Retrospective analysis of the clinical utility of multi-cytokine profiles in smear-negative pulmonary tuberculosis.

OBJECTIVES: To evaluate cytokine profiles and interferon-gamma release assay (IGRA) for their diagnostic capabilities in the differentiation of tuberculosis (TB) from non-TB conditions, as well as smear-negative pulmonary tuberculosis (SNPT) from smear-positive pulmonary tuberculosis (SPPT). METHODS: A total of 125 participants were included, 77 of whom had TB and 48 who didn't, and demographic, clinical, and laboratory data were collected, including cytokine levels and IGRA results. The TB patients were further divided into 2 subgroups: SNPT (n=42) and SPPT (n=35). RESULTS: Compared to non-TB, the TB group had lower BMI, higher WBC, neutrophils, monocytes, ESR and CRP (p<0.05). TB patients showed higher IL-2, IL-6, IFN-γ, IL-8 (p<0.001) and higher IGRA positivity (88.3% versus [vs.] 29.2%, p<0.001). Between SNPT and SPPT, moderate effect sizes were observed for IFN-α, IL-2, IL-10, IL-8 (Cohen's d 0.59-0.76), with lower IGRA positivity in SNPT (81.0% vs. 97.1%, p=0.015). ROC analysis indicated IFN-α, IL-2, IL-10, IL-8 had moderate accuracy for SNPT diagnosis (AUCs 0.668-0.734), and combining these improved accuracy (AUC 0.759, 80% sensitivity, 64.2% specificity). CONCLUSION: A multi-biomarker approach combining these cytokines demonstrates enhanced diagnostic accuracy for tuberculosis.

Modelling of tuberculosis dynamics incorporating indirect transmission of contaminated environment and infectivity of smear-negative individuals: A case study for Xinjiang, China.

Xinjiang has been one of the high incidence areas of pulmonary tuberculosis (PTB) in China. Besides being infected by direct contacting with active PTB individuals (direct infection), the susceptible would be infected because of the exposure to the environment contaminated by Mycobacterium tuberculosis (indirect infection). Active PTB individuals include not only the smear-positive PTB (PTB+) but also the smear-negative PTB (PTB-) who are infectious due to their ability to release tiny Mycobacterium tuberculosis particles even in the absence of visible Mycobacterium tuberculosis in sputum. By taking account of direct/indirect infection and the difference between PTB+ and PTB- individuals in transmission capability, a periodic dynamical PTB transmission model is proposed. The model is fitted to the newly monthly PTB+ and PTB- cases in Xinjiang from 2008 to 2017 by Markov Chain Monte Carlo algorithm. Moreover, global sensitivity analysis is constructed to address the uncertainty of some key parameters by using Latin hypercube sampling and partial rank correlation coefficient methods. Basic reproduction number R0 for PTB transmission in Xinjiang is estimated to be 2.447 (95% CrI:(1.203, 3.844)), indicating that PTB has been prevalent in Xinjiang over the study period. Our results suggest that reducing the direct/indirect transmission rates, early screening, isolating and treating the latent, PTB+ and PTB- individuals, and enhancing the clearance of Mycobacterium tuberculosis in the environment could more effectively control PTB transmission in Xinjiang. The model fits the reported PTB data well and achieves acceptable prediction accuracy. We believe that our model can provide heuristic support for controlling PTB transmission in Xinjiang.

Proteomic analyses of smear-positive/negative tuberculosis patients uncover differential antigen-presenting cell activation and lipid metabolism.

Background: Tuberculosis (TB) remains a major global health concern, ranking as the second most lethal infectious disease following COVID-19. Smear-Negative Pulmonary Tuberculosis (SNPT) and Smear-Positive Pulmonary Tuberculosis (SPPT) are two common types of pulmonary tuberculosis characterized by distinct bacterial loads. To date, the precise molecular mechanisms underlying the differences between SNPT and SPPT patients remain unclear. In this study, we aimed to utilize proteomics analysis for identifying specific protein signatures in the plasma of SPPT and SNPT patients and further elucidate the molecular mechanisms contributing to different disease pathogenesis. Methods: Plasma samples from 27 SPPT, 37 SNPT patients and 36 controls were collected and subjected to TMT-labeled quantitative proteomic analyses and targeted GC-MS-based lipidomic analysis. Ingenuity Pathway Analysis (IPA) was then performed to uncover enriched pathways and functionals of differentially expressed proteins. Results: Proteomic analysis uncovered differential protein expression profiles among the SPPT, SNPT, and Ctrl groups, demonstrating dysfunctional immune response and metabolism in both SPPT and SNPT patients. Both groups exhibited activated innate immune responses and inhibited fatty acid metabolism, but SPPT patients displayed stronger innate immune activation and lipid metabolic inhibition compared to SNPT patients. Notably, our analysis uncovered activated antigen-presenting cells (APCs) in SNPT patients but inhibited APCs in SPPT patients, suggesting their critical role in determining different bacterial loads/phenotypes in SNPT and SPPT. Furthermore, some specific proteins were detected to be involved in the APC activation/acquired immune response, providing some promising therapeutic targets for TB. Conclusion: Our study provides valuable insights into the differential molecular mechanisms underlying SNPT and SPPT, reveals the critical role of antigen-presenting cell activation in SNPT for effectively clearing the majority of Mtb in bodies, and shows the possibility of APC activation as a novel TB treatment strategy.

Analysis of the role of molecular diagnostic technology in improving the bacteriological diagnostic rate of tuberculosis / 中华传染病杂志

Objective:To analyze the relevant factors of bacteriological diagnosis rate in pulmonary tuberculosis in Zhejiang Province, and to provide basis for the control of tuberculosis.Methods:The results of etiology detection of pulmonary tuberculosis in Zhejiang Province from 2015 to 2020 were collected from the China Tuberculosis Information Management System. Positive detection of etiology of pulmonary tuberculosis cases was analyzed. Joinpoint regression model was constructed to evaluate the annual trend of the positive rate of etiology, and linear regression model was used to analyze the influence of new diagnostic technology on the positive detection rate of etiology in smear-negative pulmonary tuberculosis cases.Results:From 2015 to 2020, the positive rate of etiology of pulmonary tuberculosis in Zhejiang Province increased from 38.66%(10 588/27 385) to 64.12%(14 275/22 262), with an average annual growth rate of 8.80%. All of the 11 prefecture cities in Zhejiang Province showed an increasing trend of the positive rate of etiology. The average annual growth rates in Wenzhou City and Lishui City were 10.27% and 11.21%, respectively, and the positive rates of etiology in Jinhua City and Lishui City were 70.13%(2 007/2 862) and 73.34%(707/964) in 2020, respectively. From 2015 to 2020, smear-negative cases accounted for 61.66%(92 935/150 733) in Zhejiang Province, and the further detection rate by culture and molecular test increased from 0.13%(22/16 650) to 84.74%(11 384/13 434). The positive rate of bacteriological tests in smear-negative pulmonary tuberculosis patients increased from 0.04%(6/16 650) to 41.28%(5 546/13 434). If the culture and molecular detection rate increased to 100.00%, the linear regression model predicted positive rate of etiology could increase to 44.20%. Thus, the positive rate of etiology of pulmonary tuberculosis in Zhejiang Province would reach 66.00%. Up to 2020, 95.56%(86/90) and 92.22%(83/90) of tuberculosis designated hospitals were equipped with molecular and liquid diagnostic equipments, respectively, and the detection positive rates of molecular and liquid diagnostics in the etiology positive pulmonary tuberculosis cases were 71.24%(10 169/14 275) and 53.44%(7 629/14 275), respectively.Conclusions:The implementation and promotion of the new diagnostic techniques for tuberculosis, especially the molecular diagnostic techniques, could significantly improve the positive rate of etiology of pulmonary tuberculosis etiology. Methods and strategies of etiological diagnosis of tuberculosis should be paid more attention in prevention and control of tuberculosis.

Diagnostic efficacy of joint detection of Xpert MTBRIF, TB-RNA and TB-DNA in bronchoalveolar lavage fluid for smear-negative pulmonary tuberculosis / 中国热带医学

@#Abstract: Objective　To investigate the diagnostic value of joint detection of Mycobacterium tuberculosis rifampicin resistance gene (Xpert MTB/RIF), Mycobacterium tuberculosis ribonucleic acid (TB-RNA) and Mycobacterium tuberculosis deoxyribonucleic acid (TB-DNA) in bronchoalveolar lavage fluid for smear-negative pulmonary tuberculosis. Methods A total of 806 patients with suspected smear-negative pulmonary tuberculosis admitted to our hospital from May 2020 to July 2022 were selected, 506 patients diagnosed as bacterial negative pulmonary tuberculosis by clinical, X-ray and sputum samples were classified as bacterial negative pulmonary tuberculosis group, and the other 300 patients with non-tuberculous pulmonary disease were classified as non-tuberculous pulmonary disease group. XpertMTB/RIF, TB-RNA and TB-DNA in bronchoalveolar lavage fluid of all patients were detected. With clinical, X-ray and sputum specimen examination of mycobacterium tuberculosis as the gold standard, the diagnostic efficacy of alveolar lavage solution Xpert MTB/RIF, TB-RNA and TB-DNA alone and in combination was analyzed. Results The positive detection rates of Xpert MTB/RIF, TB-RNA and TB-DNA in bronchoalveolar lavage fluid of the smear-negative pulmonary tuberculosis group and the non-tuberculosis pulmonary disease group were 69.96% (354/506) and 2.67% (8/300), 61.46% (311/506) and 5.00% (15/300), and 63.64% (322/506) and 8.00% (24/300), respectively. The rates in the smear-negative pulmonary tuberculosis group were higher than those in the non-tuberculosis lung disease group, and the differences were statistically significant (χ2=342.005, 246.930, 235.687, P<0.01). Compared with the gold standard, the sensitivity, specificity, accuracy, positive predictive value and negative predictive value of Xpert MTB/RIF in the diagnosis of smear-negative pulmonary tuberculosis were 69.96%, 97.33%, 80.15%, 97.79% and 65.77%, respectively; those values of TB-RNA were 61.46%, 95.00%, 73.95%, 95.40% and 59.38%, respectively; those values of TB-DNA were 63.64%, 92.00%, 74.19%, 93.06% and 60.00%, respectively; those values of combined diagnosis with Xpert MTB/RIF, TB-RNA and TB-DNA were 61.26%, 100.00%, 75.68%, 100.00% and 60.48%, respectively; the specificity and positive predictive value of combined detection were higher than those of single detection (P<0.05). Conclusions The joint detection of Xpert MTB/RIF, TB-RNA and TB-DNA in bronchoalveolar lavage fluid can improve the diagnostic efficacy of smear-negative pulmonary tuberculosis and is worthy of clinical promotion and application.

Role of Gene Xpert in smear negative pulmonary tuberculosis.

BACKGROUND: Tuberculosis is a major health problem contributing to significant morbidity and mortality. Early diagnosis and treatment is the key for TB control. Sputum microscopy is a rapid and inexpensive test but due to low and variable sensitivity, many cases can be missed. Culture is considered to be the gold standard but is time consuming. Gene Xpert is a novel and rapid cartridge based nucleic acid amplification test (CBNAAT) that can be used for prompt diagnosis. AIM: To compare the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of Gene Xpert with culture in diagnosing tuberculosis in sputum smear negative patients. METHODS: The study is a prospective observational study conducted from December 2017 to January 2019 on 189 patients, who were sputum smear negative but had signs and symptoms suggestive of tuberculosis. Their respiratory samples were taken (either sputum or bronchoalveolar lavage) and sent for Gene Xpert. The results were compared with culture, which was taken as the gold standard, and diagnostic accuracy was assessed. RESULT: A total of 189 patients were included in the study. In 25 patients sputum was taken and in 164 patients BAL was taken (which included 22 patients in whom sputum Gene Xpert was negative but there was high clinical suspicion of tuberculosis). The sensitivity, specificity, PPV and NPV of Gene Xpert in diagnosing smear negative pulmonary tuberculosis was found to be 96.3%, 81.3%, 87.5% and 94.2% respectively. CONCLUSION: Gene Xpert can be used as a rapid diagnostic tool in patients who are sputum smear negative but have clinical features highly suggestive of tuberculosis. It additionally helps in detecting rifampicin resistance. But every Gene Xpert positive case does not necessarily mean an active disease, therefore, past history of tuberculosis along with radiological signs of disease activity are to be considered. In case of negative Gene Xpert but high clinico-radiological suspicion of TB, patients should be followed up on regular intervals, while awaiting their culture.

Effect of sputum quality and role of Xpert® MTB/ RIF assay for detection of smear-negative pulmonary tuberculosis in same-day diagnosis strategy in Addis Ababa, Ethiopia.

Background: There is limited information on the performance of the Xpert® MTB/RIF test for diagnosis of smear-negative pulmonary tuberculosis (SNPT) and rifampicin resistance (RR) in the same-day diagnosis approach. The effects of sputum quality and other factors affecting the Xpert performance are also under-investigated. Objective: This study aimed to determine the performance of the Xpert® MTB/RIF test for detection of SNPT and RR in the same-day diagnosis strategy and the effect of sputum quality and other factors on its performance. Methods: A cross-sectional study was conducted from August 2017 to January 2018 across 16 health facilities in Addis Ababa, Ethiopia. Two spot sputum samples were collected from 418 presumptive SNPT patients, tested with Xpert® MTB/RIF, then compared to tuberculosis culture. Additionally, culture isolates were tested for RR by BACTEC MGIT™ 960 drug susceptibility testing (DST) and MTBDRplus version 2. Results: The Xpert® MTB/RIF test detected 24 (5.7%) SNPT cases, with a sensitivity of 92.3% (75.9% - 97.9%) and specificity of 99.2% (97.8% - 99.7%) compared with tuberculosis culture. Xpert® MTB/RIF also detected three (11.58%) RR strains with 100.0% concordance with BACTEC MGIT™ 960 DST and MTBDRplus results. Three blood-stained SNPT samples were positive by Xpert (30.0%), which was 6.9 times higher compared to salivary sputum (odds ratio: 6.9, 95% confidence interval: 1.36-34.96, p = 0.020). Conclusion: The performance of the Xpert® MTB/RIF to detect SNPT and RR in same-day diagnosis is high. However, SNPT positivity varies among sputum qualities, and good sample collection is necessary for better test performance.

The Diagnostic Value of the Thermostatic Amplification of Ribonucleic Acid in Bronchoalveolar Lavage Fluid in Smear-Negative Pulmonary Tuberculosis.

Objective: This study aimed to determine the value of the simultaneous amplification and testing for Mycobacterium tuberculosis in bronchoalveolar lavage fluid (BALF) in the diagnosis of smear-negative pulmonary tuberculosis (PTB). Methods: A total of 316 patients were selected, of which 197 had smear-negative PTB (observation group), and 119 did not have TB (control group). Bronchoscopy was performed in both groups, and BALF samples were collected for acid-fast bacilli smears, simultaneous amplification/testing for TB (SAT-TB), and BACTEC MGIT 960 cultures. The sensitivity, specificity, positive predictive, and negative predictive values of SAT-TB in BALF for the diagnosis of negative TB were calculated. Results: The sensitivity of SAT-TB detection was 45.18%, which was significantly higher than smears and slightly lower than cultures. The specificity of SAT-TB was 99.16%, which differed slightly from the other two methods. The positive predictive value was 98.89%, which was not significantly different from the other two methods. The negative predictive value of SAT-TB was 58.91%, which was higher than smears and slightly lower than cultures. Conclusion: The very high specificity and negative prediction of SAT-TB in BALF means that the method has great application value for the rapid diagnosis of smear-negative PTB.

A new droplet digital PCR assay: improving detection of paucibacillary smear-negative pulmonary tuberculosis.

OBJECTIVES: Smear-negative pulmonary TB (PTB) is difficult to diagnose. Current diagnosis and treatment monitoring methods have inherent limitations. Droplet digital PCR (ddPCR) is a new technique with high sensitivity. This study presents a novel ddPCR for rapid and sensitive identification of Mycobacterium tuberculosis (MTB). METHODS: MTB DNA was detected in respiratory specimens from suspected PTB cases using ddPCR assay, which was directed at two different locations within IS6110. We, for the first time, evaluated the clinical diagnostic ability of this ddPCR for paucibacillary smear-negative PTB. RESULTS: A total of 605 PTB suspects were recruited, including 263 patients with confirmed PTB (84.03% from smear-negative PTB) and 342 without PTB. The sensitivity and specificity of IS6110 ddPCR were 61.22% (95% confidence interval (CI) 55.00-67.10%) and 95.03% (95% CI 92.20-97.10%) for total PTB and 57.92% (95% CI 51.10-64.50%) and 94.57% (95% CI 91.20-96.90%) for smear-negative PTB. ddPCR assay outperformed Xpert MTB/RIF (53.08% vs 28.46%, P = 0.020) in smear-negative PTB detection. Furthermore, effective anti-TB treatment was linked to significantly lower IS6110 copies detected by ddPCR. CONCLUSION: Herein, we developed and validated a highly sensitive and robust ddPCR assay for MTB quantification in respiratory specimens, which improves diagnosis and therapeutic effect evaluation of smear-negative PTB.

Effectiveness of Endobronchial Ultrasound-Guided Transbronchial Biopsy Combined With Tissue Culture for the Diagnosis of Sputum Smear-Negative Pulmonary Tuberculosis.

Background: Microorganisms of tuberculosis (TB) are frequently difficult to identify from the airway specimen; therefore, lung biopsy for further histologic and microbiologic study is required. Endobronchial ultrasound-guided transbronchial biopsy (EBUS-TBB) is used for the diagnosis of pulmonary malignancy, but is rarely in the TB population. The purpose of this study was to verify the effectiveness and safety of EBUS-TBB with histologic study and tissue culture in the diagnosis of sputum smear-negative pulmonary TB. Methods: Patients who underwent EBUS-TBB with histologic study and TB tissue culture for clinically suspected, but sputum smear-negative pulmonary TB from January 2016 to December 2018, were included. The accuracy of each diagnostic modality was calculated, respectively. Factors that might influence the positive rate of TB culture (washing fluid and tissue specimen) were also evaluated. Results: One hundred sixty-one patients who underwent EBUS-TBB for clinically suspected, but sputum smear-negative pulmonary TB, were enrolled, and 43 of them were finally diagnosed as having pulmonary TB. The sensitivity of washing fluid (a combination of smear, culture, and polymerase chain reaction for TB) and tissue specimen (a combination of pathology and tissue culture) via EBUS-TBB for TB diagnosis were 48.8 and 55.8%, respectively. The sensitivity for TB diagnosis would be elevated to 67.4% when both washing fluid and tissue specimens are used. The positive TB culture rate would not statistically increase with a combination of tissue specimens and washing fluid. Univariate analysis revealed that TB microorganisms would be more easily cultivated when lesions had an abscess or cavity on the computed tomography (CT) image (presence vs. absence; 62.5 vs. 26.3%, p = 0.022), heterogeneous echogenicity on the EBUS finding (heterogeneous vs. homogeneous; 93.3 vs. 21.4%, p = 0.001), or a necrotic pattern via histologic study (presence vs. absence; 70.6 vs. 30.8%, p = 0.013). Heterogeneous echogenicity in the EBUS finding was the independent predictor according to the results of multivariate analysis. None of our patients encountered major adverse events or received further intensive care after EBUS-TBB. Conclusion: Endobronchial ultrasound-guided transbronchial biopsy is safe and effective for use in diagnosing sputum smear-negative pulmonary TB. EBUS echoic feature is also a predictor of the positive TB culture rate in pulmonary TB. However, tissue culture via EBUS-TBB has little effect in improving the positive TB culture rate.

Assessment of CD27 expression on T-cells as a diagnostic and therapeutic tool for patients with smear-negative pulmonary tuberculosis.

BACKGROUND: There is a global focus on illness diagnosis in smear-negative and latent tuberculosis infectious populations (SN-TB and LTBI). CD27 has been suggested to play a direct role in active TB. Little is known about smear-negative individuals. Here, we tried to investigate whether it has a role in smear-negative populations. The expression of CD27 and MTB-specific CD27 in CD4+ T cells ("CD27-CD4+" and "CD27-IFN-γ+CD4+") was evaluated in MTB-unexposed controls (HC), TB contacts (TB-C) and SN-TB individuals by flow cytometry. The sensitivity, specificity and AUC (area under curve) of "CD27-IFN-γ+CD4+" cells to distinguish SN-TBs from HCs and TB-Cs were determined by receiver operating characteristic (ROC) curve analysis. The clinical index was selected from the clinical laboratory and evaluated for correlation with "CD27-IFN-γ+CD4+" cells by Spearman statistical analysis. RESULTS: We observed that the percentages of "CD27-IFN-γ+CD4+" cells were significantly increased in the SN-TB group compared with the HC and TB-C groups (AUC was 0.88, sensitivity was 82.14%, specificity was 80.00%, and P < 0.0001). The percentage of "CD27-IFN-γ+CD4+" cells was negatively correlated with WBC (white blood cell count) (r = - 0.3019, P = 0.0182) and positively correlated with IgE (immunoglobulin E) (r = 0.2805, P = 0.0362). Furthermore, "CD27-IFN-γ+CD4+" cells were significantly decreased, especially in the > 50 years group, after clinical treatment. CONCLUSION: The present results demonstrated that the percentage of "CD27-IFN-γ+CD4+" cells might be a conceivable molecular indicator in the diagnosis of SN-TB and was influenced by its outcome of therapy.

Comparison of the diagnostic efficacy of the CapitalBio Mycobacterium real-time polymerase chain reaction detection test and Xpert MTB/RIF in smear-negative pulmonary tuberculosis.

To compare the diagnostic efficacy of CapitalBio Mycobacterium real-time polymerase chain reaction (RT-PCR) detection test and the first-generation Xpert MTB/RIF in smear-negative pulmonary tuberculosis (PTB). In this retrospective study of smear-negative PTB, we reviewed patient medical records to determine the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and area under the curve (AUC) of Xpert MTB/RIF, CapitalBio Mycobacterium detection test, and the parallel test (positive result for either of the Xpert MTB/RIF and CapitalBio Mycobacterium detection tests) to evaluate their diagnostic accuracy against a composite reference standard. In total, 1553 patients were evaluated. The sensitivity, specificity, PPV, NPV, and AUC of Xpert MTB/RIF, CapitalBio Mycobacterium detection test, and the parallel test were 57.1%, 92.9%, 81.1%, 95.9%, and 0.75; 53.4%, 97.7%, 98.6%, 41.5%, and 0.76; and 66.2%, 90.8%, 95.5%, 47.7%, and 0.79, respectively. For the bronchoalveolar lavage fluid (BALF) specimens, these values for Xpert MTB/RIF, CapitalBio Mycobacterium detection test, and the parallel test were 68.8%, 97.7%, 99.2%, 43.9%, and 0.83; 61.7%, 97.7%, 99.1%, 38.9%, and 0.80; and 77.0%, 95.5%, 98.6%, 50.9%, and 0.86, respectively. CapitalBio Mycobacterium detection test had moderate accuracy for smear-negative PTB, similar to Xpert MTB/RIF. The parallel test improved the sensitivity. BALF significantly improved the sensitivity and diagnostic accuracy of the test. The maximum diagnostic accuracy for smear-negative PTB was obtained with the parallel test and BALF specimens. BALF was the most effective specimen for diagnosing smear-negative PTB.

Evaluation of GeneXpert MTB/RIF as a diagnostic tool in patients with sputum smear-negative TB in a high HIV burden region in Nigeria.

BACKGROUND: There are challenges in the diagnosis of TB in people with smear-negative pulmonary TB (SNPTB) in resource-limited settings. We evaluated the diagnostic usefulness of Xpert MTB/RIF compared with TB culture among SNPTB. METHODS: The study was a cross-sectional study among patients with SNPTB. The Xpert MTB/RIF tests and sputum culture (using Lowenstein-Jensen medium) were performed. Sensitivity and specificity were calculated. RESULTS: Of 150 patients studied, the sensitivity and specificity of GeneXpert MTB/RIF were 81.8 and 97.4%, respectively. CONCLUSION: The sensitivity and specificity of Xpert MTB/RIF assay was comparative with culture in SNPTB patients.

Evaluation of Xpert MTB/RIF Ultra performance for pulmonary tuberculosis (TB) diagnosis in a city with high TB incidence in Brazil.

INTRODUCTION: Since 2018, World Health Organization (WHO) recommended the Xpert MTB/RIF Ultra use for pulmonary and extrapulmonary TB diagnosis, and suggested that Xpert Ultra should be tested in various populations, with different geographical and epidemiological settings. METHODS: Cross-sectional study with prospective data collection. Outpatients aged >18 years with respiratory symptoms suggestive of pulmonary TB were invited to participate. Sensitivity, specificity, positive and negative predictive values of the test were calculated and compared with the traditional Xpert MTB/RIF. RESULTS: During the study period, 180 patients met the inclusion and were included in the analysis. Xpert MTB/RIF Ultra test was positive in 33 patients (18.3%), and RIF resistance was detected in 1 (3.1%) patient. Considering culture as the gold standard, the sensitivity, specificity, positive predictive value, and negative predictive value of Xpert MTB/RIF Ultra were 100.0% (95% CI 85.2-100.0), 93.6% (95% CI 88.6-96.9), 69.7% (95% CI 55.8-80.7), and 100.0% (95% CI 87.2-100.0), respectively. The area under the ROC curve was 0.97 for the Xpert MTB/RIF Ultra test (95% CI 0.93 to 0.99; p < 0.0001). There was no difference statistically significant between sensitivities and specificities of Xpert MTB/RIF and Xpert MTB/RIF Ultra (p > 0.05). CONCLUSIONS: This is the first study in Brazil to evaluate the accuracy of Xpert MTB/RIF Ultra in individuals with presumptive pulmonary TB. The test showed an excellent sensitivity and a high specificity, demonstrating that it is a useful tool for pulmonary TB diagnosis.

Infectiousness of patients with smear-negative pulmonary tuberculosis, assessed by Real-time Polymerase Chain Reaction, XpertⓇMTB/RIF.

Currently, pulmonary tuberculosis (TB) isolation recommendations are based on serial sputum smear microscopy. To assess infectiousness of smear-negative/GeneXpert-positive (Sm-/GXpert+) pulmonary TB, we evaluated 511 contacts of pulmonary TB patients attended at a teaching hospital in Spain (2010-2018). There were no statistically significant differences in rates of Mycobacterium tuberculosis infection (46.2% contacts of smear-positive and 34.6% contacts of Sm-/GXpert+ pulmonary TB patients, p = 0.112). Sm-/GXpert+ pulmonary TB poses a substantial risk of transmission of M. tuberculosis infection. Our results add evidence to support including Real-time Polymerase Chain Reaction (XpertⓇMTB/RIF) in the work-up diagnosis of suspected pulmonary TB cases to make decisions on air-borne isolation.

Treatment Outcomes of Tuberculosis at Asella Teaching Hospital, Ethiopia: Ten Years' Retrospective Aggregated Data.

BACKGROUND: Directly Observed Treatment Short-course (DOTS) has been one of the major strategies to combat the epidemic of tuberculosis (TB) globally. This study aimed to evaluate TB treatment outcomes between September 2004 and July 2014 under the DOTS program at one of the largest public hospitals in Ethiopia. METHODS: A retrospective data of TB patients registered at Asella Teaching Hospital between September 2004 and July 2014 were obtained from hospital registry. Treatment outcomes and types of TB cases were categorized according to the national TB control program guideline. Binomial and multinomial logistic regression models were used to analyze the association between treatment outcomes and potential predictor variables. RESULTS: A total of 1,755 TB patients' records were included in the study. Of these, 945 (53.8%) were male, 480 (27.4%) smear-positive TB, 287 (16.4%) HIV positive, and 1,549 (88.3%) new cases. Among 480 smear-positive pulmonary TB cases, 377 (78.5%) patients were cured, 21 (4.40) completed the treatment, 35 (7.3%) transferred out, 19 (4.0%) died, 24 (5.0%) defaulted, and 4 (0.8%) failure. Overall, 398 (82.9%) smear-positive pulmonary TB patients were successfully treated. For smear-negative TB (n = 641) and extrapulmonary TB cases (n = 634), 1,036 (81.3%) completed the treatment and demonstrated favorable response. Taking all TB types into account, 1,434 (81.7%) were considered as successfully treated. In the multivariate binary logistic model, patients in older age group (AOR = 0.386, 95% CI: 0.250-0.596) and retreatment cases (AOR = 0.422, 95% CI: 0.226-0.790) were less likely to be successfully treated compared to younger and new cases, respectively. In multinomial logistic regression, age increment by 1 year increased the risk of death and default of TB patients by 0.05 (adjusted ß = 0.05; 95% CI: 0.03, 0.06) and 0.02 (adjusted ß = 0.02; 95% CI: 0.01, 0.04). The odds of TB patients who died during treatment were higher among HIV-infected TB patients (adjusted ß = 2.65; 95% CI: 1.28, 5.50). CONCLUSION: The treatment success rate of TB patients was low as compared to the national target. TB control needs to be strengthened for the enhancement of treatment outcome.

Evaluation of the Xpert MTB/RIF assay for the diagnosis of smear-negative pulmonary and extrapulmonary tuberculosis in Madagascar.

OBJECTIVE: To evaluate the feasibility of the implementation of a commercial rapid molecular diagnostic test (Xpert MTB/RIF) for the routine diagnosis of smear-negative or extrapulmonary tuberculosis (TB) and its diagnostic accuracy, and to assess HIV prevalence in a real-life setting in Madagascar. This study was set in a tertiary care hospital in Madagascar. METHODS: A prospective cohort study was conducted of all consecutive cases with suspected smear-negative and/or extrapulmonary TB over a 2-year period. Cases were classified as proven, probable, or possible TB cases, or as having an alternative diagnosis. RESULTS: Of the 363 patients included, 183 (50.4%) had suspected smear-negative pulmonary TB and 180 (49.6%) had suspected extrapulmonary TB. For proven cases, the sensitivity, specificity, positive and negative predictive values of Xpert MTB/RIF were 82.4%, 98.8%, 98.3%, and 86.6%, respectively; for proven and probable cases grouped together, these values were 65%, 98.8%, 98.5%, and 64%, respectively. The diagnostic accuracy was slightly lower for extrapulmonary TB compared to smear-negative pulmonary TB. The prevalence of HIV infection was 12.1%, but almost half of these cases did not have TB (alternative diagnosis group). CONCLUSIONS: The implementation of a rapid diagnosis programme for TB in a resource-poor setting is feasible. The performance of the Xpert-MTB/RIF was remarkable in this difficult-to-diagnose population. HIV prevalence in this study was much higher than the prevalence reported in the general population in Madagascar, in patients with TB and patients with conditions other than TB.

Diagnostic value of enzyme-linked immunospot assay combined with bronchoalveolar lavage fluid tuberculous Xpert detection in smear negative pulmonary tuberculosis / 国际检验医学杂志

Objective To investigate the diagnostic value of enzyme-linked immunosorbent assay combined with bronchoalveolar lavage fluid tuberculosis Xpert detection in smear negative pulmonary tuberculosis. Methods From August 2015 to August 2016 ,68 cases of smear negative pulmonary tuberculosis ,admitted in the hospital ,were enrolled in the study.Enzyme-linked immunosorbent assay and bronchoalveolar lavage fluid tuberculosis Xpert detection were used in the study.The results of enzyme-linked immunosorbent assay and tuberculosi sXpert detection were compared with sputum culture results ,and their diagnostic values for smear negative pulmonary tuberculosis were analyzed.Results The clinical manifestations of pulmonary tuberculosis were mainly nocturnal sweating ,fever ,cough and expectoration.The results of X-ray and CT examinations showed that the lesions were mostly patchy or in cloudy opacity.The diagnostic accuracy of the combined ex-amination for different types of pulmonary tuberculosis was significantly higher than single detection of en-zyme-linked immunosorbent assay or tuberculosis Xpert detection ,and the difference was statistically signifi-cant (P＜ 0.05).The sensitivity of enzyme-linked immunosorbent assay was 88.46%,the specificity was 69.05%,and the accuracy was 76.47%;the sensitivity of tuberculosis Xpert detection was 80.77%,the speci-ficity was 52.38%,and the accuracy was 63.23%;the sensitivity of the combined detection was 92.30%,the specificity was 78.57%,and the accuracy was 83.82%;the sensitivity ,the specificity and the accuracy of the combined detection for diagnosis of smear negative pulmonary tuberculosis were significantly increased ,and the difference was statistically significant (P＜0.05).Conclusion The enzyme-linked immunosorbent assay combined with bronchoalveolar lavage fluid tuberculosis Xpert detection has important value in the diagnosis of smear negative pulmonary tuberculosis.It is a simple ,rapid and effective method of examination.

Diagnostic performance of automated liquid culture and molecular line probe assay in smear-negative pulmonary tuberculosis.

The diagnosis of smear-negative pulmonary tuberculosis (PTB) is particularly challenging, and automated liquid culture and molecular line probe assays (LPA) may prove particularly useful. The objective of our study was to evaluate the diagnostic potential of automated liquid culture (ALC) technology and commercial LPA in sputum smear-negative PTB suspects. Spot sputum samples were collected from 145 chest-symptomatic smear-negative patients and subjected to ALC, direct drug susceptibility test (DST) testing and LPA, as per manufacturers' instructions. A diagnostic yield of 26.2% was observed among sputum smear-negative TB suspects with 47.4% of the culture isolates being either INH- and/or rifampicin-resistant. Complete agreement was observed between the results of ALC assay and LPA except for two isolates which demonstrated sensitivity to INH and rifampicin at direct DST but were rifampicin-resistant in LPA. Two novel mutations were also detected among the multidrug isolates by LPA. In view of the diagnostic challenges associated with the diagnosis of TB in sputum smear-negative patients, our study demonstrates the applicability of ALC and LPA in establishing diagnostic evidence of TB.

Induced sputum versus bronchial washings in the diagnosis of sputum negative pulmonary tuberculosis.

INTRODUCTION: Tuberculosis (TB) is one of the most important public health problems worldwide. Detecting patients with active pulmonary TB (PT) is an important component of TB control programs. However, at times in patients even with a compatible clinical picture, sputum smears do not reveal acid-fast bacilli (AFB) and smear-negative PT remains a common problem. This study compares the results of induced sputum (IS) and bronchial washings (BWs) in detecting sputum negative PT. MATERIALS AND METHODS: A prospective study conducted from June 2014 to June 2015, comprising 120 patients fulfilling study criteria. Patients with respiratory symptoms and chest roentgenogram suspicious of PT with no previous history of antiTB treatment (ATT) and two spontaneous sputum smear samples negative for AFB were included in the study. Patients with active hemoptysis and sputum positive were excluded from the study. Sputum induction was done using 5-10 ml of 3% hypertonic saline through ultrasonic nebulizer taking safety precautions. All the patients underwent fiberoptic bronchoscopy after 6 h fasting on the same day. About 20 ml of normal saline instilled into the suspected pathology area and washings were taken with gentle suction. The sample processing and fluorescent staining for AFB were done in a designated microscopy laboratory. RESULTS: Of 120 smear-negative PT patients, IS smear examination detected AFB in 76 patients (63.3%) and AFB detected from BWs in 94 patients (78.5%). Smear positivity higher in cavitary and infiltrative lesions compared to consolidation and infrahilar pattern disease. CONCLUSIONS: Even though both IS and BWs procedures were valuable for the diagnosis of smear-negative TB, sputum induction with hypertonic saline should be the initial procedure of choice, which can be repeated twice/thrice in a day or 2 consecutive days. If the patient remains IS smear-negative and if the clinical probability of TB is high, starting ATT and closely monitoring patient and reserving bronchoscopy to those patients who do not improve and to exclude alternative diagnosis seems to be a practically useful approach.