Pulmonary Tuberculosis Suspects Research Articles

Establishment of cross-priming amplification for point-of-care detection of Mycobacterium tuberculosis and non-tuberculosis mycobacteria

ObjectiveTo simplify sputum sample preparation steps and achieve point-of-care testing (POCT) of Mycobacterium tuberculosis (MTB) and non-tuberculosis mycobacteria (NTM) using Cross-Priming Amplification (CPA) technology on portable devices, overcoming the challenges of existing nucleic acid detection technologies that cannot be widely promoted in grassroots settings in China. MethodsEvaluate the liquefying ability of high-concentration guanidine thiocyanate (GTC) for sputum and the effectiveness of MTB inactivation; establish a rapid detection system for MTB and NTM based on CPA technology using EasyNAT integrated detection tubes, with the left amplification zone specific to MTB CPA amplification and the right amplification zone specific to both MTB and NTM CPA amplification. Suspected pulmonary tuberculosis (PTB) patients or patients diagnosed as suspected NTM pulmonary infections specimens collected from the Second Hospital of Longyan, Fujian Province, from September 2022 to September 2023, acid-fast bacilli (AFB) smear, quantitative real-time PCR (RT-PCR) and CPA-POCT were performed. The kappa coefficients was used to evaluate the consistency between the RT-PCR and CPA-POCT. ResultsThe liquefaction effect of 6M GTC on sputum was equivalent to 4 % NaOH, and no MTB growth was observed in the Lowenstein-Jensen medium of sputum samples treated with 6M GTC incorporating the H37Rv strain. The newly established CPA-POCT method showed good agreement with RT-PCR with a positive compliance rate of 86.27 %, a negative compliance rate of 89.36 %, an overall compliance rate of 87.75 %, and a Kappa coefficients of 0.786 (P < 0.05). Conclusion6M GTC can liquefy sputum and render MTB non-viable, eliminating the need for Mycobacterium nucleic acid testing in BSL-2 laboratories; the newly established CPA method can rapidly and accurately distinguish MTB and NTM in the form of POCT, with simple and fast operation, suitable for promotion and application in grassroots medical institutions and remote rural areas.

Analysis of Risk Factors on the Performance of Tuberculosis Control Program Officers in the Working Area of the Lubuk Kambing Health Center, Jambi, Indonesia

Indonesia is ranked 2nd in the country with the highest burden of tuberculosis (TB). In Jambi, the detection rate for pulmonary TB cases is still low (19%), and at the Lubuk Kambing Health Center, it only reaches 53%. This study aims to analyze the factors associated with the low rate of TB case detection in the Lubuk Kambing Health Center working area. Cross-sectional research design with 65 respondents. Data analysis uses logistic regression. There is a relationship between level of knowledge, motivation, workload, training, length of service, availability of TCM (molecular rapid test) facilities, active screening of pulmonary TB suspects, honorarium, family support, and evaluation of TB prevention and control officers and TB cadres with low detection capabilities d TB in the Lubuk Kambing Health Center working area. Availability of facilities is the dominant factor related to the low number of TB cases in the Lubuk Kambing Health Center working area. Efforts to increase knowledge, motivation, training, length of service, active screening, honorarium, and family support, as well as providing TCM facilities and regular evaluations, need to be carried out to increase the TB case detection rate.

Evaluating Diagnostic Utility of geneXpert Ultra (Mycobacterium tuberculosis/Rifampicin), Microscopy and Liquid Culture to Isolate Mycobacterium tuberculosis and Nontuberculous Mycobacteria among Pulmonary Tuberculosis Suspects

CONTEXT: Nontuberculous mycobacteria (NTM) are posing major public health problems and have recently gained importance as they are being isolated from patients with pulmonary disorders. Most of the time, NTM are misinterpreted as tuberculosis (TB) and this misdiagnosis leads to treatment failure. Hence, this study aimed to identify NTMs isolated from suspected cases of pulmonary TB cases and was aimed to distinguish Mycobacterium TB (MTB) from NTM infections. AIMS: Our study aimed to compare microscopy grading of respiratory samples with the Ct values of GeneXpert Ultra (MTB/rifampicin [RIF]), to assess the diagnostic accuracy of microscopy, GeneXpert ultra (MTB/RIF), liquid culture, to compare GeneXpert ultra (MTB/RIF) results with microscopy with culture and clinical implications, importance of performing a rapid test for pulmonary TB and pulmonary NTM infections in suspected cases of adults. SETTINGS AND DESIGN: The study was conducted in the Mycobacteriology laboratory, Department of Microbiology, in Kasturba Hospital, Manipal. The study was a prospective, cross-sectional study, single center. SUBJECTS AND METHODS: A total of 452 respiratory samples obtained from April to July 2023 were included in the study. Smearpositive pulmonary TB cases were identified and subjected to amplification by GeneXpert ultra (MTB/RIF) and 84 samples were GeneXpert ultra (MTB/RIF) positive and RIF sensitive. Liquid culture by mycobacteria growth indicator tube (MGIT) 960 was performed and for positive tubes, TB Ag MPT64 was performed. The results were compared and analyzed with patients’ demographic information. Clinical and radiological data from the requisition forms were assessed. STATISTICAL ANALYSIS USED: IBM SPSS statistics software version 22 was used. Correlations between GeneXpert ultra (MTB/RIF) Ct values and smear status were calculated by polychoric correlation. Extended McNemar’s test was used to find the association between the variables. RESULTS: GeneXpert ultra (MTB/RIF) yielded a positivity rate of 22.2% compared to smear microscopy 17.2%. Liquid culture yielded a positivity rate of 20.3%. Ct value and smear grading yielded a positive correlation (ρ = 0.8681; P &lt; 0.05). Undetected cases of TB by GeneXpert ultra (MTB/RIF) were identified as positive under liquid culture by MGIT 960. TB Ag MPT64 was performed and yielded NTM and speciated as Mycobacterium abscessus complex by line probe assay. CONCLUSIONS: Our study states the need for identification and differentiation of MTB from NTM.

Xpert MTB/RIF Ultra Assay Using Stool: an Effective Solution for Bacilli Identification from Adult Pulmonary Tuberculosis Suspects without Expectorated Sputum.

This study evaluated the diagnostic performance of stool-based Xpert MTB/RIF Ultra assay (Xpert-Ultra, Cepheid, USA) against other tests using respiratory tract specimens (RTS) and stool for diagnosing adult pulmonary tuberculosis. A prospective study on patients with presumptive pulmonary tuberculosis was conducted in Beijing Chest Hospital from June to November 2021. The smear test, MGIT960 liquid culture, and Xpert MTB/RIF (Xpert, Cepheid, USA) were performed simultaneously on RTS, and smear, culture Xpert, and Xpert-Ultra were performed simultaneously using stool. Patients were grouped based on the outcomes of RTS examination and other tests. In total, 130 eligible patients were enrolled that included 96 pulmonary tuberculosis and 34 non-TB patients. The sensitivity of smear, culture, Xpert, and Xpert-Ultra using stool was 10.96%, 23.28%, 60.27%, and 79.45%, respectively. The specificities of Xpert and Xpert-Ultra using RTS and stool were all 100% (34/34). Notably, all five confirmed cases detected by bronchoalveolar lavage fluid (BALF) examination yielded Xpert-Ultra positive outcomes with the stool specimens. Xpert-Ultra assay on stool sample harbors comparable sensitivity with Xpert on RTS. Thus, the Xpert-Ultra testing on stool specimens could be a very promising and practical strategy to improve pulmonary tuberculosis (PTB) diagnosis, especially among patients who could not expectorate sputum. IMPORTANCE This study is aimed at assessing the value of Xpert MTB/RIF Ultra (Xpert-Ultra) in PTB on stool in adult in low HIV settings and Xpert-Ultra assay on stool sample harboring comparable sensitivity with Xpert MTB/RIF on respiratory tract specimens. Although the yield in stool samples by Xpert-Ultra is lower than RTS, it may be useful in detecting disease in presumptive TB patients who cannot expectorate sputum and are not open to BALF collection. In addition, Xpert-Ultra with a "trace call" on stool in adult was highly supportive of PTB.

On-Field Test of Tuberculosis Diagnosis through Exhaled Breath Analysis with a Gas Sensor Array

Tuberculosis (TB) is among the more frequent causes of death in many countries. For pulmonary TB, early diagnosis greatly increases the efficiency of therapies. Although highly sensitive tests based on nucleic acid amplification tests (NAATs) and loop-mediated isothermal amplification (TB-LAMP) are available, smear microscopy is still the most widespread diagnostics method in most low-middle-income countries, and the true positive rate of smear microscopy is lower than 65%. Thus, there is a need to increase the performance of low-cost diagnosis. For many years, the use of sensors to analyze the exhaled volatile organic compounds (VOCs) has been proposed as a promising alternative for the diagnosis of several diseases, including tuberculosis. In this paper, the diagnostic properties of an electronic nose (EN) based on sensor technology previously used to identify tuberculosis have been tested on-field in a Cameroon hospital. The EN analyzed the breath of a cohort of subjects including pulmonary TB patients (46), healthy controls (38), and TB suspects (16). Machine learning analysis of the sensor array data allows for the identification of the pulmonary TB group with respect to healthy controls with 88% accuracy, 90.8% sensitivity, 85.7% specificity, and 0.88 AUC. The model trained with TB and healthy controls maintains its performance when it is applied to symptomatic TB suspects with a negative TB-LAMP. These results encourage the investigation of electronic noses as an effective diagnostic method for future inclusion in clinical practice.

Development and clinical validation of Swaasa AI platform for screening and prioritization of pulmonary TB

Acoustic signal analysis has been employed in various medical devices. However, studies involving cough sound analysis to screen the potential pulmonary tuberculosis (PTB) suspects are very few. The main objective of this cross-sectional validation study was to develop and validate the Swaasa AI platform to screen and prioritize at risk patients for PTB based on the signature cough sound as well as symptomatic information provided by the subjects. The voluntary cough sound data was collected at Andhra Medical College-India. An Algorithm based on multimodal convolutional neural network architecture and feedforward artificial neural network (tabular features) was built and validated on a total of 567 subjects, comprising 278 positive and 289 negative PTB cases. The output from these two models was combined to detect the likely presence (positive cases) of PTB. In the clinical validation phase, the AI-model was found to be 86.82% accurate in detecting the likely presence of PTB with 90.36% sensitivity and 84.67% specificity. The pilot testing of model was conducted at a peripheral health care centre, RHC Simhachalam-India on 65 presumptive PTB cases. Out of which, 15 subjects truly turned out to be PTB positive with a positive predictive value of 75%. The validation results obtained from the model are quite encouraging. This platform has the potential to fulfil the unmet need of a cost-effective PTB screening method. It works remotely, presents instantaneous results, and does not require a highly trained operator. Therefore, it could be implemented in various inaccessible, resource-poor parts of the world.

Identification Of Nontuberculous Mycobacterium Isolates in Suspected Pulmonary Tuberculosis Patients

According to World Health Organization, in the global tuberculosis ranking Pakistan is in 5th position. Mycobacterium tuberculosis bacterium is responsible for this dreadful disease, but there are other nontuberculous mycobacteria species that could also be the possible cause of this disease. Scanty data is available on the incidence and distribution of species responsible for this infection. Local studies on non-tuberculous mycobacterium species would be of great support in targeted therapy. Methods: This study was designed to investigate the incidence and distribution of non-tuberculous mycobacteria-associated infection in pulmonary suspected tuberculosis patients. Sputum samples were processed for microscopy and culturing on Lowenstein–Jensen regardless of age and gender suspected TB patients. Positive cultures were then processed for detection of non tuberculous mycobacteria species using commercially available Geno Type Mycobacterium CM hybridization strips. Results: A total of 1560 sputum samples were tested for Mycobacteria by culturing, 215 were positive, 71 contaminated and 1274 were negative. All 215 culture positive isolates were exposed to Geno Type Mycobacterium CM kit revealed, 55 cultures as Non-tuberculous mycobacteria and 160 as Mycobacterium complex. Adults between aged 40 to 60 years and male were predominantly (61.81%) infected than females (38.18%). Conclusions: Scanty data is available about the contributions of non tuberculous mycobacteria to tuberculosis-like disease, and noteworthy geographical distribution, clinical and molecular epidemiology-related knowledge gaps exist in the areas with a high burden of disease caused by mycobacterium tuberculosis complex. Isolation of nontuberculous mycobacteria from clinical specimens should promptly be evaluated for their clinical significance.

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

ObjectivesSmear-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). MethodsMTB 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. ResultsA 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. ConclusionHerein, 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.

Diagnosis of Pulmonary Tuberculosis by Gastric Aspirate in Adults Who are Smear Negative and X Ray Positive Suspects of Pulmonary Tuberculosis and Additional Yield by Fiberoptic Bronchoscopy

Diagnosis of Pulmonary Tuberculosis by Gastric Aspirate in Adults Who are Smear Negative and X Ray Positive Suspects of Pulmonary Tuberculosis and Additional Yield by Fiberoptic Bronchoscopy

Diagnostic utility of chest computerized tomography in the diagnosis of recurrence among sputum scarce and sputum negative previously treated pulmonary tuberculosis suspects.

Objective:The objective was to study the sensitivity, specificity, and diagnostic accuracy of various computed tomography (CT) chest findings in diagnosing recurrence among pulmonary tuberculosis (PTB) suspects.Materials and Methods:A prospective observational study was conducted in a tertiary care hospital in New Delhi. A total of 130 suspects with a past history of treatment for PTB, who presented with any of the symptoms suggestive of recurrence were included. Sputum-positive, HIV-positive patients, pregnant females, and patients aged <18 years were excluded. Patients underwent CT chest followed by bronchoalveolar lavage (BAL).Results:A total of 62 patients were there in the final analysis. The median age of the patients with recurrent PTB was 27.5 years. Cough was the universal symptom in all these patients (>90%). Hemoptysis was the predominant symptom among patients with chronic pulmonary aspergillosis (66.6%). Necrotic mediastinal lymph nodes had good diagnostic accuracy of 88.71% with area under the curve of 0.806, P < 0.001 in diagnosing recurrent TB. BAL GeneXpert and mycobacteria growth indicator tube had good sensitivity (83.33% and 84.62%, respectively), specificity (100% for both), and excellent diagnostic accuracy (95.16% and 96.36%, respectively) for diagnosing recurrence in sputum negative and sputum scarce patient, (P < 0.001) when compared with composite reference standard. For culture-positive cases, BAL GeneXpert MTB/RIF had 100% sensitivity and 97.73% specificity in diagnosing recurrent PTB patients.Conclusion:The presence of mediastinal necrotic lymph node is the most accurate CT finding that can differentiate recurrent TB from post-TB sequelae. No other single chest CT scan finding had reliable diagnostic accuracy in comparison to microbiological tools in diagnosing recurrence among sputum negative or scarce previously treated PTB suspects.

Cost-Utility Analysis of Molecular Testing for Tuberculosis Diagnosis in Suspected Pulmonary Tuberculosis in Thailand.

PurposeGiven the lack of economic evaluation study of molecular testing in Thailand, this study aimed to evaluate the cost-utility of molecular testing algorithms including Xpert MTB/RIF and the loop-mediated isothermal amplification (TB-LAMP) in the general population suspected of having pulmonary TB based on a societal perspective.MethodsA hybrid decision tree Markov model using a 1-month cycle length was used to evaluate costs and outcomes of five TB diagnostic algorithms: 1) sputum smear microscopy (SSM) with culture and drug susceptibility testing (DST), 2) Xpert MTB/RIF add-on, 3) Xpert MTB/RIF initial, 4) TB-LAMP add-on, and 5) TB-LAMP initial during a lifetime period. All costs were calculated in 2021 Baht, and results were presented as an incremental cost-effectiveness ratio (ICER) for molecular testing compared with SSM with culture. One-way sensitivity and probability analyses were used to evaluate uncertainty input parameters.ResultsTB-LAMP was less expensive overall (6565 Baht) than Xpert MTB/RIF (7010 Baht) and SSM with culture (6845 Baht). Molecular testing was projected to improve quality adjusted life year (QALY) by 0.53 to 0.94 years. In comparison to SSM with culture and DST, providing an initial TB-LAMP test was the most preferred choice. Xpert MTB/RIF Initial had the lowest ICER (197 Baht per QALY gained), followed by TB-LAMP Add-on (993 Baht per QALY gained) and Xpert MTB/RIF Add-on (3940 Baht per QALY gained). One-way sensitivity analysis uncovered that sensitivity of TB-LAMP was greater than that of other parameters.ConclusionProviding molecular testing including Xpert MTB/RIF and TB-LAMP as either initial or add-on test for TB diagnosis was more cost-effective than SSM with culture and DST in the general population with suspected pulmonary TB in Thailand. Our study could provide useful evidence to policymakers advocating for inclusion of molecular testing in the universal health coverage benefit package in Thailand.

Results of the TCM Method of Pulmonary Tuberculosis Examination on Lung TB Suspects

Tuberculosis (TB) is an infectious disease caused by the bacterium Mycobacterium tuberculosis (MTB). Determinants of pulmonary TB disease include gender, and age. The Rapid Molecular Test Method (TCM) is a breakthrough TB program for Drug Resistant TB patients. The TCM method takes two hours to get the patient's diagnosis. TCM method for diagnosing TB and resistance to rifampin quickly and accurately. Tidar Magelang Hospital is one of the referral places for TCM examinations from various health facilities. The purpose of this study was to describe the results of the TCM method of pulmonary TB examination on pulmonary TB suspects at Tidar Magelang Hospital. This type of research is descriptive. The research data is secondary data obtained from Tidar Hospital Magelang. Based on age, namely early adolescence, late adolescence, early adulthood, late adulthood, early elderly, late elderly, and seniors, the results were sensitive rif 0.76%, 11.45%, 9, 54%, 7.25%, 5.73%, 8.78% and 3.82%. Negative results 1.15%, 1.91%, 6.87%, 7.25%, 7.63%, 14.89% and 12.98%. The rif results were sensitive to 27.1% males and 20.23% females. Negative results in 31.3% men and 21.37% women. The most sensitive rif results are in Magelang, followed by Magelang City, then East Jakarta Municipality, Banjarnegara and Purworejo. Negative results were found in Magelang, followed by Magelang City, then Wonosobo and East Waringin City.

Diagnostic Value of Bronchoalveolar Lavage Examination in Sputum Negative Patients for AFB in Suspected Pulmonary Tuberculosis

Background: Pulmonary tuberculosis (PTB) is one of the most common infections worldwide, more commonly among the developing countries like Bangladesh. So its early detection and prompt treatment was a challenge and the burden of diagnostic challenge was higher if the patients smear negative for Acid Fast Bacilli (AFB). Objective: Evaluate the diagnostic value of Bronchoalveolar lavage (BAL) for diagnosis of suspected Pulmonary Tuberculosis (PTB) whose sputum for AFB smear neagtive. Materials and Methods: A cross-sectional observational reserach was undertaken where 50 patients were included on the basis of specific inclusion and exclusion criteria. All patients who had negative smear for AFB but highly suspected for PTB underwent fibreoptic bronchoscopy to collect Bronchoalveolar lavage (BAL) fluid for diagnostic testing in the form of BAL for AFB and mycobacterial culture in Lowenstein Jensen medium. Results: The Male predominacy 29 (58%) was obserevd among the smear negative PTB patients. Clinically more than seventy percent (72%) presents with fever then cough with sputum and haemoptysis 62% and 32% respectively. Radiological cavitation 33 (66%) was the most common x-ray findings. After analysis of BAL for AFB about 31 (62%) patient found positive and on culture about mycobacterial growth found in 29 (58%) patients. Conclusion: Bronchoalveolar lavage had a superior diagnostic value in patients with smear negative suspected pulmonary tuberculosis. KYAMC Journal.2021;12(02): 84-87

Validitas Metode Real Time PCR GeneXpert pada Suspek TB Paru BTA Negatif di RSUD Dr. Doris Sylvanus

Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis. Indonesia is one of the developing countries with high TB patients in the world. The most common detection used for TB diagnosis is sputum smear examination. Smear negative pulmonary TB still have a risk of infection and can develop into active. The GeneXpert molecular examination is a rapid diagnosis of TB by the real-time PCR method. The purpose of this study was to assess the validity of GeneXpert in smear-negative pulmonary TB compared to Lowenstein Jensen's culture. The design of this diagnostic test study is a cross-sectional study. The study was conducted on 40 people with smear-negative pulmonary TB suspect patients in Dr. Doris Sylvanus Regional Hospital. Sputum examination was performed with GeneXpert and compared with Lowenstein Jensen culture. The results of GeneXpert validity for diagnosing smear-negative pulmonary TB suspect are sensitivity 81.8%, specificity 96.5%, positive predictive value 90%, negative predictive value 93.3%, and accuracy 92.5%. It was concluded that GeneXpert has sensitivity, specificity, positive predictive value, negative predictive value, and high accuracy as a diagnostic tool in smear-negative pulmonary TB suspects.

Spatial clustering and genetic diversity of Mycobacterium tuberculosis isolate among pulmonary tuberculosis suspected patients, Arsi Zone, Ethiopia

BackgroundTuberculosis remains a serious public health concern globally. The enormous social, economic, and health impacts of the diseases are attributed to the lack of updated data on the prevalence, geospatial distribution, population structures, and genotypic variants of the circulating M. tuberculosis.MethodsStructured questionnaire, mycobacterial culture, and standard 24-Mycobacterial Interspersed Repeated Units-Variable Number Tandem Repeats (MIRU-VNTR) were employed to collect sociodemographic characters, residence linked information, and genotype the isolates. The retrospective discrete Bernoulli model was used to identify the hot spot districts of sputum smear positivity, and Web-based Miru-VNTRPlus were used for the identification of lineages and sublineages.ResultsOut of 832 presumptive pulmonary tuberculosis (PTB) suspects, 119 (14.3%) were smear-positive. In the multivariate binary logistic model, PTB suspected patients in the age groups of 7–25 and 25–34 and those from rural residents were 4.53 (AOR = 4.53; 95% CI 2.25–9.13), 3.00 (AOR = 3.00; 95% CI 1.41–6.35) and 1.65 (AOR = 1.65; 95% CI 1.01–2.70) times at higher risk of turning smear-positive. Eleven (47.8%) districts of Arsi Zone were shown to have a high rate of clustering (RR = 2.27; 95% CI 1.62–3.2) of smear-positive PTB. Of 72 isolates queried for the lineage assignment, 59 (81.9%) were classified into the previously known lineages and 13 (18.1%) were not assigned to any known lineages. Overall, 42 (58.3%) belong to M. tuberculosis lineage 4 (Euro-American), 16 (22.2%) M. tuberculosis lineage 3 (Delhi/CAS), and 1 (1.4%) M. tuberculosis Lineage 1 (Indo-Oceanic/ East Africa Indian). Further classification to the sublineage indicates that the predominant lineage was Delhi/CAS comprising 16 (22.2%) isolates followed by 15 (20.8%) isolates belonging to Haarlem. The remaining isolates were distributed as 13 (18.1%) TUR, 6 (8.3%) LAM, 4 (5.5%) URAL, 4 (4.5%) NEW-1 and 1 (1.4%) EAI.ConclusionOur study showed higher smear-positive results among PTB suspected patients and remarkable spatial variation across districts of Arsi Zone in smear-positive PTB. This information together with the genotypic features could be used as input for the efforts of designing control strategies.

The Accuracy of Emergency Physicians' Suspicions of Active Pulmonary Tuberculosis.

Objective: To investigate factors associated with recognition and delayed isolation of pulmonary tuberculosis (PTB). Background: Precise identification of PTB in the emergency department (ED) remains challenging. Methods: Retrospectively reviewed PTB suspects admitted via the ED were divided into three groups based on the acid-fast bacilli culture report and whether they were isolated initially in the ED or general ward. Factors related to recognition and delayed isolation were statistically compared. Results: Only 24.94% (100/401) of PTB suspects were truly active PTB and 33.77% (51/151) of active PTB were unrecognized in the ED. Weight loss (p = 0.022), absence of dyspnea (p = 0.021), and left upper lobe field (p = 0.024) lesions on chest radiographs were related to truly active PTB. Malignancy (p = 0.015), chronic kidney disease (p = 0.047), absence of a history of PTB (p = 0.013), and lack of right upper lung (p ≤ 0.001) and left upper lung (p = 0.020) lesions were associated with PTB being missed in the ED. Conclusions: Weight loss, absence of dyspnea, and left upper lobe field lesions on chest radiographs were related to truly active PTB. Malignancy, chronic kidney disease, absence of a history of PTB, and absence of right and/or left upper lung lesions on chest radiography were associated with isolation delay.

Prevalence and speciation of non-tuberculous mycobacteria among pulmonary and extrapulmonary tuberculosis suspects in South India

Background and objectivesNon tuberculous mycobacteria (NTM) is an emerging opportunistic pathogen increasing globally and indistinguishable from tuberculosis (TB), which remains a challenge particularly in developing countries. This study aimed to identify the prevalence and diversity of NTM among both pulmonary TB (PTB) and extrpulmonary TB (EPTB) clinical isolates from south India. MethodologyA total of 7633 specimens from TB suspects (PTB, n = 4327 and EPTB, n = 3306) were collected during the study period (July 2018–March 2020) in a tertiary care hospital. The study specimens were subjected to Ziehl Neelsen (ZN) staining and Auramine phenol (AP) staining followed by Lowenstein–Jensen (LJ) and mycobacteria growth indicator tube (MGIT) culture. The MPT64 immunochromatographic test (ICT) was performed among mycobacterial cultures and ICT negative isolates were subjected to Line Probe Assay (LPA). In addition, 53 (PTB, 48 and EPTB, 5) NTM MGIT positive cultures were collected from Intermediate Reference Laboratory (IRL), Puducherry and subjected to LPA for speciation. ResultsOf the 7633 TB suspects, 0.6% were diagnosed as NTM diseases and 5.5% with Mycobacterium tuberculosis (MTBC). NTM infection was observed among 0.7% (31/4327) of PTB and 0.4% (14/3306) of EPTB. MTBC was detected among 6.1% (264/4327) of PTB and 4.6% (153/3306) of EPTB. Among 98 NTM cultures, 80.6% of isolates were recovered from PTB and 19.4% from EPTB specimens. Among pulmonary specimens, Mycobacterium intracellulare (26.6%), Mycobacterium abscessus (17.7%) and Mycobacterium kansasii (12.7%) were the most frequently detected species, while Mycobacterium intracellulare (21.1%), Mycobacterium scrofulaceum (15.8%) and Mycobacterium fortuitum (10.5%) were common in extrapulmonary specimens. ConclusionThe frequency of NTM infection among TB suspects was low at a South Indian tertiary care hospital. The most predominant NTM species isolated from both pulmonary and extrapulmonary specimens was M. intracellulare.

Diagnostic accuracy of BAL Gene Xpert compared to BAL AFB staining in Sputum negative Pulmonary Tuberculosis Suspects

Tuberculosis has stood the test of time over the millennia and still wreaks havoc on human life all over the world. We have studied the role of bronchoscopy in smear negative PTB suspects and have compared the results of BAL Gene Xpert with BAL AFB staining among the study population. We have also determined the microbiological profile in cases who are MTB negative. We retrospectively reviewed the respiratory samples (sputum and BAL) of 82 sputum negative PTB suspects from july 2018 – july 2019 for ZN stain and Gene Xpert. 25 cases were detected by Gene Xpert additionally to the 11 cases detected by BAL afb staining alone. Out of the 36 cases detected on gene Xpert 3(8%) were RIF resistant. These 5 samples which were positive on BAL AFB and negative on Gene Xpert,are suspected to be NON TB mycobacteria. Out of the remaining 41 samples, non TB culture results showed 8 Acinetobacter, 10 pseudomonas, 12 klebsiella, 2 e.coli,2 candida, 7 no growth on culture. According to our study, the bronchoscopic samples when subjected to Gene Xpert detect a higher number of cases which would go undetected otherwise compared to BAL AFB staining. Hence, bronchoscopy must be performed on such smear negative suspects and Gene Xpert could replace smear microscopy as initial diagnostic testing. It also helps in detecting first line drug resistance in addition.

Clinical metagenomic sequencing for diagnosis of pulmonary tuberculosis

The aim of this study is to investigate the clinical usefulness of metagenomic Next-generation sequencing (mNGS) on bronchoalveolar lavage fluid (BALF) samples to discriminate pulmonary tuberculosis (PTB) from Non-TB community-acquired pneumonia (CAP) in PTB suspects. We investigate the performance of mNGS on BALF samples from 110 PTB suspects, in comparison with conventional microbiological testing (solid media culture, acid-fast bacilli staining (AFS), Xpert) of BALF or sputum samples and final clinical diagnosis. We finally clinically diagnosed 48 cases of pulmonary tuberculosis patients and 62 cases of non-tuberculosis patients. Comparing to the final clinical diagnosis, mNGS produced a sensitivity of 47.92%, which was similar to that of Xpert (45.83%) and culture (46.81%), but much higher than that of AFS (29.17%) for TB diagnosis in BALF samples. Apart from detecting Mycobacterium tuberculosis, mNGS also identified mixed infections in PTB patients, including 3 fungal cases and 1 bacteria case. Meanwhile, mNGS efficiently identified 14 of 22 (63.63%) cases of non-tuberculous mycobacteria (NTM), 7 cases of fungi, 1 case of viral infection, and other common bacterial pathogens in Non-PTB group. Finally, mNGS identified 67.23% infection cases within 3 days, while the conventional methods identified 49.58% infection cases for over 90 days. Our data show that mNGS of BALF represents a potentially effective tool for the rapid diagnosis of PTB suspects.

Prevalence of Tuberculosis by Automated GeneXpert Rifampicin Assay and Associated Risk Factors Among Presumptive Pulmonary Tuberculosis Patients at Ataye District Hospital, North East Ethiopia.

BackgroundTuberculosis is a communicable disease that is a major cause of ill health, one of the top 10 causes of death worldwide, and the leading cause of death from a single infectious agent, even ranking above human immuno-deficiency virus (HIV/AIDS).ObjectiveTo assess the prevalence and associated risk factor of Mycobacterium tuberculosis among pulmonary tuberculosis (PTB) suspects attending at Ataye District Hospital from October 1, 2018, to February 30, 2019.MethodologyA facility-based cross-sectional study was conducted among 423 presumptive tuberculosis patients at Ataye District Hospital. Sputum was processed by MTB/RIF Xpert assay. Data were entered into EpiData 3.1 software and exported to SPSS version 20.0 (SPSS, Chicago, IL, USA) for analysis. Univariate and multivariate analyses were used to examine the relationship between the dependent and independent variables. Variables that show significance at P-value of 0.3 during univariate analysis were selected for multivariable analysis. A P-value of less than or equal to 0.05 was used to indicate statistical significance.ResultsOut of the total study participants, about 60% were male, and 39% were aged between 18 and 24 years. Of the total 423 PTB suspected patients, 38 (8.98%) of them were identified as having PTB by GeneXpert and 2/38 (5.3%) were resistant to rifampicin and 3/38 (7.89%) patients were co-infected with HIV. Participant age between 18 and 24 years and between 25 and 34 years, weight loss, chest pain, having contact history with confirmed PTB cases, utilization of congested transportation, and a history of imprisonment were significantly associated with the prevalence of PTB.ConclusionA considerable prevalence of PTB in the area was observed and the magnitude of MDR-TB was low. PTB is still a public health problem in Ethiopia and there is a need for collaborative prevention and control activities in the study area.