Comparison of sputum induction and bronchoscopy in diagnosis of sputum smear-negative pulmonary tuberculosis: a systemic review and meta-analysis

Thoracic Society of Australia and New Zealand position statement: The safe clinical use of sputum induction for bio-sampling of the lower airways in children and adults

Sputum induction is widely used in clinical settings for collection of biological samples from the lower airways. However, in recent years sputum induction has been associated with serious adverse events and even death. This position statement was commissioned by the Thoracic Society of Australia and New Zealand to address major adverse events of two deaths associated with sputum induction that have occurred in Australia in 2021, and outlines best practice for the safe use of sputum induction. The statement resulted from systematic literature searches by a multi-disciplinary group including respiratory physicians, nurses and physiotherapists (paediatric and adults focused). Consumers had input to an advanced draft of the position statement. The position statement covers indications for sputum induction, informed consent, scope of practice of personnel administering the procedure, infection control considerations, details about the sputum induction procedure, safety considerations and risk assessment in clinical settings.

Safety of a controlled human infection model of tuberculosis with aerosolised, live-attenuated Mycobacterium bovis BCG versus intradermal BCG in BCG-naive adults in the UK: a dose-escalation, randomised, controlled, phase 1 trial

BACKGROUND

Mycobacterium tuberculosis is the main causative agent of tuberculosis. BCG, the only licensed vaccine, provides inadequate protection against pulmonary tuberculosis. Controlled human infection models are useful tools for vaccine development. We aimed to determine a safe dose of aerosol-inhaled live-attenuated Mycobacterium bovis BCG as a surrogate for M tuberculosis infection, then compare the safety and tolerability of infection models established using aerosol-inhaled and intradermally administered BCG.

METHODS

This phase 1 controlled human infection trial was conducted at two clinical research facilities in the UK. Healthy, immunocompetent adults aged 18-50 years, who were both M tuberculosis-naive and BCG-naive and had no history of asthma or other respiratory diseases, were eligible for the trial. Participants were initially enrolled into group 1 (receiving the BCG Danish strain); the trial was subsequently paused because of a worldwide shortage of BCG Danish and, after protocol amendment, was restarted using the BCG Bulgaria strain (group 2). After a dose-escalation study, during which participants were sequentially allocated to receive either 1 × 103, 1 × 104, 1 × 105, 1 × 106, or 1 × 107 colony-forming units (CFU) of aerosol BCG, the maximum tolerated dose was selected for the randomised controlled trial. Participants in this trial were randomly assigned (9:12), by variable block randomisation and using sequentially numbered sealed envelopes, to receive aerosol BCG (1 × 107 CFU) and intradermal saline or intradermal BCG (1 × 106 CFU) and aerosol saline. Participants were masked to treatment allocation until day 14. The primary outcome was to compare the safety of a controlled human infection model based on aerosol-inhaled BCG versus one based on intradermally administered BCG, and the secondary outcome was to evaluate BCG recovery in the airways of participants who received aerosol BCG or skin biopsies of participants who received intradermal BCG. BCG was detected by culture and by PCR. The trial is registered at ClinicalTrials.gov, NCT02709278, and is complete.

FINDINGS

Participants were assessed for eligibility between April 7, 2016, and Sept 29, 2018. For group 1, 15 participants were screened, of whom 13 were enrolled and ten completed the study; for group 2, 60 were screened and 33 enrolled, all of whom completed the study. Doses up to 1 × 107 CFU aerosol-inhaled BCG were sufficiently well tolerated. No significant difference was observed in the frequency of adverse events between aerosol and intradermal groups (median percentage of solicited adverse events per participant, post-aerosol vs post-intradermal BCG: systemic 7% [IQR 2-11] vs 4% [1-13], p=0·62; respiratory 7% [1-19] vs 4% [1-9], p=0·56). More severe systemic adverse events occurred in the 2 weeks after aerosol BCG (15 [12%] of 122 reported systemic adverse events) than after intradermal BCG (one [1%] of 94; difference 11% [95% CI 5-17]; p=0·0013), but no difference was observed in the severity of respiratory adverse events (two [1%] of 144 vs zero [0%] of 97; 1% [-1 to 3]; p=0·52). All adverse events after aerosol BCG resolved spontaneously. One serious adverse event was reported-a participant in group 2 was admitted to hospital to receive analgesia for a pre-existing ovarian cyst, which was deemed unrelated to BCG infection. On day 14, BCG was cultured from bronchoalveolar lavage samples after aerosol infection and from skin biopsy samples after intradermal infection.

INTERPRETATION

This first-in-human aerosol BCG controlled human infection model was sufficiently well tolerated. Further work will evaluate the utility of this model in assessing vaccine efficacy and identifying potential correlates of protection.

FUNDING

Bill & Melinda Gates Foundation, Wellcome Trust, National Institute for Health Research Oxford Biomedical Research Centre, Thames Valley Clinical Research Network, and TBVAC2020.

How We Treat Drug-Susceptible Pulmonary Tuberculosis: A Practical Guide for Clinicians

Tuberculosis (TB) remains one of the leading causes of morbidity and mortality worldwide and pulmonary TB (PTB) is the main variant responsible for fueling transmission of the infection. Effective treatment of drug-susceptible (DS) TB is crucial to avoid the emergence of Mycobacterium tuberculosis-resistant strains. In this narrative review, through a fictional suggestive case of DS PTB, we guide the reader in a step-by-step commentary to provide an updated review of current evidence in the management of TB, from diagnosis to post-treatment follow-up. World Health Organization and Centre for Diseases Control (CDC) guidelines for TB, as well as the updated literature, were used to support this manuscript.

Performance of mNGS in bronchoalveolar lavage fluid for the diagnosis of invasive pulmonary aspergillosis in non-neutropenic patients

The diagnosis of invasive pulmonary aspergillosis (IPA) diseases in non-neutropenic patients remains challenging. It is essential to develop optimal non-invasive or minimally invasive detection methods for the rapid and reliable diagnosis of IPA. Metagenomic next-generation sequencing (mNGS) in bronchoalveolar lavage fluid (BALF) can be a valuable tool for identifying the microorganism. Our study aims to evaluate the performance of mNGS in BALF in suspected IPA patients and compare it with other detection tests, including serum/BALF galactomannan antigen (GM) and traditional microbiological tests (BALF fungal culture and smear and lung biopsy histopathology). Ninety-four patients with suspicion of IPA were finally enrolled in our study. Thirty-nine patients were diagnosed with IPA, and 55 patients were non-IPA. There was significance between the IPA and non-IPA groups, such as BALF GM (P < 0.001), history of glucocorticoid use (P = 0.004), and pulmonary comorbidities (P = 0.002), as well as no significance of the other demographic data including age, sex, BMI, history of cigarette, blood GM assay, T-SPOT.TB, and NEUT#/LYMPH#. The sensitivity of the BALF mNGS was 92.31%, which was higher than that of the traditional tests or the GM assays. The specificity of BALF mNGS was 92.73%, which was relatively similar to that of the traditional tests. The AUC of BALF mNGS was 0.925, which presented an excellent performance compared with other traditional tests or GM assays. Our study demonstrated the important role of BALF detection by the mNGS platform for pathogen identification in IPA patients with non-neutropenic states, which may provide an optimal way to diagnose suspected IPA disease.

Etiologic Investigation of Patients Diagnosed with Bacteriologically Unconfirmed Tuberculosis in Tanzania

Globally, half of patients with pulmonary tuberculosis (PTB) are diagnosed clinically without bacteriologic confirmation. In clinically diagnosed PTB patients, we assessed both the proportion in whom PTB could be bacteriologically confirmed by reference standard diagnostic tests and the prevalence of diseases that mimic PTB. We recruited adult patients beginning treatment of bacteriologically unconfirmed PTB in Moshi, Tanzania, in 2019. We performed mycobacterial smear, Xpert MTB/RIF Ultra, and mycobacterial culture, fungal culture, and bacterial culture on two induced sputum samples: fungal serology and computed tomography chest scans. We followed participants for 2 months after enrollment. We enrolled 36 (63%) of 57 patients with bacteriologically unconfirmed PTB. The median (interquartile range) age was 55 (44-67) years. Six (17%) were HIV infected. We bacteriologically confirmed PTB in 2 (6%). We identified pneumonia in 11 of 23 (48%), bronchiectasis in 8 of 23 (35%), interstitial lung disease in 5 of 23 (22%), pleural collections in 5 of 23 (22%), lung malignancy in 1 of 23 (4%), and chronic pulmonary aspergillosis in 1 of 35 (3%). After 2 months, 4 (11%) were dead, 21 (58%) had persistent symptoms, 6 (17%) had recovered, and 5 (14%) were uncontactable. PTB could be bacteriologically confirmed in few patients with clinically diagnosed PTB and clinical outcomes were poor, suggesting that many did not have the disease. We identified a high prevalence of diseases other than tuberculosis that might be responsible for symptoms.

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.

Stool specimen for diagnosis of pulmonary tuberculosis in adults: a systematic review

OBJECTIVE

To assess the diagnostic accuracy of stool specimens to diagnose pulmonary tuberculosis (PTB) in adults.

DESIGN

Systematic review.

DATA SOURCES

MEDLINE (Ovid), Embase (Ovid), Web of Science and the Cochrane database were searched from inception to 9 March 2023-10 March 2023 using a comprehensive search strategy; reference lists of selected articles and relevant review articles were manually searched.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Studies in English reporting diagnostic performance of stool specimens against respiratory specimens using mycobacterial culture or smear microscopy or Xpert assay to diagnose PTB in adults were eligible for this systematic review.

DATA EXTRACTION AND SYNTHESIS

Two reviewers independently screened the retrieved citations and extracted data. The risk of bias and applicability of results were assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. Narrative data synthesis was performed.

RESULTS

A total of 1658 citations were screened, and 28 full-text articles were assessed. Nine studies met the inclusion criteria. The reported sensitivity and specificity of stool culture varied between 21.4% and 63.9%, and 61.5% and 100%, respectively. In stool smear microscopy, sensitivities and specificities ranged from 12.1% to 53.9%, and from 79.5% to 100%, respectively. The reported sensitivities of PCR assays, including Xpert assays, ranged from 69.7% to 100%, with specificities ranging from 69.8% to 100%. Most of the studies had a low risk of bias and a low applicability concern in all domains.

CONCLUSION

This systematic review could not conclude on the diagnostic accuracy of stool specimens for PTB diagnosis in adults. Further studies are required to evaluate the accuracy of stool specimens in adults to enable meta-analyses in updates of this review as well as other systematic reviews.

PROSPERO REGISTRATION NUMBER

CRD42021245203.

Bronchial Washing Using a Thin Versus a Thick Bronchoscope to Diagnose Pulmonary Tuberculosis: A Randomized Trial

BACKGROUND

This study was performed to evaluate the efficacy of using a thin bronchoscope for the diagnosis of pulmonary tuberculosis (PTB).

METHODS

Between March 2019 and November 2021, we prospectively enrolled participants with suspected PTB whose sputum acid-fast bacilli (AFB) smear and tuberculosis (TB) polymerase chain reaction (PCR) tests were negative or who could not produce self-expectorated sputum. Participants were randomized to a control group (bronchial washing [BW] using a 5.9-mm conventional bronchoscope guided by chest computed tomography) or an investigational group (BW using a 4.0-mm thin bronchoscope under virtual bronchoscopic navigation guidance). The primary outcome was detection of TB in BW fluid, defined as a positive result in the Xpert MTB/RIF assay. The secondary outcomes included AFB smear and Mycobacterium tuberculosis culture positivity, time to treatment initiation, and bronchoscopy-related complications.

RESULTS

In total, 85 participants were included in the final analysis (43 in the control group and 42 in the investigational group). Twenty-three and 29, respectively, were finally diagnosed with PTB. The TB detection rate in BW fluid was higher in the investigational group (72.4% vs 43.5%, P = .035). Mycobacterium tuberculosis culture positivity was also higher in the investigational group (79.3% vs 52.2%, P = .038). No participants required premature bronchoscopy termination because of complications. Of the participants with PTB, the time to treatment initiation was shorter in the investigational group (median, 2.0 days vs 4.0 days, P = .001).

CONCLUSIONS

BW using a thin bronchoscope increases the TB detection rate in patients with PTB compared to conventional bronchoscopy. Clinical Trials Registration.ȃNCT03802812.

Hospital Practices for Respiratory Isolation for Patients With Suspected Tuberculosis and Potential Application of Prediction Models

Hospitalized persons with suspected pulmonary tuberculosis (PTB) are placed in airborne isolation to prevent nosocomial infection, as recommended by the Centers for Disease Control and Prevention (CDC). There is significant evidence that clinicians overuse this resource due to an abundance of caution when confronted with a patient with possible PTB. Many researchers have developed predictive tools based on clinical and radiographic data to assist clinicians in deciding which patients to place in respiratory isolation. We assessed the isolation practices for an urban hospital serving a large immigrant population and then retrospectively applied seven previously derived prediction models of isolation of PTB to our population. Our current clinical practice results in 76% of patients with PTB being placed in isolation on admission. However, 208 patients without PTB were placed in isolation unnecessarily for a total of 584 days. Four models had sensitivities greater than 90%, and two models had sensitivities of 100%. The use of these models would have potentially saved more than 150 days of patient isolation per year.

A 22-Year-Old Man Coughs Blood

A 22-Year-Old Man Coughs BloodA 22-year-old man sought evaluation after coughing up foul-smelling, brown sputum mixed with bright-red blood. Symptoms were preceded by chest pain in the left parasternal region that was worse on deep inspiration. Using questions, physical examination, and testing, an illness script for the presentation emerges. The differential is refined until a final diagnosis is made.

Efficacy and Safety of Adjunctive Recombinant Human Interleukin-2 for Patients with Pulmonary Tuberculosis: A Meta-Analysis

Background. The results of previous clinical trials evaluating the efficacy and safety of recombinant human interleukin-2 (rhuIL-2) for adult patients with pulmonary tuberculosis showed inconsistent results. Accordingly, a comprehensive systematic review and meta-analysis was performed. Methods. Relevant randomized controlled trials (RCTs) were retrieved by searching the PubMed, Embase, Cochrane’s Library, Web of Science, Wanfang, and CNKI databases. A random-effects model was used to combine the results. Results. 18 RCTs with 2630 patients were included in this meta-analysis. Pooled results showed that adjunctive rhuIL-2 significantly increased the odds of sputum culture conversion to negative (risk ratio [RR]: 1.27, 95% CI: 1.09 to 1.47, $p=0.002$ , I2 = 80%), sputum smear conversion to negative (RR: 1.35, 95% CI: 1.17 to 1.57, $p<0.001$ , I2 = 83%), radiographic focus absorption (RR: 1.17, 95% CI: 1.06 to 1.30, $p=0.002$ , I2 = 72), and cavity closure (RR: 1.24, 95% CI: 1.09 to 1.40, $p<0.001$ , I2 = 23). The use of rhuIL-2 was not related to any severe adverse events which led to discontinuation of the treatment. Results showed that rhuIL-2 was related to an increased risk of fever (RR: 2.46, 95% CI: 1.29 to 4.70, $p=0.006$ , I2 = 0%). The incidence of other adverse events, such as musculoskeletal pain, hepatic injury, and renal toxicity, was not significantly different between groups ( $p$ all >0.05). Conclusions. rhuIL-2 is an effective adjunctive immunotherapy for patients with pulmonary tuberculosis.

Clinical standards for drug-susceptible pulmonary TB

BACKGROUND: The aim of these clinical standards is to provide guidance on 'best practice´ for diagnosis, treatment and management of drug-susceptible pulmonary TB (PTB).METHODS: A panel of 54 global experts in the field of TB care, public health, microbiology, and pharmacology were identified; 46 participated in a Delphi process. A 5-point Likert scale was used to score draft standards. The final document represents the broad consensus and was approved by all 46 participants.RESULTS: Seven clinical standards were defined: Standard 1, all patients (adult or child) who have symptoms and signs compatible with PTB should undergo investigations to reach a diagnosis; Standard 2, adequate bacteriological tests should be conducted to exclude drug-resistant TB; Standard 3, an appropriate regimen recommended by WHO and national guidelines for the treatment of PTB should be identified; Standard 4, health education and counselling should be provided for each patient starting treatment; Standard 5, treatment monitoring should be conducted to assess adherence, follow patient progress, identify and manage adverse events, and detect development of resistance; Standard 6, a recommended series of patient examinations should be performed at the end of treatment; Standard 7, necessary public health actions should be conducted for each patient. We also identified priorities for future research into PTB.CONCLUSION: These consensus-based clinical standards will help to improve patient care by guiding clinicians and programme managers in planning and implementation of locally appropriate measures for optimal person-centred treatment for PTB.

Additional Usefulness of Bronchoscopy in Patients with Initial Microbiologically Negative Pulmonary Tuberculosis: A Retrospective Analysis of a Korean Nationwide Prospective Cohort Study

Purpose

Bronchoscopy is widely used for microbiological diagnosis of patients with minimal sputum production. However, the usefulness of bronchoscopy in patient groups who benefit from subsequent microbiological confirmation has not been established.

Patients and Methods

We retrospectively analyzed Korean tuberculosis (TB) cohort data from September 2018 to October 2019 to evaluate the usefulness of bronchoscopy in patients with microbiologically negative pulmonary TB (based on initial sputum polymerase chain reaction and culture results). The primary outcome was the proportion of microbiological diagnoses made after bronchoscopy. Secondary outcomes were the predictors of microbiological confirmation and the percentage of additional resistance detection after bronchoscopy.

Results

A total of 5194 patients were diagnosed with pulmonary TB, 937 of whom were microbiologically negative for pulmonary TB based on the initial sputum findings. Of these, 319 patients underwent bronchoscopy, and further microbiological confirmation was achieved in 157 (49.1%) patients. The predictors of microbiological confirmation after bronchoscopy were age >65 years, female sex, and low body mass index (BMI). The rate of additional resistance detection was 10.5% (multidrug resistant/rifampin-resistant 3.8%; isoniazid-resistant 5.7%).

Conclusion

Bronchoscopy can be used for the detection of resistant pathogens. Bronchoscopy should be considered for microbiologically negative pulmonary TB in women aged >65 years and with low BMI for subsequent microbiological confirmation.

Diagnostic value of bronchoscopy in sputum-negative pulmonary tuberculosis patients and its correlation with clinicoradiological features

CONTEXT:

Tuberculosis (TB) remains endemic in Saudi Arabia. Little local data have been reported on bronchoscopic evaluation of sputum-negative pulmonary TB patients, which poses a significant diagnostic and therapeutic challenge.

AIMS:

To determine the diagnostic value of bronchoscopy and bronchoalveolar lavage (BAL) and its correlation with clinical and radiological features in sputum-negative, culture-confirmed pulmonary TB patients.

METHODS:

We performed a retrospective analysis of patients with definite or probable pulmonary TB with overall negative (smear and/or polymerase chain reaction [PCR]) or scanty sputum that had undergone bronchoscopy with BAL over a period of 5 years. Patients’ symptoms, radiological features, lung lobe lavaged, BAL acid-fast bacilli (AFB) stain, Mycobacterium TB (MTB)-PCR, and mycobacterial cultures were analyzed. Mycobacterial cultures (either sputum or BAL) were used as a reference standard.

RESULTS:

Out of 154 patients, 49 (32%) were overall sputum negative and underwent a diagnostic bronchoscopy. Dry cough and fever were the most common symptoms. Uncontrolled diabetes mellitus was the most frequent comorbidity identified in 15 (31%) patients. Fifty-nine percent of the patients had diffuse lung infiltrates, with consolidation being the most common abnormality (41%), followed by cavitation (39%). Right upper lobe was the most frequent lung lobe lavaged (31%), while transbronchial lung biopsies (TBLB) were obtained in 21 (43%). BAL mycobacterial culture and MTB PCR were positive in 35 (71%) and 23 (47%) patients, respectively. Combined BAL MTB PCR and TBLB provided rapid diagnosis in 28 (57%) patients.

CONCLUSIONS:

An overall diagnostic yield of 90% was achieved with combined use of BAL MTB PCR, culture, and histopathology. Upper lobe lavage and presence of cavities on chest imaging had a higher diagnostic yield.

Diagnostic Accuracy of Metagenomic Next-Generation Sequencing in Sputum-Scarce or Smear-Negative Cases with Suspected Pulmonary Tuberculosis

Objective

To investigate the diagnostic accuracy of metagenomic next-generation sequencing (mNGS) in bronchoalveolar lavage fluid (BALF) samples or lung biopsy specimens from which suspected pulmonary tuberculosis (PTB) patients have no sputum or negative smear.

Materials and Methods

Sputum-scarce or smear-negative cases with suspected PTB (n = 107) were analyzed from January 2018 to June 2020. We collected BALF or lung tissue biopsy samples with these cases of suspected TB during hospitalization. The diagnostic accuracy of mNGS for these samples was compared with those of conventional tests or the T-SPOT.TB assay.

Results

46 cases of PTB patients and 61 cases of non-PTB patients were finally enrolled and analyzed. mNGS exhibited a sensitivity of 89.13%, which was higher than conventional tests (67.39%) but equivalent to those of the T-SPOT.TB assay alone (76.09%) or T-SPOT.TB assay in combination with conventional tests (91.30%). The specificity of mNGS was 98.36%, similar to conventional tests (95.08%) but significantly higher than those of the T-SPOT.TB assay alone (65.57%) or the T-SPOT.TB assay in combination with conventional tests (63.93%). There was no significant difference in the diagnostic accuracy of mNGS in BALF samples and lung biopsy tissue specimens.

Conclusion

Our findings demonstrate that mNGS could offer improved detection of Mycobacterium tuberculosis in BALF or lung tissue biopsy samples in sputum-scarce or smear-negative cases with suspected PTB.

Stool specimen for diagnosis of pulmonary tuberculosis in adults: protocol for a systematic review and meta-analysis

INTRODUCTION

Tuberculosis (TB) continues to be a significant health burden, most commonly affecting the lungs and referred to as pulmonary TB (PTB). Diagnostic techniques of PTB primarily rely on expectorated sputum samples. However, the diagnostic yields are often hindered due to insufficient volume and quality of the sputum specimens. Moreover, some individuals are unable to provide sputum samples due to scanty sputum production or difficulty in coughing up and require an invasive procedure to obtain a respiratory sample, such as bronchoscopic or gastric aspiration. Thus, challenges in the acquisition of respiratory specimens warrant an alternate specimen. Therefore, this systematic review aims to evaluate the diagnostic accuracy of a stool specimen for the diagnosis of PTB in adults.

METHODS AND ANALYSIS

We will search MEDLINE (Ovid), Embase (Ovid), Web of Science and Cochrane database from inception to April 2021 using a comprehensive search strategy. Two reviewers will independently perform screening, data extraction and quality assessment. The risk of bias assessment and applicability of results of eligible studies will be performed using the Quality of Diagnostic Accuracy Studies-2 tool. Bivariate random-effects models will be performed to calculate pooled sensitivity, specificity, positive likelihood ratio and negative likelihood ratio and diagnostic odds ratio along with 95% CI of stool specimen for each reported diagnostic method against any of the reference standard test (ie, mycobacterial culture or smear microscopy or Xpert assay using respiratory specimens). Heterogeneity between studies will be assessed by I² statistics and Q statistic of the χ² test.

ETHICS AND DISSEMINATION

The results will be disseminated through publishing in a peer-reviewed medical journal and public presentations in relevant national and international conferences. As this is a systematic review of publicly available data, ethics approval is not required.

PROSPERO REGISTRATION NUMBER

CRD42021245203.