Large-scale phenotyping of patients with long COVID post-hospitalization reveals mechanistic subtypes of disease.

One in ten severe acute respiratory syndrome coronavirus 2 infections result in prolonged symptoms termed long coronavirus disease (COVID), yet disease phenotypes and mechanisms are poorly understood1. Here we profiled 368 plasma proteins in 657 participants ≥3 months following hospitalization. Of these, 426 had at least one long COVID symptom and 233 had fully recovered. Elevated markers of myeloid inflammation and complement activation were associated with long COVID. IL-1R2, MATN2 and COLEC12 were associated with cardiorespiratory symptoms, fatigue and anxiety/depression; MATN2, CSF3 and C1QA were elevated in gastrointestinal symptoms and C1QA was elevated in cognitive impairment. Additional markers of alterations in nerve tissue repair (SPON-1 and NFASC) were elevated in those with cognitive impairment and SCG3, suggestive of brain-gut axis disturbance, was elevated in gastrointestinal symptoms. Severe acute respiratory syndrome coronavirus 2-specific immunoglobulin G (IgG) was persistently elevated in some individuals with long COVID, but virus was not detected in sputum. Analysis of inflammatory markers in nasal fluids showed no association with symptoms. Our study aimed to understand inflammatory processes that underlie long COVID and was not designed for biomarker discovery. Our findings suggest that specific inflammatory pathways related to tissue damage are implicated in subtypes of long COVID, which might be targeted in future therapeutic trials.

Defining the Role of Cellular Immune Signatures in Diagnostic Evaluation of Suspected Tuberculosis.

BACKGROUND: Diagnosis of paucibacillary tuberculosis (TB) including extrapulmonary TB is a significant challenge, particularly in high-income, low-incidence settings. Measurement of Mycobacterium tuberculosis (Mtb)-specific cellular immune signatures by flow cytometry discriminates active TB from latent TB infection (LTBI) in case-control studies; however, their diagnostic accuracy and clinical utility in routine clinical practice is unknown. METHODS: Using a nested case-control study design within a prospective multicenter cohort of patients presenting with suspected TB in England, we assessed diagnostic accuracy of signatures in 134 patients who tested interferon-gamma release assay (IGRA)-positive and had final diagnoses of TB or non-TB diseases with coincident LTBI. Cellular signatures were measured using flow cytometry. RESULTS: All signatures performed less well than previously reported. Only signatures incorporating measurement of phenotypic markers on functional Mtb-specific CD4 T cells discriminated active TB from non-TB diseases with LTBI. The signatures measuring HLA-DR+IFNγ + CD4 T cells and CD45RA-CCR7-CD127- IFNγ -IL-2-TNFα + CD4 T cells performed best with 95% positive predictive value (95% confidence interval, 90-97) in the clinically challenging subpopulation of IGRA-positive but acid-fast bacillus (AFB) smear-negative TB suspects. CONCLUSIONS: Two cellular immune signatures could improve and accelerate diagnosis in the challenging group of patients who are IGRA-positive, AFB smear-negative, and have paucibacillary TB.

Effect of CRTH2 antagonism on the response to experimental rhinovirus infection in asthma: a pilot randomised controlled trial.

BACKGROUND AND AIMS: The chemoattractant receptor-homologous molecule expressed on T helper type 2 cells (CRTH2) antagonist timapiprant improved lung function and asthma control in a phase 2 study, with evidence suggesting reduced exacerbations. We aimed to assess whether timapiprant attenuated or prevented asthma exacerbations induced by experimental rhinovirus (RV) infection. We furthermore hypothesised that timapiprant would dampen RV-induced type 2 inflammation and consequently improve antiviral immune responses. METHODS: Atopic patients with partially controlled asthma on maintenance inhaled corticosteroids were randomised to timapiprant (n=22) or placebo (n=22) and challenged with RV-A16 3 weeks later. The primary endpoint was the cumulative lower respiratory symptom score over the 14 days post infection. Upper respiratory symptoms, spirometry, airway hyperresponsiveness, exhaled nitric oxide, RV-A16 virus load and soluble mediators in upper and lower airways samples, and CRTH2 staining in bronchial biopsies were additionally assessed before and during RV-A16 infection. RESULTS: Six subjects discontinued the study and eight were not infected; outcomes were assessed in 16 timapiprant-treated and 14 placebo-treated, successfully infected subjects. There were no differences between treatment groups in clinical exacerbation severity including cumulative lower respiratory symptom score day 0-14 (difference 3.0 (95% CI -29.0 to 17.0), p=0.78), virus load, antiviral immune responses, or RV-A16-induced airway inflammation other than in the bronchial biopsies, where CRTH2 staining was increased during RV-A16 infection in the placebo-treated but not the timapiprant-treated group. Timapiprant had a favourable safety profile, with no deaths, serious adverse events or drug-related withdrawals. CONCLUSION: Timapiprant treatment had little impact on the clinicopathological changes induced by RV-A16 infection in partially controlled asthma.

Broadening symptom criteria improves early case identification in SARS-CoV-2 contacts.

BACKGROUND: The success of case isolation and contact tracing for the control of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission depends on the accuracy and speed of case identification. We assessed whether inclusion of additional symptoms alongside three canonical symptoms (CS), i.e. fever, cough and loss or change in smell or taste, could improve case definitions and accelerate case identification in SARS-CoV-2 contacts. METHODS: Two prospective longitudinal London (UK)-based cohorts of community SARS-CoV-2 contacts, recruited within 5 days of exposure, provided independent training and test datasets. Infected and uninfected contacts completed daily symptom diaries from the earliest possible time-points. Diagnostic information gained by adding symptoms to the CS was quantified using likelihood ratios and area under the receiver operating characteristic curve. Improvements in sensitivity and time to detection were compared with penalties in terms of specificity and number needed to test. RESULTS: Of 529 contacts within two cohorts, 164 (31%) developed PCR-confirmed infection and 365 (69%) remained uninfected. In the training dataset (n=168), 29% of infected contacts did not report the CS. Four symptoms (sore throat, muscle aches, headache and appetite loss) were identified as early-predictors (EP) which added diagnostic value to the CS. The broadened symptom criterion "≥1 of the CS, or ≥2 of the EP" identified PCR-positive contacts in the test dataset on average 2 days earlier after exposure (p=0.07) than "≥1 of the CS", with only modest reduction in specificity (5.7%). CONCLUSIONS: Broadening symptom criteria to include individuals with at least two of muscle aches, headache, appetite loss and sore throat identifies more infections and reduces time to detection, providing greater opportunities to prevent SARS-CoV-2 transmission.

Evaluating the clinical impact of routine whole genome sequencing in tuberculosis treatment decisions and the issue of isoniazid mono-resistance.

BACKGROUND: The UK has implemented routine use of whole genome sequencing (WGS) in TB diagnostics. The WHO recommends addition of a fluoroquinolone for isoniazid mono-resistance, so early detection may be of use. The aim of this study was to describe the clinical utility and impact of WGS on treatment decisions for TB in a low incidence high resource clinical setting. The clinical turnaround time (TAT) for WGS was analysed in comparison to TB PCR using Xpert MTB/RIF (Cepheid, Sunnyvale, CA) results where available and subsequent phenotypic drug susceptibility testing (DST) when required. METHODS: This was a retrospective analysis of TB cases from January 2018 to March 2019 in London. Susceptibility and TAT by WGS, phenotypic DST, TB PCR using Xpert MTB/RIF were correlated to drug changes in order to describe the utility of WGS on treatment decisions on isoniazid mono-resistance in a low incidence high resource setting. RESULTS: 189 TB cases were identified; median age 44 years (IQR 28-60), m:f ratio 112:77, 7 with HIV and 6 with previous TB. 80/189 cases had a positive culture and WGS result. 50/80 were fully sensitive to 1st line treatment on WGS, and the rest required additional DST. 20/80 cases required drug changes; 12 were defined by WGS: 8 cases had isoniazid mono-resistance, 2 had MDR-TB, 1 had isoniazid and pyrazinamide resistance and 1 had ethambutol resistance. The median TAT for positive culture was 16 days (IQR 12.5-20.5); for WGS was 35 days (IQR 29.5-38.75) and for subsequent DST was 86 days (IQR 69.5-96.75), resulting in non-WHO regimens for a median of 50.5 days (IQR 28.0-65.0). 9/12 has TB PCRs (Xpert MTB/RIF), with a median TAT of 1 day. CONCLUSION: WGS clearly has a substantial role in our routine UK clinical settings with faster turnaround times in comparison to phenotypic DST. However, the majority of treatment changes defined by WGS were related to isoniazid resistance and given the 1 month TAT for WGS, it would be preferable to identify isoniazid resistance more quickly. Therefore if resources allow, diagnostic pathways should be optimised by parallel use of WGS and new molecular tests to rapidly identify isoniazid resistance in addition to rifampicin resistance and to minimise delays in starting WHO isoniazid resistance treatment.

Innate-like Gene Expression of Lung-Resident Memory CD8+ T Cells during Experimental Human Influenza: A Clinical Study.

Rationale: Suboptimal vaccine immunogenicity and antigenic mismatch, compounded by poor uptake, means that influenza remains a major global disease. T cells recognizing peptides derived from conserved viral proteins could enhance vaccine-induced cross-strain protection. Objectives: To investigate the kinetics, phenotypes, and function of influenza virus-specific CD8+ resident memory T (Trm) cells in the lower airway and infer the molecular pathways associated with their response to infection in vivo. Methods: Healthy volunteers, aged 18-55, were inoculated intranasally with influenza A/California/4/09(H1N1). Blood, upper airway, and (in a subgroup) lower airway samples were obtained throughout infection. Symptoms were assessed by using self-reported diaries, and the nasal viral load was assessed by using quantitative PCR. T-cell responses were analyzed by using a three-color FluoroSpot assay, flow cytometry with MHC I-peptide tetramers, and RNA sequencing, with candidate markers being confirmed by using the immunohistochemistry results for endobronchial biopsy specimens. Measurements and Main Results: After challenge, 57% of participants became infected. Preexisting influenza-specific CD8+ T cells in blood correlated strongly with a reduced viral load, which peaked at Day 3. Influenza-specific CD8+ T cells in BAL fluid were highly enriched and predominantly expressed the Trm markers CD69 and CD103. Comparison between preinfection CD8+ T cells in BAL fluid and blood by using RNA sequencing revealed 3,928 differentially expressed genes, including all major Trm-cell markers. However, gene set enrichment analysis of BAL-fluid CD8+ T cells showed primarily innate cell-related pathways and, during infection, included upregulation of innate chemokines (Cxcl1, Cxcl10, and Cxcl16) that were also expressed by CD8+ cells in bronchial tissues. Conclusions: CD8+ Trm cells in the human lung display innate-like gene and protein expression that demonstrates blurred divisions between innate and adaptive immunity. Clinical study registered with www.clinicaltrials.gov (NCT02755948).

Pulmonary Innate Lymphoid Cell Responses during Rhinovirus-induced Asthma Exacerbations In Vivo: A Clinical Trial.

Rationale: Type 2 innate lymphoid cells (ILC2s) are significant sources of type 2 cytokines, which are implicated in the pathogenesis of asthma and asthma exacerbations. The role of ILC2s in virus-induced asthma exacerbations is not well characterized. Objectives: To characterize pulmonary ILC responses following experimental rhinovirus challenge in patients with moderate asthma and healthy subjects. Methods: Patients with moderate asthma and healthy subjects were inoculated with rhinovirus-16 and underwent bronchoscopy at baseline and at Day 3, and Day 8 after inoculation. Pulmonary ILC1s and ILC2s were quantified in bronchoalveolar lavage using flow cytometry. The ratio of bronchoalveolar lavage ILC2:ILC1 was assessed to determine their relative contributions to the clinical and immune response to rhinovirus challenge. Measurements and Main Results: At baseline, ILC2s were significantly higher in patients with asthma than in healthy subjects. At Day 8, ILC2s significantly increased from baseline in both groups, which was significantly higher in patients with asthma than in healthy subjects (all comparisons P < 0.05). In healthy subjects, ILC1s increased from baseline at Day 3 (P = 0.001), while in patients with asthma, ILC1s increased from baseline at Day 8 (P = 0.042). Patients with asthma had significantly higher ILC2:ILC1 ratios at baseline (P = 0.024) and Day 8 (P = 0.005). Increased ILC2:ILC1 ratio in patients with asthma correlated with clinical exacerbation severity and type 2 cytokines in nasal mucosal lining fluid. Conclusions: An ILC2-predominant inflammatory profile in patients with asthma was associated with increased severity and duration of rhinovirus infection compared with healthy subjects, supporting the potential role of ILC2s in the pathogenesis of virus-induced asthma exacerbations.

Patterns of myocardial injury in recovered troponin-positive COVID-19 patients assessed by cardiovascular magnetic resonance.

BACKGROUND: Troponin elevation is common in hospitalized COVID-19 patients, but underlying aetiologies are ill-defined. We used multi-parametric cardiovascular magnetic resonance (CMR) to assess myocardial injury in recovered COVID-19 patients. METHODS AND RESULTS: One hundred and forty-eight patients (64 ± 12 years, 70% male) with severe COVID-19 infection [all requiring hospital admission, 48 (32%) requiring ventilatory support] and troponin elevation discharged from six hospitals underwent convalescent CMR (including adenosine stress perfusion if indicated) at median 68 days. Left ventricular (LV) function was normal in 89% (ejection fraction 67% ± 11%). Late gadolinium enhancement and/or ischaemia was found in 54% (80/148). This comprised myocarditis-like scar in 26% (39/148), infarction and/or ischaemia in 22% (32/148) and dual pathology in 6% (9/148). Myocarditis-like injury was limited to three or less myocardial segments in 88% (35/40) of cases with no associated LV dysfunction; of these, 30% had active myocarditis. Myocardial infarction was found in 19% (28/148) and inducible ischaemia in 26% (20/76) of those undergoing stress perfusion (including 7 with both infarction and ischaemia). Of patients with ischaemic injury pattern, 66% (27/41) had no past history of coronary disease. There was no evidence of diffuse fibrosis or oedema in the remote myocardium (T1: COVID-19 patients 1033 ± 41 ms vs. matched controls 1028 ± 35 ms; T2: COVID-19 46 ± 3 ms vs. matched controls 47 ± 3 ms). CONCLUSIONS: During convalescence after severe COVID-19 infection with troponin elevation, myocarditis-like injury can be encountered, with limited extent and minimal functional consequence. In a proportion of patients, there is evidence of possible ongoing localized inflammation. A quarter of patients had ischaemic heart disease, of which two-thirds had no previous history. Whether these observed findings represent pre-existing clinically silent disease or de novo COVID-19-related changes remain undetermined. Diffuse oedema or fibrosis was not detected.

Increased nasal mucosal interferon and CCL13 response to a TLR7/8 agonist in asthma and allergic rhinitis.

BACKGROUND: Acute respiratory viral infections are a major cause of respiratory morbidity and mortality, especially in patients with preexisting lung diseases such as asthma. Toll-like receptors are critical in the early detection of viruses and in activating innate immunity in the respiratory mucosa, but there is no reliable and convenient method by which respiratory mucosal innate immune responses can be measured. OBJECTIVE: We sought to assess in vivo immune responses to an innate stimulus and compare responsiveness between healthy volunteers and volunteers with allergy. METHODS: We administered the Toll-like receptor 7/8 agonist resiquimod (R848; a synthetic analogue of single-stranded RNA) or saline by nasal spray to healthy participants without allergy (n = 12), those with allergic rhinitis (n = 12), or those with allergic rhinitis with asthma (n = 11). Immune mediators in blood and nasal fluid and mucosal gene expression were monitored over time. RESULTS: R848 was well tolerated and significantly induced IFN-α2a, IFN-γ, proinflammatory cytokines (TNF-α, IL-2, IL-12p70), and chemokines (CXCL10, C-C motif chemokine ligand [CCL]2, CCL3, CCL4, and CCL13) in nasal mucosal fluid, without causing systemic immune activation. Participants with allergic rhinitis or allergic rhinitis with asthma had increased IFN-α2a, CCL3, and CCL13 responses relative to healthy participants; those with asthma had increased induction of IFN-stimulated genes DExD/H-box helicase 58, MX dynamin-like GTPase 1, and IFN-induced protein with tetratricopeptide repeats 3. CONCLUSIONS: Responses to nasal delivery of R848 enables simple assessment of mucosal innate responsiveness, revealing that patients with allergic disorders have an increased nasal mucosal IFN and chemokine response to the viral RNA analogue R848. This highlights that dysregulated innate immune responses of the nasal mucosa in allergic individuals may be important in determining the outcome of viral exposure.

Collaborative Ocular Tuberculosis Study Consensus Guidelines on the Management of Tubercular Uveitis-Report 1: Guidelines for Initiating Antitubercular Therapy in Tubercular Choroiditis.

TOPIC: An international, expert-led consensus initiative organized by the Collaborative Ocular Tuberculosis Study (COTS), along with the International Ocular Inflammation Society and the International Uveitis Study Group, systematically developed evidence- and experience-based recommendations for the treatment of tubercular choroiditis. CLINICAL RELEVANCE: The diagnosis and management of tubercular uveitis (TBU) pose a significant challenge. Current guidelines and literature are insufficient to guide physicians regarding the initiation of antitubercular therapy (ATT) in patients with TBU. METHODS: An international expert steering subcommittee of the COTS group identified clinical questions and conducted a systematic review of the published literature on the use of ATT for tubercular choroiditis. Using an interactive online questionnaire, guided by background knowledge from published literature, 81 global experts (including ophthalmologists, pulmonologists, and infectious disease physicians) generated preliminary consensus statements for initiating ATT in tubercular choroiditis, using Oxford levels of medical evidence. In total, 162 statements were identified regarding when to initiate ATT in patients with tubercular serpiginous-like choroiditis, tuberculoma, and tubercular focal or multifocal choroiditis. The COTS group members met in November 2018 to refine these statements by a 2-step modified Delphi process. RESULTS: Seventy consensus statements addressed the initiation of ATT in the 3 subtypes of tubercular choroiditis, and in addition, 10 consensus statements were developed regarding the use of adjunctive therapy in tubercular choroiditis. Experts agreed on initiating ATT in tubercular choroiditis in the presence of positive results for any 1 of the positive immunologic tests along with radiologic features suggestive of tuberculosis. For tubercular serpiginous-like choroiditis and tuberculoma, positive results from even 1 positive immunologic test were considered sufficient to recommend ATT, even if there were no radiologic features suggestive of tuberculosis. DISCUSSION: Consensus guidelines were developed to guide the initiation of ATT in patients with tubercular choroiditis, based on the published literature, expert opinion, and practical experience, to bridge the gap between clinical need and available medical evidence.

Collaborative Ocular Tuberculosis Study Consensus Guidelines on the Management of Tubercular Uveitis-Report 2: Guidelines for Initiating Antitubercular Therapy in Anterior Uveitis, Intermediate Uveitis, Panuveitis, and Retinal Vasculitis.

TOPIC: The Collaborative Ocular Tuberculosis Study (COTS), supported by the International Ocular Inflammation Society, International Uveitis Study Group, and Foster Ocular Immunological Society, set up an international, expert-led consensus project to develop evidence- and experience-based guidelines for the management of tubercular uveitis (TBU). CLINICAL RELEVANCE: The absence of international agreement on the use of antitubercular therapy (ATT) in patients with TBU contributes to a significant heterogeneity in the approach to the management of this condition. METHODS: Consensus statements for the initiation of ATT in TBU were generated using a 2-step modified Delphi technique. In Delphi step 1, a smart web-based survey based on background evidence from published literature was prepared to collect the opinion of 81 international experts on the use of ATT in different clinical scenarios. The survey included 324 questions related to tubercular anterior uveitis (TAU), tubercular intermediate uveitis (TIU), tubercular panuveitis (TPU), and tubercular retinal vasculitis (TRV) administered by the experts, after which the COTS group met in November 2019 for a systematic and critical discussion of the statements in accordance with the second round of the modified Delphi process. RESULTS: Forty-four consensus statements on the initiation of ATT in TAU, TIU, TPU, and TRV were obtained, based on ocular phenotypes suggestive of TBU and corroborative evidence of tuberculosis, provided by several combinations of immunologic and radiologic test results. Experts agreed on initiating ATT in recurrent TAU, TIU, TPU, and active TRV depending on the TB endemicity. In the presence of positive results for any 1 of the immunologic tests along with radiologic features suggestive of past evidence of tuberculosis infection. In patients with a first episode of TAU, consensus to initiate ATT was reached only if both immunologic and radiologic test results were positive. DISCUSSION: The COTS consensus guidelines were generated based on the evidence from published literature, specialists' opinions, and logic construction to address the initiation of ATT in TBU. The guidelines also should inform public policy by adding specific types of TBU to the list of conditions that should be treated as tuberculosis.

Diabetes mellitus and latent tuberculosis infection: baseline analysis of a large UK cohort.

We conducted a cross-sectional analysis of baseline data from a UK cohort study which enrolled participants at risk of latent tuberculosis infection (LTBI, defined as a positive result for either of the two interferon gamma release assays). Binomial regression with a log link was used to estimate crude and adjusted prevalence ratios (PRs) and 95% CIs for the relationship between diabetes mellitus (DM) and LTBI. Adjusted for age, sex, ethnicity, body mass index and the presence of other immunocompromising conditions, DM was associated with a 15% higher prevalence of LTBI (adjusted PR=1.15, 95% CI 1.02 to 1.30, p=0.025). TRIAL REGISTRATION NUMBER: PREDICT is registered on clinicaltrials.gov (NCT01162265).

Patterns of systemic and local inflammation in patients with asthma hospitalised with influenza.

BACKGROUND: Patients with asthma are at risk of hospitalisation with influenza, but the reasons for this predisposition are unknown. STUDY SETTING: A prospective observational study of adults with PCR-confirmed influenza in 11 UK hospitals, measuring nasal, nasopharyngeal and systemic immune mediators and whole-blood gene expression. RESULTS: Of 133 admissions, 40 (30%) had previous asthma; these were more often female (70% versus 38.7%, OR 3.69, 95% CI 1.67-8.18; p=0.0012), required less mechanical ventilation (15% versus 37.6%, Chi-squared 6.78; p=0.0338) and had shorter hospital stays (mean 8.3 versus 15.3 days, p=0.0333) than those without. In patients without asthma, severe outcomes were more frequent in those given corticosteroids (OR 2.63, 95% CI 1.02-6.96; p=0.0466) or presenting >4 days after disease onset (OR 5.49, 95% CI 2.28-14.03; p=0.0002). Influenza vaccination in at-risk groups (including asthma) were lower than intended by national policy and the early use of antiviral medications were less than optimal. Mucosal immune responses were equivalent between groups. Those with asthma had higher serum interferon (IFN)-α, but lower serum tumour necrosis factor, interleukin (IL)-5, IL-6, CXCL8, CXCL9, IL-10, IL-17 and CCL2 levels (all p<0.05); both groups had similar serum IL-13, total IgE, periostin and blood eosinophil gene expression levels. Asthma diagnosis was unrelated to viral load, IFN-α, IFN-γ, IL-5 or IL-13 levels. CONCLUSIONS: Asthma is common in those hospitalised with influenza, but may not represent classical type 2-driven disease. Those admitted with influenza tend to be female with mild serum inflammatory responses, increased serum IFN-α levels and good clinical outcomes.

Fluoroquinolones and isoniazid-resistant tuberculosis: implications for the 2018 WHO guidance.

INTRODUCTION: 2018 World Health Organization (WHO) guidelines for the treatment of isoniazid (H)-resistant (Hr) tuberculosis recommend a four-drug regimen: rifampicin (R), ethambutol (E), pyrazinamide (Z) and levofloxacin (Lfx), with or without H ([H]RZE-Lfx). This is used once Hr is known, such that patients complete 6 months of Lfx (≥6[H]RZE-6Lfx). This cohort study assessed the impact of fluoroquinolones (Fq) on treatment effectiveness, accounting for Hr mutations and degree of phenotypic resistance. METHODS: This was a retrospective cohort study of 626 Hr tuberculosis patients notified in London, 2009-2013. Regimens were described and logistic regression undertaken of the association between regimen and negative regimen-specific outcomes (broadly, death due to tuberculosis, treatment failure or disease recurrence). RESULTS: Of 594 individuals with regimen information, 330 (55.6%) were treated with (H)RfZE (Rf=rifamycins) and 211 (35.5%) with (H)RfZE-Fq. The median overall treatment period was 11.9 months and median Z duration 2.1 months. In a univariable logistic regression model comparing (H)RfZE with and without Fqs, there was no difference in the odds of a negative regimen-specific outcome (baseline (H)RfZE, cluster-specific odds ratio 1.05 (95% CI 0.60-1.82), p=0.87; cluster NHS trust). Results varied minimally in a multivariable model. This odds ratio dropped (0.57, 95% CI 0.14-2.28) when Hr genotype was included, but this analysis lacked power (p=0.42). CONCLUSIONS: In a high-income setting, we found a 12-month (H)RfZE regimen with a short Z duration to be similarly effective for Hr tuberculosis with or without a Fq. This regimen may result in fewer adverse events than the WHO recommendations.

Innate activation of human primary epithelial cells broadens the host response to Mycobacterium tuberculosis in the airways.

Early events in the human airways determining whether exposure to Mycobacterium tuberculosis (Mtb) results in acquisition of infection are poorly understood. Epithelial cells are the dominant cell type in the lungs, but little is known about their role in tuberculosis. We hypothesised that human primary airway epithelial cells are part of the first line of defense against Mtb-infection and contribute to the protective host response in the human respiratory tract. We modelled these early airway-interactions with human primary bronchial epithelial cells (PBECs) and alveolar macrophages. By combining in vitro infection and transwell co-culture models with a global transcriptomic approach, we identified PBECs to be inert to direct Mtb-infection, yet to be potent responders within an Mtb-activated immune network, mediated by IL1ß and type I interferon (IFN). Activation of PBECs by Mtb-infected alveolar macrophages and monocytes increased expression of known and novel antimycobacterial peptides, defensins and S100-family members and epithelial-myeloid interactions further shaped the immunological environment during Mtb-infection by promoting neutrophil influx. This is the first in depth analysis of the primary epithelial response to infection and offers new insights into their emerging role in tuberculosis through complementing and amplifying responses to Mtb.

Role of airway glucose in bacterial infections in patients with chronic obstructive pulmonary disease.

BACKGROUND: Patients with chronic obstructive pulmonary disease (COPD) have increased susceptibility to respiratory tract infection, which contributes to disease progression and mortality, but mechanisms of increased susceptibility to infection remain unclear. OBJECTIVES: The aim of this study was to determine whether glucose concentrations were increased in airway samples (nasal lavage fluid, sputum, and bronchoalveolar lavage fluid) from patients with stable COPD and to determine the effects of viral infection on sputum glucose concentrations and how airway glucose concentrations relate to bacterial infection. METHODS: We measured glucose concentrations in airway samples collected from patients with stable COPD and smokers and nonsmokers with normal lung function. Glucose concentrations were measured in patients with experimentally induced COPD exacerbations, and these results were validated in patients with naturally acquired COPD exacerbations. Relationships between sputum glucose concentrations, inflammatory markers, and bacterial load were examined. RESULTS: Sputum glucose concentrations were significantly higher in patients with stable COPD compared with those in control subjects without COPD. In both experimental virus-induced and naturally acquired COPD exacerbations, sputum and nasal lavage fluid glucose concentrations were increased over baseline values. There were significant correlations between sputum glucose concentrations and sputum inflammatory markers, viral load, and bacterial load. Airway samples with higher glucose concentrations supported more Pseudomonas aeruginosa growth in vitro. CONCLUSIONS: Airway glucose concentrations are increased in patients with stable COPD and further increased during COPD exacerbations. Increased airway glucose concentrations might contribute to bacterial infections in both patients with stable and those with exacerbated COPD. This has important implications for the development of nonantibiotic therapeutic strategies for the prevention or treatment of bacterial infection in patients with COPD.

Stratification of Latent Mycobacterium tuberculosis Infection by Cellular Immune Profiling.

Background: Recently acquired and remotely acquired latent Mycobacterium tuberculosis infection (LTBI) are clinically indistinguishable, yet recent acquisition of infection is the greatest risk factor for progression to tuberculosis in immunocompetent individuals. We aimed to evaluate the ability of cellular immune signatures that differ between active tuberculosis and LTBI to distinguish recently from remotely acquired LTBI. Methods: Fifty-nine individuals were recruited: 20 had active tuberculosis, 19 had recently acquired LTBI, and 20 had remotely acquired LTBI. The proportion of mycobacteria-specific CD4+ T cells secreting tumor necrosis factor α (TNF-α) but not interferon γ or interleukin 2 which had a differentiated effector phenotype (TNF-α-only TEFF), and the level of CD27 expression on IFN-γ-producing CD4+ T cells, were detected by flow cytometry. Results: The TNF-α-only TEFF signature was significantly higher in the group with recently acquired LTBI, compared with the group with remotely acquired LTBI (P < .0001), and it discriminated between these groups with high sensitivity and specificity, with an area under the curve of 0.87. Two signatures incorporating CD27 expression did not distinguish between recently and remotely acquired LTBI. Interestingly, the TNF-α-only TEFF signature in participants with recently acquired LTBI was more similar to that in participants with tuberculosis than that in participants with remotely acquired LTBI, suggesting that recently acquired LTBI is immunologically more similar to tuberculosis than remotely acquired LTBI. Conclusions: These findings reveal marked biological heterogeneity underlying the clinically homogeneous phenotype of LTBI, providing a rationale for immunological risk stratification to improve targeting of LTBI treatment.

Adverse Effects and Choice between the Injectable Agents Amikacin and Capreomycin in Multidrug-Resistant Tuberculosis.

The prolonged use of injectable agents in a regimen for the treatment of multidrug-resistant tuberculosis (MDR-TB) is recommended by the World Health Organization, despite its association with ototoxicity and nephrotoxicity. We undertook this study to look at the relative adverse effects of capreomycin and amikacin. We reviewed the case notes of 100 consecutive patients treated at four MDR-TB treatment centers in the United Kingdom. The median total duration of treatment with an injectable agent was 178 days (interquartile range [IQR], 109 to 192 days; n = 73) for those with MDR-TB, 179 days (IQR, 104 to 192 days; n = 12) for those with MDR-TB plus fluoroquinolone resistance, and 558 days (IQR, 324 to 735 days; n = 8) for those with extensively drug-resistant tuberculosis (XDR-TB). Injectable use was longer for those started with capreomycin (183 days; IQR, 123 to 197 days) than those started with amikacin (119 days; IQR, 83 to 177 days) (P = 0.002). Excluding patients with XDR-TB, 51 of 85 (60%) patients were treated with an injectable for over 6 months and 12 of 85 (14%) were treated with an injectable for over 8 months. Forty percent of all patients discontinued the injectable due to hearing loss. Fifty-five percent of patients experienced ototoxicity, which was 5 times (hazard ratio [HR], 5.2; 95% confidence interval [CI], 1.2 to 22.6; P = 0.03) more likely to occur in those started on amikacin than in those treated with capreomycin only. Amikacin was associated with less hypokalemia than capreomycin (odds ratio, 0.28; 95% CI, 0.11 to 0.72), with 5 of 37 (14%) patients stopping capreomycin due to recurrent electrolyte loss. There was no difference in the number of patients experiencing a rise in the creatinine level of >1.5 times the baseline level. Hearing loss is frequent in this cohort, though its incidence is significantly lower in those starting capreomycin, which should be given greater consideration as a first-line agent.

Drug-induced liver injury from antituberculous treatment: a retrospective study from a large TB centre in the UK.

BACKGROUND: We describe drug-induced liver injury (DILI) secondary to antituberculous treatment (ATT) in a large tuberculosis (TB) centre in London; we identify the proportion who had risk factors for DILI and the timing and outcome of DILI. METHODS: We identified consecutive patients who developed DILI whilst on treatment for active TB; patients with active TB without DILI were selected as controls. Comprehensive demographic and clinical data, management and outcome were recorded. RESULTS: There were 105 (6.9%) cases of ATT-associated DILI amongst 1529 patients diagnosed with active TB between April 2010 and May 2014. Risk factors for DILI were: low patient weight, HIV-1 co-infection, higher baseline ALP, and alcohol intake. Only 25.7% of patients had British or American Thoracic Society defined criteria for liver test (LT) monitoring. Half (53%) of the cases occurred within 2 weeks of starting ATT and 87.6% occurred within 8 weeks. Five (4.8%) of seven deaths were attributable to DILI. CONCLUSIONS: Only a quarter of patients who developed DILI had British or American Thoracic Society defined criteria for pre-emptive LT monitoring, suggesting that all patients on ATT should be considered for universal liver monitoring particularly during the first 8 weeks of treatment.

Increased nuclear suppressor of cytokine signaling 1 in asthmatic bronchial epithelium suppresses rhinovirus induction of innate interferons.

BACKGROUND: Rhinovirus infections are the dominant cause of asthma exacerbations, and deficient virus induction of IFN-α/ß/λ in asthmatic patients is important in asthma exacerbation pathogenesis. Mechanisms causing this interferon deficiency in asthmatic patients are unknown. OBJECTIVE: We sought to investigate the expression of suppressor of cytokine signaling (SOCS) 1 in tissues from asthmatic patients and its possible role in impaired virus-induced interferon induction in these patients. METHODS: We assessed SOCS1 mRNA and protein levels in vitro, bronchial biopsy specimens, and mice. The role of SOCS1 was inferred by proof-of-concept studies using overexpression with reporter genes and SOCS1-deficient mice. A nuclear role of SOCS1 was shown by using bronchial biopsy staining, overexpression of mutant SOCS1 constructs, and confocal microscopy. SOCS1 levels were also correlated with asthma-related clinical outcomes. RESULTS: We report induction of SOCS1 in bronchial epithelial cells (BECs) by asthma exacerbation-related cytokines and by rhinovirus infection in vitro. We found that SOCS1 was increased in vivo in bronchial epithelium and related to asthma severity. SOCS1 expression was also increased in primary BECs from asthmatic patients ex vivo and was related to interferon deficiency and increased viral replication. In primary human epithelium, mouse lung macrophages, and SOCS1-deficient mice, SOCS1 suppressed rhinovirus induction of interferons. Suppression of virus-induced interferon levels was dependent on SOCS1 nuclear translocation but independent of proteasomal degradation of transcription factors. Nuclear SOCS1 levels were also increased in BECs from asthmatic patients. CONCLUSION: We describe a novel mechanism explaining interferon deficiency in asthmatic patients through a novel nuclear function of SOCS1 and identify SOCS1 as an important therapeutic target for asthma exacerbations.