Thorax

Background High-risk subgroups among household contacts of persons with tuberculosis (TB) might benefit from additional interventions. However, the significance of an abnormal baseline chest radiograph (CXR) suggestive of TB, despite negative sputum microbiology, is uncertain. Methods Adults ([≥]18 years) with recent household TB exposure were enrolled at three South African sites (April 2021-September 2022). All participants underwent symptom screening, CXR, and sputum Xpert Ultra and MGIT culture. Pulmonary TB diagnosis was microbiologically-confirmed. Participants without prevalent TB were followed for symptomatic incident TB through 12 months. Multivariable logistic regression identified factors associated with abnormal CXR suggestive of TB. Poisson regression estimated adjusted incidence rate ratios (aIRR) with 95% confidence intervals (95%CI). Results Baseline CXR were available for 795/846 (94.0%) participants without prevalent TB and were abnormal in 157/795 (19.7%); associated with older age (adjusted odds ratio, aOR=1.04, 95%CI 1.02-1.05); prior TB (aOR=6.39, 95%CI 4.18-9.78); and current smoking (aOR=1.61, 95%CI 1.00-2.62). Symptomatic incident TB developed in 8/795 (1.0%) participants, including 7/8 (87.5%) who were asymptomatic and 4/8 (50.0%) with abnormal CXR at baseline. TB incidence was higher in those with abnormal versus normal CXR (aIRR=4.11, 95%CI 1.29-13.09), but after median 12.1 (IQR 11.1-13.1) months follow-up, 153/157 (97.5%) had not progressed to incident TB. Conclusions Adult household contacts with CXR abnormalities, but without prevalent TB, had a four-fold higher incidence of TB within one year, compared to those with normal CXR. This additional risk warrants targeted preventive treatment and extended surveillance, but since most remained TB-free, therapeutic TB treatment is not justified.

BackgroundSocial deprivation impacts chronic disease and acute admission outcomes. In interstitial lung disease (ILD), prior British Thoracic Society registry data for idiopathic pulmonary fibrosis has shown high deprivation was associated with poorer long-term outcomes. However, its impact on acute admissions in ILD is not known. MethodsWe undertook a multicentre, retrospective study of ILD-related admissions between 1st January 2017 and 31st December 2019 across 11 hospitals in the North West of England, utilising available real-world data. We determined social deprivation geographically by the 2019 English Indices of Deprivation deciles. The primary outcome was 90-day all-cause mortality. Results999 admissions met the inclusion criteria. 327/999 (32.7%) of admissions came from individuals geographically in the most deprived 20%. Across 999 admissions, in unadjusted survival analysis we observed a non-linear relationship between deprivation and 90-day all-cause mortality. In complete case multivariate modelling, deprivation demonstrated borderline significant association with all-cause mortality (HR 1.038, 95% CI 1.00 - 1.077, p = 0.050). However, this effect was lost in pooled analysis using multiple imputation (HR 1.001, 95% CI 0.971 - 1.033, p = 0.928). Male sex and pre-admission long-term oxygen were consistently associated with increased 90-day all-cause mortality across both models. Lower TLCO values were significantly associated with increased 90-day mortality in pooled analysis. ConclusionWe observe a high burden of acute ILD-related hospital admission amongst the most deprived 20%, suggesting geographical deprivation may impact acute healthcare seeking behaviours. Once admitted, the impact of deprivation appears more complex and multifactorial. Further studies which assess geographical and individual-level deprivation are needed to validate our findings. Key Messages What is already known on the topic?The British Thoracic Society idiopathic pulmonary fibrosis registry has previously demonstrated that higher social deprivation is associated with worse long-term outcomes. In other respiratory diseases, social deprivation impacts acute admission patterns and outcomes. What this study addsTo the best of our knowledge, this is the first study examining the relationship between social deprivation and acute ILD-related admission outcomes. This study demonstrates high acute admission burden from the geographically most deprived 20%. Once admitted, the association between geographical social deprivation and mortality outcomes appears complex and multifactorial in our modelling. How this may affect research, practice or policyThis study highlights the acute admission burden from highly deprived communities and the need for additional research to further understand the individual-level and geographical-level deprivation patients with ILD experience. We suggest the need for community outreach to build trust with deprived communities, alongside increasing awareness amongst patients, caregivers and primary care physicians in such communities. Deprivation must remain an important consideration in any new service or intervention to prevent worsening of health inequalities.

BackgroundThe World Health Organisation (WHO) recommends digital chest radiography (dCXR) with computer-aided detection (CAD) for tuberculosis (TB) screening of individuals >15 years of age. MethodologyAdults ([≥]18 years) were enrolled (March 2021-December 2022) in South Africa into a community-based Screening Cohort (household contacts) and a facility-based Triage Cohort (symptomatic clinic attendees). Microbiologically-confirmed pulmonary TB required positive sputum culture and/or Xpert Ultra. Asymptomatic TB was diagnosed in participants without TB symptoms. dCXR were read by blinded human readers and qXR CAD (0.5 threshold; Qure.AI, India). ResultsdCXR from 1,353 participants (886 Screening Cohort; 467 Triage Cohort) were analysed. Microbiologically-confirmed TB occurred in 48 (5.4%) Screening Cohort [9 symptomatic (19%) and 39 asymptomatic (81%)]; and 116 (24.8%) Triage Cohort (all symptomatic) participants. dCXR sensitivity (human readers) for asymptomatic TB in the Screening Cohort was 56.4%, vs. 72.4% for symptomatic TB in the Triage Cohort (difference -16%; 95%CI -2.9 to -29.1); with specificities 94.1% and 81.2%, respectively. Corresponding qXR CAD sensitivities were 69.2% vs. 83.6% (difference -14.4%; 95%CI -26 to -2.8), with specificities 89.3% and 73.5%, respectively. The difference in dCXR sensitivity and specificity for asymptomatic TB between qXR CAD and human readers was 12.8% (95%CI -0.48 to 26.1) and -4.8% (95%CI -12.4 to 28.2), respectively. ConclusionSensitivity of community-based dCXR screening for microbiologically-confirmed asymptomatic TB among household contacts was lower than for facility-based triage of symptomatic TB, but approached 70% with CAD. Neither human reader nor qXR CAD evaluation met WHO targets for a TB screening test (90% sensitivity; 80% specificity). Research in contextO_ST_ABSEvidence before this studyC_ST_ABSThe World Health Organisation (WHO) recommends digital chest radiography (dCXR) with computer-aided detection (CAD) for tuberculosis (TB) screening of individuals >15 years of age, based on data from prevalence surveys and facility-based studies. Performance data for community-based screening of asymptomatic TB are lacking. We searched PubMed for literature published in English between January 1, 2000, and November 1, 2025, for community-based, active case-finding studies of adolescents and adults aged 15 years and older that used dCXR CAD for asymptomatic TB screening. We used the following search terms: "Tuberculosis" AND ("asymptomatic" OR "subclinical") AND ("computer aided diagnosis" OR "artificial intelligence") AND "community-based screening" AND "chest radiography" AND ("diagnostic performance" OR "sensitivity"). We identified five studies reporting on microbiologically-confirmed asymptomatic TB and dCXR CAD performance. Three of five studies tested sputum only in those who were symptomatic and/or had abnormal CXR. One study did measure prevalence of asymptomatic TB by universal sputum testing of all participants, but did not report sensitivity and specificity for asymptomatic TB separately. One case-control study of CAD4TB (v7), which pooled data from five active case-finding cohorts, reported sensitivity of 61.4% and specificity of 86.7% for asymptomatic TB. However, the case-control design and inclusion of two cohorts using prevalence survey methodology and three cohorts enrolling high TB risk groups, two of which did not perform CXR on all participants, suggest potential for selection bias. Added value of this studyWe evaluated discriminatory performance of dCXR screening for asymptomatic TB among adult household contacts of TB patients, using human readers and qXR CAD (QURE.AI, India), in three communities in South Africa (Screening Cohort). Performance was benchmarked against that for symptomatic TB among adult clinic attendees (Triage Cohort), to enable comparison with traditional published approaches. All participants underwent universal sputum testing, regardless of symptom status or dCXR results. Sensitivity of human readers for asymptomatic TB in the Screening Cohort was 56.4%, compared to 72.4% for symptomatic TB in the Triage Cohort, with specificity 94.1% and 81.2%, respectively. The corresponding sensitivity of qXR CAD for asymptomatic TB, using the manufacturers 0.5 threshold score, was 69.2%, compared to 83.6% for symptomatic TB, with specificity 89.3% and 73.5%, respectively. The difference in dCXR sensitivity and specificity for asymptomatic TB between qXR CAD and human readers was 12.8% and -4.8%, respectively. The adjusted qXR threshold score (0.007) required to achieve 90% sensitivity for asymptomatic TB reduced specificity to 18.9%; and did not meet the WHO Target Product Profile (TPP) for a high sensitivity (90%), high specificity (80%) TB screening test. Implications of all the available evidenceSensitivity of community-based dCXR screening of household contacts for asymptomatic TB was low, compared to facility-based triage of symptomatic TB. Neither human reader nor qXR CAD evaluation of dCXR met the minimal WHO TPP for a high sensitivity (90%), high specificity (80%) TB screening test. Although dCXR CAD community screening would detect more than two-thirds of all people with previously undiagnosed, microbiologically-confirmed asymptomatic TB, the significant proportion of people with TB that would remain undetected, and untreated, might allow ongoing Mycobacterium tuberculosis transmission and hinder elimination efforts.

BackgroundOur group previously reported that lung cancer (LC) screening history results and subsequent timing of diagnosis are associated with significant differences in survival outcomes. As a follow-up study, we sought to develop novel personalized risk models that considered screening history for incidence cancers, interval LCs, and prevalence LCs. MethodsUsing data from the CT-arm of the NLST, four independent case-control analyses were conducted to develop parsimonious risk models. Controls (n=26,038) were those never diagnosed with LC. The four LC case groups were 270 prevalence LCs, 44 interval LCs, 206 screen-detected LCs (SDLCs) that had a baseline positive screen, and 164 SDLCs that had a baseline negative screen. For each case-control analysis, univariable analyses identified statistically significant covariates from 48 variables and then significant covariates were included into a stepwise backward selection approach to identify a model with the most informative covariates. ResultsFor prevalence LCs, the model (AUC=0.711) included age, pack-years smoked, BMI, smoking status, smoking onset age, personal history of cancer, family history of LC, alcohol consumption, and milling occupation. For interval LCs, the model (AUC=0.734) included age, smoking status, smoking onset age, cigar smoking, marital status, and asbestos occupation. For baseline positive SDLCs, the model (AUC=0.685) included age, pack-years smoked, BMI, emphysema, chemicals/plastics exposure, and milling occupation. For baseline negative SDLCs, the model (AUC=0.701) included age, pack-years smoked, BMI, smoking status, emphysema, sarcoidosis, and sandblasting occupation. ConclusionsBesides smoking and age, which are inclusion criteria for screening, these models identified other important risk factors which could be used to provide personalized LC risk assessment and screening management.

BackgroundIn extensively drug-resistant and pre-extensively drug-resistant TB, bacteriology-based monitoring often fails to capture structural lung recovery and patient-reported functional health. We aimed to characterize multidomain treatment response and examine host inflammatory and transcriptional features associated with incomplete recovery. MethodsWe conducted an ancillary analysis of a prospective, open-label, pilot study evaluating adjunctive ibuprofen in XDR-TB (NCT02781909). Participants were assessed at baseline and during treatment using TBS, chest radiography, sputum culture, SGRQ, blood cell indices, plasma cytokines, and whole-blood transcriptomic profiling. Clinical and laboratory measures were compared across outcome groups, and blood transcriptional profiles were analyzed in relation to treatment outcomes. ResultsHere we show that microbiological and symptomatic improvement occurred earlier than radiological and functional recovery. Higher baseline systemic inflammation, including elevated NLR, SII, and IL-6, as well as increased expression of interferon-related genes such as CD274 and GBP5, were associated with poorer radiological and SGRQ outcomes at 6 months. In contrast, transient elevations of IL-8 and IL-4 were associated with early bacteriological clearance. IL-8 was the only plasma biomarker consistently correlated with symptom severity, radiological findings, and functional health. ConclusionsTreatment response in drug-resistant TB is asynchronous across biological domains. Integrated host profiling identifies inflammatory and transcriptional features associated with incomplete structural and functional recovery, supporting the use of multidimensional endpoints to better capture long-term outcomes and inform individualized patient management. Plain Language SummaryPeople with highly drug-resistant tuberculosis can clear the infection but still experience lung damage and reduced quality of life after treatment. In this study, we examined recovery using several measures, including symptoms, chest X-rays, blood markers of inflammation, and gene activity, in addition to tests for tuberculosis bacteria. We analyzed data and stored samples from a small clinical trial to see how these measures changed over time. We found that lung structure and quality of life improved more slowly than bacterial clearance. People with higher levels of inflammation before treatment were more likely to have ongoing lung changes and poorer quality of life later. These results suggest that tuberculosis care should look beyond bacterial clearance and include monitoring inflammation to better support long-term recovery.

ABSTRACT Background: Corticosteroids reduce mortality in severe COVID-19 requiring oxygen or invasive mechanical ventilation, yet emerging data suggest that SARS-CoV-2-associated acute lung injury is biologically heterogeneous and that treatment response may vary across molecularly defined disease states. Lung-derived molecular endotypes of severe COVID-19-associated acute lung injury have been described, but direct molecular profiling is not routinely available at the bedside. We evaluated whether a clinical predictor of previously defined lung molecular endotype identifies heterogeneity in corticosteroid treatment effect among mechanically ventilated patients with COVID-19. Methods: We utilized a single-center cohort of 5,000 patients with COVID-19 treated at the University of North Carolina Hospital between January 1, 2020, and December 31, 2022, to emulate a target trial assessing the effect of corticosteroid receipt on mortality, length of stay, and incident organ support. Confounding was addressed through inverse probability of treatment weighting (IPTW). Outcomes for severely ill patients requiring mechanical ventilation were compared to the RECOVERY trial results, with subsequent moderation analysis and stratified analysis by clinically predicted lung molecular endotype and vaccination status. The primary outcome was 28-day mortality. Secondary Outcomes were time to discharge alive and progression to additional organ support. Results: This emulated target trial showed a directionally favorable but non-statistically significant association between corticosteroid treatment and reduced 28-day mortality in patients requiring mechanical ventilation for SARS-CoV-2 infection. A clinical predictor of lung molecular endotype moderated the effect of corticosteroids on 28-day mortality (p-value for interaction 0.038) and identified distinct predicted endotype-specific treatment effect. Corticosteroid treatment was associated with lower 28-day mortality in the predicted Hyper-Inflammatory endotype (OR 0.62, 95% CI 0.39, 0.99) but not in the predicted Metabolic Dysregulation endotype (OR 1.15, 95% CI 0.82, 1.61). We did not detect significant effect modification by vaccination status (p-value for interaction 0.65), although inference was limited by the small, vaccinated subgroup (28-mortality OR 0.78, 95% CI 0.37, 1.65 in vaccinated vs 0.94, 95% CI 0.70, 1.26 in unvaccinated). Conclusions: In this target trial emulation of mechanically ventilated patients with severe COVID-19, corticosteroid treatment showed a directionally favorable but non-statistically significant association with reduced 28-day mortality in the overall cohort. However, a clinical predictor of lung molecular endotype identified significant heterogeneity in treatment effect, with benefit concentrated in the predicted Hyper-Inflammatory endotype and no apparent benefit in the predicted Metabolic Dysregulation endotype. These findings support prospective validation of clinically deployable endotype-guided corticosteroid treatment strategies in acute lung injury and ARDS.

Rationale: Sputum-based testing using Xpert MTB/RIF Ultra (Xpert) is the most common molecular testing method for diagnosing tuberculosis (TB). Objectives: To evaluate whether sputum quality influences Xpert positivity and diagnostic accuracy. Methods: We screened consecutive people for presumptive TB in India, the Philippines, Vietnam, Nigeria, South Africa, Uganda, and Zambia as part of the R2D2 TB Network and ADAPT studies. Participants provided 2-3 sputum samples for Xpert and culture reference testing. The quality of the first sputum sample was graded following standardized procedures by trained research staff and used for Xpert testing. We performed logistic regression to evaluate whether sputum grade was independently associated with Xpert positivity, and calculated sensitivity and specificity of Xpert against a culture-based microbiological reference standard (MRS). Measurements and Main Results: Among 1,855 participants, 798 (43%) were female, 348 (19%) were living with HIV (PLHIV), and 1795 (97%) had a cough of [≥]2 weeks. Overall, 313 (17%) had a positive Xpert result. Most sputum samples were salivary (83%). Xpert positivity was lowest among salivary samples (16.1%) and highest among purulent samples (31.2%). After adjusting for demographic and clinical variables, there was no significant association between any sputum grade and Xpert positivity. Xpert sensitivity (salivary: 89%, mucoid: 91%, mucopurulent: 87%, purulent: 100%) and specificity (>98%) were high across sputum grades. Conclusions: Sputum quality was not independently associated with Xpert positivity and Xpert sensitivity was high across all sputum grades. These findings support molecular testing of all sputum samples for TB diagnosis regardless of macroscopic appearance.

BackgroundTargeted Universal Tuberculosis Testing (TUTT) may increase tuberculosis (TB) case detection by including people who are not actively seeking TB care but are at high risk of the disease.Non-invasive tongue swab (TS) testing may facilitate TUTT. We evaluated two TS testing protocols in people with HIV (PWH) tested irrespective of TB symptoms. MethodsStudy staff collected Copan FLOQSwab and Medline foam swab specimens, alongside urine and sputa, from PWH, most of whom were presenting for antiretroviral therapy initiation at primary healthcare clinics in KwaZulu-Natal, South Africa. FLOQSwabs were tested by sequence-specific magnetic capture (SSMaC) with qPCR (FLOQSwab-SSMaC). Foam swabs were tested by centrifuge-sedimentation and high-volume qPCR (foam-sedimentation). Urine lipoarabinomannan was detected using LF-LAM. The extended microbiological reference standard (eMRS) comprised any positive result on Xpert Ultra and/or liquid culture of sputum. ResultsWe enrolled 251 participants (median age 34 years, 56% female, 67% with self-reported TB symptoms). Participants had a median CD4 count of 347 cells/{micro}l, and 16% (40/251) had prior TB. FLOQSwab-SSMaC was 43% sensitive (13/30) and 100% specific (131/131) relative to eMRS. Foam-sedimentation was 47% (9/29) sensitive and 100% (176/176) specific. Sensitivity increased to 52% (FLOQSwab-SSMaC) and 50% (foam-sedimentation) when sputum Xpert Ultra Trace positive results were excluded from eMRS. TS was more sensitive than urine LAM, and both sample types were more sensitive when CD4 counts were below 200. DiscussionTS testing detected about half of PWH with TB and outperformed urine LAM within this population, including among PWH with low CD4 counts. SummaryTB testing approaches using tongue swabs (TS), combined with molecular methods, have the potential to identify people with TB in settings where sputum collection is not practical. People living with HIV are an at-risk group that could benefit from non-sputum based targeted TB testing programs.

Purpose: We systematically reviewed the evidence for three questions on screening for lung cancer with computed tomography (CT): benefits (from randomized trials) and harms of screening versus no screening/minimal intervention or alternative screening approaches (e.g., selection criteria, screening intervals); relative importance that informed patients place on the potential benefits and harms of screening (patient preferences); and comparative effects from observational studies of different screening selection criteria (using risk prediction models) or nodule classification systems compared with those used in the screening trials. Methods: A working group of primary care and specialist clinicians (previously members of Canadian Task Force on Preventive Health Care) and topic experts provided input into the eligibility criteria and key potential effect moderators, rated outcomes for their importance to decision making, and developed decision thresholds for use when making conclusions and assessing certainty of the evidence. Critical outcomes of screening effects included all-cause mortality, lung-cancer mortality, and overdiagnosis (via excess cancer incidence from screening). For patient preferences, we sought direct preference data via (i) disutilities of relevant health states (measuring their impact on ones health-related quality of life on a scale of 0 [perfect health] to 1 [death], mainly using EQ-5D), and (ii) other preference-based data, such as outcome trade-offs, as well as indirect preference data via (iii) the relative importance of benefits versus harms inferred from attitudes, intentions, and behaviors towards screening among eligible patients informed with estimates of the outcomes. For screening benefits and harms and for patient preferences, we searched three databases (MEDLINE, Embase, and Central & MEDLINE, Scopus, and EconLit, respectively) to July 11, 2025. For screening studies published prior to 2015 we relied on searches for other reviews, and for patient preferences our search was limited to 2012-onwards. For comparative effects, we searched MEDLINE and Embase from 2019 to September 23, 2025, with reliance on other reviews for studies published 2012-2018. Reference lists were scanned and trial registries searched. For the main searches, two independent reviewers screened titles and abstracts and then full texts; for search updates we applied AI to assist with title and abstract screening. Data extraction and analysis were undertaken by single reviewers, with verification; risk of bias and GRADE certainty assessments were undertaken independently by at least two reviewers. Data were pooled where suitable using random effects methods appropriate to the outcome metric and prevalence. Subgroup analyses explored heterogeneity (e.g., sex, number of rounds, type of comparator, sensitivity of nodule management, type of utility measurement). When not pooled (e.g., patient preferences based on screening intentions) data were analyzed by grouping studies based on factors such as population, setting, exposure, and outcomes, with consideration of study size and risk of bias. Conclusions and certainty assessments for screening effects were based on estimates of absolute effects. Results: We included 85 studies (N=640,537; 13 trials) on screening benefits and harms, 59 on patient preferences (33 [N=42,219] on disutilities and 26 [N=10,829] other studies), and 16 for comparing trial (National Lung Screening Trial [NLST]) and LungRADs nodule management, either directly (2 studies, N=26,978) or indirectly (14 studies, N=1,102,285). Screening benefits and harms: Findings from nine trials (N=94,530) examining low-dose CT (LDCT) screening on all-cause (RR 0.97, 95% CI 0.93 to 1.01; 3.7 fewer [8.5 fewer to 1.2 more] per 1000) and lung-cancer mortality (RR 0.87, 95% CI 0.79 to 0.96; 4.0 fewer [1.2 to 6.4 fewer] per 1000) offered low and moderate certainty, respectively, that screening previous/current 20-30 pack-year smokers 50-74 years old 3-4 times will probably result in at least 1 (all-cause) and 2 (cause-specific) fewer deaths per 1000 screened after 10-12 years. The absolute effects may not apply to participants at the lowest baseline risk for lung-cancer incidence (e.g., <1.5% over 6 years) or death. Seven trials (N=35,161) contributed to meta-analysis for overdiagnosis (RR 1.19, 95% CI 1.03 to 1.37; 8.4 [1.3 to 16.3] per 1000), and our certainty was moderate that LDCT screening 3-4 times will probably result in at least 2.5 cases of overdiagnosis per 1000 screened over 10 years. For important outcomes, we had high certainty that screening 3-4 times results in at least 75 people per 1000 screened (and probably at least 225) having at least one benign biopsy/false positive, 150 having one or more incidental findings (likely at least 450), and 50 (probably at least 100) having a clinically significant/actionable incidental finding, but probably does not have an important impact on major complications or death from invasive testing among those without cancer. Though undergoing a LDCT scan probably causes little-to-no psychosocial harm, having a positive screening result likely causes at least a small degree of harm (i.e., 4-8% change from baseline), especially for the 10-15% having to undergo invasive procedures where some may experience moderate harm. Among those without cancer, these effects may last for several months while the diagnostic process is underway, though moderate certainty evidence found little-to-no effects remaining after 6 months from diagnostic resolution. Comparative effects: Findings from applying different baseline predicted risks for lung-cancer incidence or mortality to the trial populations (i.e., alternative selection criteria) were considered with the effects from screening benefits and harms. Using LungRADs instead of NLST nodule management (among NLST eligible people) probably reduces the false positive rate substantially (about half), though the number of false positives still exceeded the decision threshold of 75 per 1000 and the effects for benefits or other harm outcomes are not known. Patient preferences: Findings showed little-to-no disutility (i.e., <0.04) from a positive screening test (moderate certainty) or a false positive result (low certainty). Low-certainty evidence found there may be little-to-no disutility from a stage I-IIIA cancer diagnosis (before treatment) but small but important disutilities from a stage IIIB/IV diagnosis, during first-line treatment of any stage (though possibly moderate disutility of about 0.09 for stage IIIB/IV), and after treatment for stage IIIB/IV but not stage I-IIIA (without progression) where effects were inconsistent but indicated that any disutility may not be long-lasting. Findings for stage I-IIIA are likely most relevant for understanding the consequences of overdiagnosis. For stated preferences between outcomes, there was low certainty evidence that a small majority (51-75%) of people may accept 69-122 false positives and at least 1.3 cases of overdiagnosis per prevented lung-cancer death, and think that the reduction in lung-cancer mortality is more important than experiencing one of the relevant harms. After being informed about anticipated benefits and harms from screening (with the largest screening effects shown to those at higher baseline risk), progressively more people preferred screening (mainly via intentions) as the net benefit of screening improved from low [25-50% preferred] to moderate [51-75%] to high [>75%]. Conclusions: This review provides contemporary data on the benefits and harms of LDCT screening after at least a decade of follow-up and makes conclusions based on absolute effects while considering thresholds for decision making. Across the reviews, findings indicate that screening those aged 50-74 years with 3-4 rounds of LDCT will lead to benefits and harms for which a majority, but not all, eligible people probably find acceptable and worthwhile. While current nodule management using LungRADs likely reduces false positives, whether it impacts the benefits of screening is less certain and worth further research. Further, comparative prospective studies are lacking to determine the effects from screening for those not meeting the minimum age (50 years) and smoking history criteria in the trials, despite having an equivalent risk for lung cancer.

BackgroundLung cancer screening can reduce lung cancer mortality through early detection, but uptake of the NHS Targeted Lung Health Check (TLHC) programme remains low. Behaviourally informed invitation messages have been proposed as a low-cost approach to increase attendance, but evidence of their effectiveness in lung cancer screening is mixed. Few intervention studies used evidence-based behaviour change frameworks, and rarely tailored invitation strategies to empirically identified barriers and enablers. MethodsIn an online experiment, 3,274 adults aged 55-74 years and with a history of smoking were randomised to see one of four behaviourally informed invitation messages or a control message. Participants then rated their intention to attend a TLHC appointment, and selected barriers and enablers to attending from a pre-defined list, which were classified according to the Theoretical Domains Framework. Invitation messages were mapped to Behaviour Change Techniques using the Theory and Techniques Tool. Message conditions were compared on intention to attend TLHC using bootstrapped ANOVA followed by pairwise comparisons. Exploratory counterfactual mediation analyses examined the role of fear in intention to attend. ResultsBehaviourally informed invitation messages did not meaningfully increase intention to attend TLHC compared with the control message. While a GP-endorsed message showed a small potential benefit relative to the other conditions, this finding was not robust after adjustment for multiple comparisons. Participants most frequently reported barriers related to Emotion (particularly fear), Social Influence, and Knowledge, while Beliefs about Consequences emerged as the primary enabler of attendance. Only around half of reported barriers and enablers were addressed by the invitation messages. Exploratory analyses found that fear was associated with lower intention to attend a TLHC appointment, yet none of the behaviourally informed messages appeared to reduce fear compared to the control message. ConclusionsImproving lung cancer screening uptake will likely require invitation messages that directly address emotional concerns, particularly fear, alongside credible recommendations. These findings highlight the importance of systematically aligning invitation message content with empirically identified behavioural influences when designing scalable interventions to improve lung cancer screening uptake. Contributions to the literatureO_LIAttendance at the NHS Targeted Lung Health Check remains low despite being a UK policy priority. This study provides evidence to inform invitation strategies for ongoing and future screening programmes. C_LIO_LIBehavioural economics frameworks are widely used in health messaging but lack systematic methods for linking behavioural influences with intervention content and evaluation. C_LIO_LIThis study demonstrates how Behaviour Change frameworks can diagnose why behaviourally informed messages may fail, by assessing alignment between intervention content and population-specific barriers and enablers. C_LIO_LIFindings suggest that messaging interventions targeting lung cancer screening attendance may have limited impact when they do not address emotional and social influences. C_LI

Background: Wearing facemasks and practising social distancing slow the spread of respiratory pathogens. However, in the event of a new pandemic emerging, the willingness of populations to voluntarily adopt these behaviours is unclear. Methods: A discrete choice experiment was conducted among 2,006 UK-based adults. Participants were presented with hypothetical scenarios describing the emergence of a respiratory virus pandemic and were asked to choose when they would wear facemasks and practise social distancing. A mixed multinomial logit model was used to jointly estimate how disease severity and prevalence, uncertainty in these quantities, and individual-level characteristics influence behavioural choices. Findings: Participants were averse to facemasks and social distancing in the absence of pandemic risk. For each ten-unit increase in severity (10 additional hospitalisations/1,000 infections), the odds of always wearing a facemask outside the home increased by 15.9% (95%CI: 14.3%, 17.5%), relative to rarely/never, and the odds of avoiding all people as much as possible increased by 16.4% (14.6%, 18.2%), relative to not avoiding anyone. Greater disease prevalence, uncertainty in disease severity or disease prevalence, a university education, prior COVID-19 vaccination and non-white ethnicity were also associated with choosing to always wear facemasks and avoid all people as much as possible. The probability of participants choosing to rarely/never wear facemasks varied from 13.4% (11.9%, 14.9%) in the lowest-risk scenario to 1.4% (1.2%, 1.7%) in the highest-risk scenario. Interpretation: Perceived risks of disease and associated uncertainty drive intention of UK adults to adapt their behaviour in a future pandemic.

IntroductionAlthough temporal variation is the hallmark of asthma, recommended diagnostic approaches largely rely on single clinic-based measurements. Ambulatory monitoring captures diurnal and day-to-day variability and may therefore enhance diagnostic accuracy. We evaluated the clinical feasibility and potential utility of home spirometry and fractional exhaled nitric oxide (FeNO) monitoring in asthma diagnosis. MethodsSymptomatic, untreated adults with GP-suspected asthma underwent diagnostic tests including bronchodilator reversibility, in-clinic FeNO, blood eosinophil counts and bronchial challenge. Participants measured spirometry and FeNO four times daily over one week; during the second week spirometry were measured twice daily. The reference standard was provided (asthma/not-asthma) by an expert panel of at least two asthma specialists based on clinical history and the results of all in-clinic testing; home spirometry (except for peak expiratory flow) and FeNO measurements were blinded to the panel. ResultsOf 67 eligible participants, 51(76%) were recruited, and 38 had asthma confirmed or excluded by the panel. 1058 home spirometry measurements were obtained from 37(73%) participants; 848 home FeNO readings were obtained from 39(76%) participants. Among those completing at least one home measurement, median (IQR) adherence was 66.7(58.6-97.6)% for spirometry and 78.5(51.8-103.6)% for FeNO. Collection of health impact data for economic evaluation was feasible. In participants with a confirmed diagnostic outcome who completed home measurements (FeNO: n=32; spirometry: n=28), the putative home-testing metrics demonstrated high sensitivities at [&ge;]90% specificity, and outperformed peak expiratory flow diurnal variability. Incorporating home testing into the BTS/NICE/SIGN 2024 diagnostic pathway had the potential to reduce reliance on bronchial challenge testing by 57%. ConclusionsHome spirometry and FeNO testing and the prospective collection of health-economic data in the diagnostic setting were feasible. Home-based testing strategy showed early potential to improve asthma diagnosis and pathway efficiency. These findings support further evaluation through an adequately powered diagnostic accuracy study and health-economic assessment. Key messagesO_LIWhat is already known on this topic: Asthma can be difficult to diagnose, as objective tests may be normal when assessments are performed during periods of minimal or intermittent symptoms. C_LIO_LIWhat this study adds: Our data suggest that home spirometry and FeNO monitoring could be successfully implemented within a diagnostic accuracy trial. Participants were able to perform these tests reliably in the home environment. C_LIO_LIHow this study might affect research, practice or policy: The early findings suggest that home-based physiological monitoring may offer additive diagnostic value beyond standard clinic-based assessments and could reduce reliance on bronchial challenge testing. These results provide a clear rationale for larger diagnostic accuracy trials and for undertaking early health-economic modelling to assess the potential impact on clinical pathways and resource utilisation. C_LI

BackgroundRecent guidelines differ in how fractional exhaled nitric oxide (FeNO) is used to diagnose school-age asthma, either as one of several tests with a cut-off at 25 ppb or as a single rule-in test at 35 ppb. Evidence on its diagnostic performance and clinical utility in subgroups remain limited. MethodsWe analysed data from 1,979 school-age children in the Swiss Paediatric Airway Cohort referred for suspected asthma. We investigated FeNO performance with diagnosis by paediatric pulmonologists as reference standard using receiver operating characteristics curves, selected cut-offs and simulated predictive values across different prevalence. Subgroup analyses considered allergic sensitisation with allergic rhinitis and current inhaled corticosteroid (ICS) use. ResultsIn the overall cohort (asthma diagnosis 70%), FeNO showed poor discrimination for asthma (AUC 0.66; 95% CI 0.64-0.68) with an optimal cut-off at 22 ppb. At 25 and 35 ppb, sensitivity was low (43%, 95% CI 40-46; 31%, 95% CI 29-34) and specificity moderate to high (84%, 95% CI 77-84; 90%, 95% CI 87-92). Positive predictive value at 35 ppb was 88% and was 57% when simulated at a prevalence of 30%. FeNO had no diagnostic value in non-sensitised children and lower performance in sensitised children with allergic rhinitis than in those without (AUC 0.59 vs 0.68). Current ICS use did not influence performance. ConclusionFeNO has limited diagnostic performance as a stand-alone test for school-age asthma, and underlying asthma prevalence and allergic characteristics should be considered in the interpretation.

BACKGROUNDRapid, interoperable whole-genome tools for Mycobacterium tuberculosis complex (MTBC) surveillance remain limited for harmonised lineage assignment across recognised lineages and simultaneous resistance-associated variant detection. AIMTo develop and validate Pathotypr, an alignment-free tool for harmonised MTBC lineage assignment and resistance genotyping from assemblies and raw reads. METHODSWe reconstructed an MTBC phylogeny from 26,813 genomes using 609,003 polymorphic sites, derived an updated lineage marker backbone, and implemented a k-mer/Random Forest framework with marker-based lineage and WHO catalogue-based resistance calling. Performance was evaluated on 498 RefSeq assemblies, 88,071 UShER-TB typed sequencing samples, 162 clinical read sets for closest-reference matching, and 7,148 CRyPTIC isolates with phenotypic drug susceptibility data. RESULTSPathotypr supported all 14 currently recognised MTBC lineages (L1-L10, A1-A4). On 498 complete genomes, marker-based and alignment-free lineage calls were 100% concordant, and prediction accuracy remained 100% on 254 independent assemblies. In 88,071 non-ambiguous UShER-TB samples, root-lineage concordance with TB-Profiler was 100%, while Pathotypr additionally identified lineage 10, A1 and A2. Resistance predictions showed 85.0% genotype-phenotype concordance overall, with high performance for rifampicin (95.8% sensitivity, 95.0% specificity) and isoniazid (93.0%, 97.9%). Runtime was about 1 second per sample, enabling analysis of 88,071 samples in approximately 24 hours on four threads. In the MDR-enriched CRyPTIC collection, Pathotypr supported reconstruction of 135 probable introduction events into Germany, Italy and Ukraine; 33.7% of introduction-associated isolates carried MDR/pre-XDR genotypes. CONCLUSIONPathotypr enables rapid, harmonised MTBC lineage assignment and high-confidence resistance screening, supporting near real-time and cross-border tuberculosis surveillance.

Introduction: Current tuberculosis (TB) screening tools, such as the WHO four-symptom screen (W4SS), lack sufficient sensitivity and specificity for effective community-based active case finding, contributing to both missed diagnoses and unnecessary diagnostic evaluations. This study aimed to develop and validate a machine learning (ML) model to improve TB risk prediction among persons aged >=15 years in community settings of Zambia and South Africa. Methods: A large, harmonized dataset was created from four community-based TB prevalence surveys in South Africa and Zambia (N=169,813), restricted to individuals not under treatment at the time of survey. A binary reference outcome was defined based on available microbiological and radiographic data, grouping individuals as either 'Possible TB' or 'Unlikely TB'. An XGBoost model was trained on 80% (N=135,854) of the data using demographic, clinical, and socio-economic variables, and model interpretability was assessed using SHapley Additive exPlanations (SHAP) values. Internal validation was performed using a 20% hold-out test set (N=33,959). Model performance was assessed using discrimination, calibration, and clinical utility measures compared to the W4SS and against WHO's 2025 Target Product Profile (TPP) for a tool in a two-step screening algorithm. Results: Overall, 16,413 (9.7%) of individuals were labelled as 'Possible TB'. On the test set, the XGBoost model yielded an area under the curve (AUC) of 79.7% (95% CI: 78.7, 80.7), outperforming the W4SS (AUC 57.0%; 95% CI: 56.1, 57.8). The XGBoost model achieved 81.5% sensitivity (95% CI: 77.6, 84.9) at a 60% specificity threshold. This exceeded the W4SS, which achieved only 38.2% sensitivity (95% CI: 36.5, 39.9) on the same dataset. SHAP analysis identified age, previous TB treatment, times treated for TB and unemployment as the primary contributors to risk. Conclusion: The ML XGBoost model shows promise as a screening tool to support community-based active case finding activities prior to diagnostic testing. However, as performance remained below TPP targets, and adding variables, e.g. on geolocation, could be considered.

Background Genetic studies to date are yet to define the major portion of the genetic risk for adult-onset pulmonary fibrosis (PF). Further the dearth of knowledge of clinically actionable variants for PF is hampering efforts to implement genetic testing to aid early diagnosis and improve disease management. Here we evaluated the contribution of rare and common variants to PF in cohorts with and without a family history of PF. Method Whole genome sequencing (WGS) was performed in a familial cohort comprising PF cases and their family members (85 individuals representing 55 families); and 122 cases from the Australian IPF Registry (AIPFR) with and without a self-reported family history of PF. WGS data were interrogated for rare potentially PF-causing variants in 33 genes previously associated with PF. Variants that were rare and predicted to be likely causative were formally curated using the American College of Medical Genetics and Association for Molecular Pathology (ACMG-AMP) guidelines. Additionally, to examine the common risk variant contribution, a weighted polygenic risk score (PRS) was generated using 16 previously IPF-associated common SNPs. PRS were generated from WGS for the 85 clinically confirmed familial cases and 122 AIPFR cases. In the remaining 202 AIPFR cases, PRS were generated from TaqMan genotyping data. Results Interrogation of WGS generated from 207 individuals with PF revealed multiple rare putative pathogenic variants in both familial and AIPFR cohorts. Formal curation revealed pathogenic (P) or likely pathogenic (LP) variants confirmed in TERT or RTEL1 in four families (7.3%) with the majority of remaining variants classified as variants of uncertain significance (VUS; 12.7%) in seven additional families. Amongst AIPFR participants, four variants met the threshold for classification as P/LP variants (3.3%), with a further six individuals found to harbour VUS following curation (4.9%). Overall weighted PRS did not differ significantly between individuals with familial PF or with no reported family history. However, PRS in all patient groups were significantly elevated compared with population controls. Conclusion VUS remain the major portion of rare variants identified in known PF -related genes. For ~80% individuals with a confirmed family history no potentially causative variants were identified in known PF related genes nor was there evidence that a high burden of common variants contributed to risk in these families. Similarly, we found no evidence that a high burden of common variants contributes to a significant proportion of risk PF in those individuals with no reported family history.

Background Tuberculosis remains the leading infectious cause of death worldwide. In the WHO African region, declining incidence has coincided with antiretroviral therapy (ART) scale-up, though whether this reflects reduced progression to disease or reduced transmission is unclear. We evaluated how ART and symptom status influence within-household Mycobacterium tuberculosis complex (MTBC) transmission risk. Methods We conducted a case-contact household study in rural South Africa, enrolling index adults with bacteriologically-confirmed pulmonary tuberculosis. MTBC immunoreactivity was measured in all child household contacts (aged 2-14 years) as a proxy measure of within-household transmission. We assessed the influence of index person ART status and symptom status, and explored effect-measure modification of the association between index person HIV status and transmission risk by sex. Results Among 755 child contacts of 296 index persons, effective ART was not associated with within-household MTBC transmission risk (risk ratio [RR], 1.07; 95% CI, 0.66-1.74). Among PLHIV engaged in ART care, WHO TB four-symptom screen (WHO4SS) status was not associated with transmission risk (RR, 0.80; 95% CI, 0.43-1.47), although absence of reported cough reduced risk (RR, 0.61; 95% CI, 0.38-0.96). A pronounced interaction between sex and HIV status was observed: HIV-negative women had the highest within-household MTBC transmission risk (30.5% vs. 14.3% in women with HIV) whereas risks were similar between HIV-positive and HIV-negative men. Conclusions We found no evidence that effective ART or WHO4SS status influenced within-household MTBC transmission risk, though confidence intervals were wide. Absence of reported cough was associated with lower risk, and transmission risk was highest among child contacts of HIV-negative women. These findings suggest reported cough is a useful marker of transmission risk and that routine tuberculosis screening within ART care may reduce transmission from PLHIV; intensified efforts are nonetheless needed to achieve earlier tuberculosis detection in HIV-negative individuals.

Background Scalable, non invasive tools are critically needed to improve early lung cancer detection and optimize primary care referral pathways. We evaluated Inflammacheck, a point-of-care device utilizing exhaled breath condensate (EBC) H2O2 and physiological parameters with machine learning, for non-invasive lung cancer detection in a real-world screening population. Methods ExPeL study participants, from the UK Targeted Lung Health Check (TLHC) programme, included individuals with suspected lung cancer and low-risk ever-smoker controls. EBC was collected via Inflammacheck, measuring H2O2;, end-tidal CO2;, humidity, temperature, and exhalation flow rate. Multivariate analyses (PCA, LDA, Mahalanobis distance) assessed intrinsic group separation. SMOTE-balanced data trained supervised machine learning models (stacked and voting ensembles), which were then evaluated on held-out test sets. In parallel, untargeted LCMS metabolomics was performed to identify discriminatory molecular features. Results Analysing 34 participants with valid EBC data, 83% of cancer cases were early-stage (I or II), reflecting a screening population. Multivariate analysis clearly separated lung cancer and controls across PCA, LDA, and Mahalanobis mapping. The voting ensemble model achieved: Accuracy 85.7%, Sensitivity 80%, Specificity 100%, Precision (PPV) 100%, ROC AUC 0.90, MCC 0.73. Crucially, no false positives were identified. EBC variables revealed greater dispersion in cancer patients, reflecting physiological heterogeneity missed by univariate analysis. Untargeted metabolomics identified 2,132 features, with four key metabolites yielding an AUC of 0.969 for cancer discrimination. Discussion Inflammacheck effectively distinguishes early-stage lung cancer via a rapid, non-invasive breath test, findings which are highly relevant for primary care and screening triage, where non-specific symptoms and low prevalence pose challenges.

Rationale: Preclinical familial pulmonary fibrosis (FPF) represents an early stage of fibrotic lung disease, yet the compartment- and cell-specific molecular programs preceding fibrosis remain poorly understood. Objective: To define spatially organized molecular signatures associated with preclinical FPF and identify tissue-informed circulating biomarkers linked to early fibrotic remodeling. Methods: We performed integrated multi-omic profiling of histologically preserved and remodeled lung regions from subjects with preclinical FPF, Idiopathic Pulmonary Fibrosis (IPF), and controls using spatial transcriptomics, single-nucleus RNA sequencing (snRNAseq), and blood proteomics. Differential expression and pathway enrichment analyses were performed across spatial compartments and epithelial cell states. Results: Histologically preserved lung regions in preclinical FPF demonstrated transcriptional abnormalities including stress-response, ciliary, and extracellular matrix-associated programs despite minimal architectural distortion. Spatial analyses identified alterations in alveolar niche molecular programs accompanied by increasing profibrotic signaling across preserved and tissue remodeled lung compartments. Compared with advanced IPF, preclinical FPF retained epithelial repair and surfactant-associated signatures. Integration with snRNAseq demonstrated enrichment of alveolar and airway epithelial cell dysregulated states associated with transitional phenotypes previously implicated in IPF. Compartment- and epithelial-associated transcriptional signatures identified in lung tissue were partially represented in the peripheral blood. Conclusion: Preclinical FPF is characterized by compartment- and cell-specific molecular programs that precede established fibrosis. We identified distinct alveolar, airway, and vascular molecular signatures and epithelial remodeling states represented in the peripheral blood. These findings provide an initial framework for molecular classification of early stages of pulmonary fibrosis and support future studies evaluating minimally invasive approaches for disease stratification and precision therapeutics.

Background Microbiological confirmation of paediatric pulmonary tuberculosis is frequently unattainable, rendering chest radiography a critical yet underutilised diagnostic tool. Methods We conducted a retrospective diagnostic accuracy study of the qXR version 4.2.1 (Qure.ai), a paediatric optimized computer-aided detection (CAD) algorithm, for pulmonary tuberculosis. Diagnostic performance was assessed against microbiological (MRS) and clinical reference standards (ClRS). Bayesian latent class analysis (LCA) was applied to address the imperfection of both reference standards in children. Performance was quantified using area under the receiver operating characteristic curve (AUROC) and estimates of sensitivity and specificity. Results We included digital chest radiographs of 932 Gambian children (< 15 years) comprising 80 (9%) children with confirmed tuberculosis, 163 (17%) with unconfirmed tuberculosis, and 689 (74%) classified as unlikely tuberculosis. Against MRS, qXR demonstrated AUROC, sensitivity and specificity of 0.68 (95% CI, 0.61 to 0.75), 54% (95% CI, 43 to 64%), and 82% (95% CI, 79 to 84%), respectively. Against ClRS, the AUROC, sensitivity and specificity were 0.73 (95% CI, 0.69 to 0.77), 41% (95% CI, 34 to 49%), and 87% (95% CI, 84 to 89%), respectively. Bayesian LCA, assuming conditional independence, estimated sensitivity of 79% (95% CrI, 65 to 89%) and specificity of 82% (95% CrI, 79 to 84%). Assuming conditional dependence between qXR and expert radiologist, and between culture and Xpert, estimated sensitivity increased to 89% (95% CrI, 71 to 98%), with specificity remaining at 82% (95% CrI, 79 to 84%). Conclusions Paediatric optimized qXR algorithm provides a valuable complementary tool for diagnosis of paediatric pulmonary tuberculosis. Conventional reference standards likely underestimate the true diagnostic performance of CAD systems in children.