pain and 1 reported itching, and in the 1 µg rESAT6 group there was 1 case of pain, 1 case of itching, and 1 case of blister. No other local or systemic adverse reactions or events were reported. CONCLUSIONS: The rESAT6 can differentiate effectively among MTB infection, BCG vaccination, and NTM infection and is safe in healthy volunteers.

[Comparison of two interferon-gamma release assays in the diagnosis of tuberculosis].

OBJECTIVE: To compare the diagnostic performance of A.TB, an ELISA-based interferon-gamma release assay (IGRA), and T-SPOT.TB, an ELISPOT-based IGRA, and therefore to evaluate the value of A.TB assay in the routine clinical practice. METHODS: From March to May of the year of 2011, 112 hospitalized patients were enrolled from 2 chest hospitals in Beijing and Harbin, including 75 cases in the TB group (43 male and 32 female) with the average age of (44 ± 18) years, spanning from 28 to 57 years, and 37 cases in the non-TB group (21 male and 16 female) with the average age of (54 ± 10) years, spanning from 24 to 82 years. During the same period, 34 healthy volunteers (4 male and 30 female), with the average age of (20 ± 0.6) years, spanning from 19 to 22 years, were recruited in Beijing Chest Hospital. A head-to-head comparison of the 2 IGRAs was performed on the 146 subjects to evaluate their overall diagnostic performance. Chi-square test or Fisher's exact test was used for statistical analysis of enumeration data. RESULTS: The sensitivity and specificity of A.TB were 81.3% (61/75, 95%CI = 72.5 - 90.2) and 83.1% (59/71, 95%CI = 74.4 - 91.8) respectively, compared to 90.7% (68/75, 95%CI = 84.1 - 97.3) and 78.9% (56/71, 95%CI = 69.4 - 88.4) for T-SPOT.TB. There was no significant difference in sensitivity or specificity (chi square values were 2.77 and 0.17 respectively, both P > 0.05). The area under the ROC curve was 0.90 (95%CI = 0.84 - 0.95) for A.TB and 0.91 (95%CI = 0.86 - 0.96) for T-SPOT.TB. The observation agreement between the 2 methods was 87.2% (123/141), with a kappa value of 0.74. T-SPOT.TB produced indeterminate results at a rate of 3.4% (5/146). CONCLUSIONS: There was comparable diagnostic performance between the 2 assays. However, when compared to T-SPOT.TB, the A.TB testing procedure, with less technical demand and without requirement of well-equipped lab, is simpler and the interpretation of results is less subjective.

[Role of enzyme-linked immunospot assay and tuberculin skin test in the auxiliary diagnosis of initial pulmonary tuberculosis].

OBJECTIVE: To compare enzyme-linked immunospot assay (ELISPOT) and tuberculin skin test (TST) and explore their roles in the auxiliary diagnosis of initial pulmonary tuberculosis. METHODS: Totally 123 patients with initial pulmonary tuberculosis (tuberculosis group) and 102 patients with non-tuberculosis pulmonary disease (control group) were enrolled. The peripheral blood mononuclear cells of all participants were co-cultured with early secretiny antigen target-6/culture filtrate protein-10 fusion protein (ESAT-6/CFP-10), and spot forming cells (SFCs) were enumerated by ELISPOT (ESAT-6/CFP-10-ELISPOT). TST was also performed simultaneously. RESULTS: ESAT-6/CFP-10-ELISPOT showed significantly higher numbers of SFCs after stimulation in tuberculosis group than in control group (P = 0.000). The sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, positive predictive value, and negative predictive value of ESAT-6/CFP-10-ELISPOT were 91.1% (111/123), 81.4% (82/102), 4.60, 0.12, 0.85, and 0.87 respectively, while the above values of TST were 65.6% (59/90), 45.1% (46/102), 1.31, 0.76, 0.51, and 0.60, respectively. The sensitivity and specificity of ESAT-6/CFP-10-ELISPOT were significantly higher than those of TST (all P = 0.000). The number of SFCs were not significantly different between smear-positive tuberculosis subgroup and smear-negative tuberculosis subgroup (P = 0.166). The sensitivities were 91.8% (67/73) and 88.0% (44/50) in these two subgroups, respectively, (P = 0.448). CONCLUSIONS: ESAT-6/CFP-10-ELISPOT may be a more accurate approach for the auxiliary diagnosis of initial pulmonary tuberculosis; meanwhile, it offers certain diagnostic evidences for smear-negative tuberculosis. However, its specificity may be affected by latent tuberculosis infection. On the contrary, TST has poor value in the auxiliary diagnosis of initial pulmonary tuberculosis.

[The comparison of different antigens in enzyme-linked immunospot assay for the diagnosis of tuberculosis.].

OBJECTIVE: To compare different Mycobacterium tuberculosis antigens in enzyme-linked immunospot assay (ELISPOT) for the auxiliary diagnosis of active tuberculosis. METHODS: The peripheral blood mononuclear cells (PBMC) from patients with tuberculosis and controls were co-cultured with the following antigens: purified protein derivative (PPD), early secretory antigenic target-6 (ESAT-6) and early secretory antigenic target-6/culture filtrate protein-10 fusion protein (ESAT-6/CFP-10). Spot forming cells (SFC) were enumerated by ELISPOT. RESULTS: PPD-ELISPOT, E/C-ELISPOT and ESAT-6-ELISPOT showed significantly higher SFC counts in active tuberculosis [255(93-526), 148(40-354) and 28(10-116) respectively] as compared to the controls [10(5-41), 10(0-20) and 5(0-15) respectively], u values were 1479.5, 1390.5 and 2510.5 respectively, all P < 0.01. Compared with the sensitivity of ESAT-6-ELISPOT (62.1%), that of E/C-ELISPOT and PPD-ELISPOT was higher (90.3% and 84.8%), chi(2) = 17.496 and 28.541, all P < 0.01. Compared with the specificity of PPD-ELISPOT (68.9%), that of E/C-ELISPOT and ESAT-6-ELISPOT was also higher (84.4% and 88.9%), chi(2) = 6.807 and 10.808, P < 0.05 and P < 0.01 respectively. CONCLUSIONS: E/C-ELISPOT is a promising approach to the auxiliary diagnosis of tuberculosis, but its specificity could be affected by latent tuberculosis infection.

[A study on in vitro and in vivo models of Mycobacterium tuberculosis persistence].

OBJECTIVE: To establish in vivo and in vitro models of persistent Mycobacterium tuberculosis infection, and therefore to study the persisters in different conditions and periods of chemotherapy, and to explore the relationship between the persisters and chemotherapy. METHODS: The persisters in the two models were examined by culturing Mycobacterium tuberculosis in oxygen-starved condition and determining the mRNA expression of isocitrate lyase (ICL), alpha-crystallin chaperone (Acr) and 85B through quantitative PCR. RESULTS: The bacteria which could be cultured in oxygen-starved condition were discovered in both models. The mRNA expression of ICL and Acr increased gradually and dramatically after culture for 4 days in the in vitro model, their values being (5.3 +/- 0.9) and (6.4 +/- 1.6) log copy/ml respectively. While the mRNA expression of 85B showed no significant change in oxygen-starved condition, it increased significantly in the standard condition, the values being (6.1 +/- 0.9) log copy/ml at 10th day. In the mice infected with Mycobacterium tuberculosis, the mRNA expression of ICL was detected in 2 and 4 weeks post-infection, and decreased 4 weeks after treatment. The Acr mRNA showed no or very low expression 4 weeks post-infection or 4 weeks after treatment, but it increased significantly 8 and 10 weeks after treatment, with a value of (6.2 +/- 1.7) log copy/ml at 10 weeks, and its expression was still detected 12 weeks after treatment and 4 weeks after the cessation of treatment [(3.0 +/- 1.6) log copy/ml]. The expression of 85B mRNA was high before the treatment [(6.4 +/- 1.1) log copy/ml], and decreased gradually during the therapy. CONCLUSION: The models of in vitro and in vivo persistence of Mycobacterium tuberculosis were established. ICL and Acr mRNAs were highly expressed, which may be the markers of persisters. Persisters can be detected by culture in oxygen-starved conditions and the measurement of mRNA expression.

[The clinical significance of serum tuberculosis specific antigen antibody in the diagnosis of tuberculosis].

OBJECTIVE: To evaluate the significance of serum tuberculosis specific antigen (TB-SA) antibody detection in the diagnosis of tuberculosis. METHODS: TB-SA antibody in the serum samples from 829 cases of tuberculosis, 278 patients with non-tuberculosis lung diseases and 125 healthy volunteers were detected using enzyme-linked immunosorbent assay (ELISA). Tuberculosis was confirmed by clinical, bacteriology, X-ray examination and pathology studies. RESULTS: The sensitivity of TB-SA antibody in diagnosis of bacteriologically positive and negative pulmonary tuberculosis and extrapulmonary tuberculosis was 75.1% (272/362), 68.9% (226/328) and 71.2% (99/139), respectively; the combined sensitivity was 72.0% (597/829), and the specificity 82.1% (331/403). The relationship between the OD(405) of TB-SA antibody and PPD positivity showed no linear relationship, suggesting that BCG vaccination did not affect the value of serum TB-SA antibody. CONCLUSION: The results suggest that measurement of serum TB-SA is a relatively sensitive and specific method for the diagnosis and differential diagnosis of tuberculosis.