Sputum

Rationale: Understanding the role of the airway microbiome in chronic obstructive pulmonary disease (COPD) inflammatory endotypes may help to develop microbiome-based diagnostic and therapeutic approaches. Objectives: To understand the association of the airway microbiome with neutrophilic and eosinophilic COPD at stability and during exacerbations. Methods: An integrative analysis was performed on 1,706 sputum samples collected longitudinally from 510 patients with COPD recruited at four UK sites of the BEAT-COPD (Biomarkers to Target Antibiotic and Systemic COPD), COPDMAP (Chronic Obstructive Pulmonary Disease Medical Research Council/Association of the British Pharmaceutical Industry), and AERIS (Acute Exacerbation and Respiratory Infections in COPD) cohorts. The microbiome was analyzed using COPDMAP and AERIS as a discovery data set and BEAT-COPD as a validation data set. Measurements and Main Results: The airway microbiome in neutrophilic COPD was heterogeneous, with two primary community types differentiated by the predominance of Haemophilus. The Haemophilus-predominant subgroup had elevated sputum IL-1β and TNFα (tumor necrosis factor α) and was relatively stable over time. The other neutrophilic subgroup with a balanced microbiome profile had elevated sputum and serum IL-17A and was temporally dynamic. Patients in this state at stability were susceptible to the greatest microbiome shifts during exacerbations. This subgroup can temporally switch to both neutrophilic Haemophilus-predominant and eosinophilic states that were otherwise mutually exclusive. Time-series analysis on the microbiome showed that the temporal trajectories of Campylobacter and Granulicatella were indicative of intrapatient switches from neutrophilic to eosinophilic inflammation, in track with patient sputum eosinophilia over time. Network analysis revealed distinct host-microbiome interaction patterns among neutrophilic Haemophilus-predominant, neutrophilic balanced microbiome, and eosinophilic subgroups. Conclusions: The airway microbiome can stratify neutrophilic COPD into subgroups that justify different therapies. Neutrophilic and eosinophilic COPD are interchangeable in some patients. Monitoring temporal variability of the airway microbiome may track patient inflammatory status over time.

In vitro culture media are being developed to understand how host site-specific nutrient profiles influence microbial pathogenicity and ecology. To mimic the cystic fibrosis (CF) lung environment, a variety of artificial sputum media (ASM) have been created. However, the composition of these ASM vary in the concentration of key nutrients, including amino acids, lipids, DNA, and mucin. In this work, we used feature-based molecular networking (FBMN) to perform comparative metabolomics of Pseudomonas aeruginosa, the predominant opportunistic pathogen infecting the lungs of people with CF, cultured in nine different ASM. We found that the concentration of aromatic amino acids and iron from mucin added to the media contributes to differences in the production of P. aeruginosa virulence-associated secondary metabolites. IMPORTANCE Different media formulations aiming to replicate in vivo infection environments contain different nutrients, which affects interpretation of experimental results. Inclusion of undefined components, such as commercial porcine gastric mucin (PGM), in an otherwise chemically defined medium can alter the nutrient content of the medium in unexpected ways and influence experimental outcomes.

BackgroundPseudomonas aeruginosa is a multidrug-resistant pathogen causing recalcitrant pulmonary infections in people with cystic fibrosis (pwCF). Cystic fibrosis transmembrane conductance regulator (CFTR) modulators have been developed that partially correct the defective chloride channel driving disease. Despite the many clinical benefits, studies in adults have demonstrated that while P. aeruginosa sputum load decreases, chronic infection persists. Here, we investigate how P. aeruginosa in pwCF may change in the altered lung environment after CFTR modulation.MethodsP. aeruginosa strains (n = 105) were isolated from the sputum of 11 chronically colonized pwCF at baseline and up to 21 months posttreatment with elexacaftor-tezacaftor-ivacaftor or tezacaftor-ivacaftor. Phenotypic characterization and comparative genomics were performed.ResultsClonal lineages of P. aeruginosa persisted after therapy, with no evidence of displacement by alternative strains. We identified commonly mutated genes among patient isolates that may be positively selected for in the CFTR-modulated lung. However, classic chronic P. aeruginosa phenotypes such as mucoid morphology were sustained, and isolates remained just as resistant to clinically relevant antibiotics.ConclusionsDespite the clinical benefits of CFTR modulators, clonal lineages of P. aeruginosa persist that may prove just as difficult to manage in the future, especially in pwCF with advanced lung disease.

BackgroundImproved diagnostic tools for tuberculosis that are suitable for use in peripheral health centers are essential for reducing the persistent gap between estimated and notified cases. The diagnostic accuracy and usability of the MiniDock MTB test for detecting pulmonary tuberculosis is unknown.MethodsWe conducted a prospective, cross-sectional study at outpatient centers in India, Nigeria, the Philippines, South Africa, Uganda, Vietnam, and Zambia. Patients 12 years of age or older with presumptive pulmonary tuberculosis were enrolled between September 12, 2024, and March 31, 2025. Assessment with MiniDock MTB was performed with sputum swabs and tongue swabs. Diagnostic accuracy was evaluated against a sputum-culture-based reference and as compared with sputum-smear microscopy and Xpert MTB/RIF Ultra assay. Usability was assessed with a system usability scale and direct observation.ResultsA total of 1380 participants were enrolled; 255 (18.5%) had human immunodeficiency virus infection and 226 (16.4%) had culture-confirmed tuberculosis. MiniDock MTB sensitivity was 85.7% (95% confidence interval [CI], 80.4 to 90.0) with sputum and 79.6% (95% CI, 73.8 to 84.7) with tongue swabs; specificity was greater than 97.5% for both. Results of sputum tests with MiniDock MTB closely matched those with Xpert MTB/RIF Ultra for sensitivity (difference, -2.8 percentage points; 95% CI, -6.0 to 0.5). MiniDock MTB had greater sensitivity than smear microscopy for tests of sputum (difference, 24.3 percentage points; 95% CI, 17.9 to 30.7) and tongue swabs (difference, 18.3 percentage points; 95% CI, 12.0 to 24.7). The test showed diagnostic accuracy that was consistent with World Health Organization (WHO) accuracy targets for near-point-of-care tuberculosis diagnostics (≥85% sensitivity for sputum and ≥75% for nonsputum and ≥98% specificity for both). The median score on the system usability scale (range, 0 to 100, with higher scores indicating better perceived usability) was 75 (interquartile range, 65 to 80), which indicated good usability. No adverse events related to the index test were reported.ConclusionsMiniDock MTB met WHO targets for diagnostic accuracy and usability for tuberculosis detection across diverse clinical settings. (Funded by the National Institutes of Health and others; Rapid Research in Diagnostics Development for TB Network and Assessing Diagnostics at Point-of-Care for Tuberculosis ClinicalTrials.gov numbers, NCT04923958 and NCT05941052.).