Improving 1-Year Mortality Following Intensive Care Unit Admission in Adults with HIV: A 20-Year Observational Study.

BACKGROUND: Despite widespread use of combination antiretroviral therapy, people with HIV (PWH) continue to have an increased risk of admission to and mortality in the intensive care unit (ICU). Mortality risk after hospital discharge is not well described. Using retrospective data on adult PWH (≥18 years) admitted to ICU from 2000-2019 in an HIV-referral centre, we describe trends in 1-year mortality after ICU admission. METHODS: One-year mortality was calculated from index ICU admission to date of death; with follow-up right-censored at day 365 for people remaining alive at 1 year, or day 7 after ICU discharge if lost-to-follow-up after hospital discharge. Cox regression was used to describe the association with calendar year before and after adjustment for patient characteristics (age, sex, Acute Physiology and Chronic Health Evaluation II [APACHE II] score, CD4+ T-cell count, and recent HIV diagnosis) at ICU admission. Analyses were additionally restricted to those discharged alive from ICU using a left-truncated design, with further adjustment for respiratory failure at ICU admission in these analyses. RESULTS: Two hundred and twenty-one PWH were admitted to ICU (72% male, median [interquartile range] age 45 [38-53] years) of whom 108 died within 1-year (cumulative 1-year survival: 50%). Overall, the hazard of 1-year mortality was decreased by 10% per year (crude hazard ratio (HR): 0.90 (95% confidence interval: 0.87-0.93)); the association was reduced to 7% per year (adjusted HR: 0.93 (0.89-0.98)) after adjustment. Conclusions were similar among the subset of 136 patients discharged alive (unadjusted: 0.91 (0.84-0.98); adjusted 0.92 (0.84, 1.02)). CONCLUSIONS: Between 2000 and 2019, 1-year mortality after ICU admission declined at this ICU. Our findings highlight the need for multi-centre studies and the importance of continued engagement in care after hospital discharge among PWH.

Forgiveness Is the Attribute of the Strong: Nonadherence and Regimen Shortening in Drug-sensitive Tuberculosis.

Rationale: "Forgiveness" charts the ability of a drug or regimen to withstand nonadherence without negative clinical consequences. Objectives: We aimed to determine the influence of regimen length, regimen drugs, and dosing, and when during treatment nonadherence occurs on the forgiveness of antituberculosis regimens. Methods: Using data from three randomized controlled trials comparing experimental 4-month regimens for drug-sensitive tuberculosis with the standard 6-month regimen, we used generalized linear models to examine how the risk of a negative composite outcome changed as dose-taking decreased. The percentage of doses taken and the absolute number of doses missed were calculated during the intensive and continuation phases of treatment, and overall. A mediation analysis was undertaken to determine how much the association between intensive phase dose-taking and the negative composite outcome was mediated through continuation phase dose-taking. Measurements and Main Results: Forgiveness of the 4- and 6-month regimens did not differ for any treatment period. Importantly, 4-month regimens were no less forgiving of small numbers of absolute missed doses than the 6-month regimen (e.g., for 3-7 missed doses vs. no missed doses [baseline], 6-month regimen adjusted risk ratio 1.65 [95% confidence interval, 0.80-3.41] and 4-month regimens 1.80 [1.33-2.45]). No 4-month regimen was conclusively more forgiving than another. We found evidence of mediation by continuation phase dose-taking on the intensive phase dose-taking and negative composite outcome relationship. Conclusions: With the current appetite for, and progress toward, shorter drug-sensitive tuberculosis regimens worldwide, we offer reassurance that shorter regimens are not necessarily less forgiving of nonadherence. Given the importance of continuation phase adherence, patient support during this period should not be neglected.

Estimating the risk of mortality attributable to recent late HIV diagnosis following admission to the intensive care unit: A single-centre observational cohort study.

OBJECTIVES: Despite improvements in survival of people with HIV admitted to the intensive care unit (ICU), late diagnosis continues to contribute to in-ICU mortality. We quantify the population attributable fraction (PAF) of in-ICU mortality for recent late diagnosis among people with HIV admitted to a London ICU. METHODS: Index ICU admissions among people with HIV were considered from 2000 to 2019. Recent late diagnosis was a CD4 T-cell count < 350 cells/µL and/or AIDS-defining illness at/within 6 months prior to ICU admission. Univariate comparisons were conducted using Wilcoxon rank-sum/Cochran-Armitage/χ2 /Fisher's exact tests. We used Poisson regression (robust standard errors) to estimate unadjusted/adjusted (age, sex, calendar year of ICU admission) risk ratios (RRs) and regression standardization to estimate the PAF. RESULTS: In all, 207 index admissions were included [median (interquartile range) age: 46 (38-53) years; 72% male]; 58 (28%) had a recent late diagnosis, all of whom had a CD4 count < 350 cells/µL, and 95% had advanced HIV (CD4 count < 200 cells/µL and/or AIDS at admission) as compared with 57% of those who did not have a recent late diagnosis (p < 0.001). In-ICU mortality was 27% (55/207); 38% versus 22% in those who did and did not have a recent late diagnosis, respectively (p = 0.02). Recent late diagnosis was independently associated with increased in-ICU mortality risk (adjusted RR = 1.75) (95% confidence interval: 1.05-2.91), with 17.08% (16.04-18.12%) of deaths being attributable to this. CONCLUSIONS: There is a need for improved public health efforts focused on HIV testing and reporting of late diagnosis to better understand potentially missed opportunities for earlier HIV diagnosis in healthcare services.

Comparative assessment of viral dynamic models for SARS-CoV-2 for pharmacodynamic assessment in early treatment trials.

Pharmacometric analyses of time series viral load data may detect drug effects with greater power than approaches using single time points. Because SARS-CoV-2 viral load rapidly rises and then falls, viral dynamic models have been used. We compared different modelling approaches when analysing Phase II-type viral dynamic data. Using two SARS-CoV-2 datasets of viral load starting within 7 days of symptoms, we fitted the slope-intercept exponential decay (SI), reduced target cell limited (rTCL), target cell limited (TCL) and TCL with eclipse phase (TCLE) models using nlmixr. Model performance was assessed via Bayesian information criterion (BIC), visual predictive checks (VPCs), goodness-of-fit plots, and parameter precision. The most complex (TCLE) model had the highest BIC for both datasets. The estimated viral decline rate was similar for all models except the TCL model for dataset A with a higher rate (median [range] day-1 : dataset A; 0.63 [0.56-1.84]; dataset B: 0.81 [0.74-0.85]). Our findings suggest simple models should be considered during pharmacodynamic model development.

'Long-COVID': a cross-sectional study of persisting symptoms, biomarker and imaging abnormalities following hospitalisation for COVID-19.

Large numbers of people are being discharged from hospital following COVID-19 without assessment of recovery. In 384 patients (mean age 59.9 years; 62% male) followed a median 54 days post discharge, 53% reported persistent breathlessness, 34% cough and 69% fatigue. 14.6% had depression. In those discharged with elevated biomarkers, 30.1% and 9.5% had persistently elevated d-dimer and C reactive protein, respectively. 38% of chest radiographs remained abnormal with 9% deteriorating. Systematic follow-up after hospitalisation with COVID-19 identifies the trajectory of physical and psychological symptom burden, recovery of blood biomarkers and imaging which could be used to inform the need for rehabilitation and/or further investigation.

Blood Transcriptomic Stratification of Short-term Risk in Contacts of Tuberculosis.

BACKGROUND: The highest risk of tuberculosis arises in the first few months after exposure. We reasoned that this risk reflects incipient disease among tuberculosis contacts. Blood transcriptional biomarkers of tuberculosis may predate clinical diagnosis, suggesting they offer improved sensitivity to detect subclinical incipient disease. Therefore, we sought to test the hypothesis that refined blood transcriptional biomarkers of active tuberculosis will improve stratification of short-term disease risk in tuberculosis contacts. METHODS: We combined analysis of previously published blood transcriptomic data with new data from a prospective human immunodeficiency virus (HIV)-negative UK cohort of 333 tuberculosis contacts. We used stability selection as an alternative computational approach to identify an optimal signature for short-term risk of active tuberculosis and evaluated its predictive value in independent cohorts. RESULTS: In a previously published HIV-negative South African case-control study of patients with asymptomatic Mycobacterium tuberculosis infection, a novel 3-gene transcriptional signature comprising BATF2, GBP5, and SCARF1 achieved a positive predictive value (PPV) of 23% for progression to active tuberculosis within 90 days. In a new UK cohort of 333 HIV-negative tuberculosis contacts with a median follow-up of 346 days, this signature achieved a PPV of 50% (95% confidence interval [CI], 15.7-84.3) and negative predictive value of 99.3% (95% CI, 97.5-99.9). By comparison, peripheral blood interferon gamma release assays in the same cohort achieved a PPV of 5.6% (95% CI, 2.1-11.8). CONCLUSIONS: This blood transcriptional signature provides unprecedented opportunities to target therapy among tuberculosis contacts with greatest risk of incident disease.

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.

Treatment of Latent Tuberculosis Infection: An Updated Network Meta-analysis.

BACKGROUND: Treatment of latent tuberculosis infection (LTBI) is an important component of tuberculosis (TB) control, and this study updates a previous network meta-analysis of the best LTBI treatment options to inform public health action and programmatic management of LTBI. PURPOSE: To evaluate the comparative efficacy and harms of LTBI treatment regimens aimed at preventing active TB among adults and children. DATA SOURCES: PubMed, Embase, and Web of Science from indexing to 8 May 2017; clinical trial registries; and conference abstracts. No language restrictions were applied. STUDY SELECTION: Randomized controlled trials that evaluated human LTBI treatments and recorded at least 1 of 2 prespecified end points (hepatotoxicity and prevention of active TB). DATA EXTRACTION: 2 investigators independently extracted data from eligible studies and assessed study quality according to a standard protocol. DATA SYNTHESIS: The network meta-analysis of 8 new and 53 previously included studies showed that isoniazid regimens of 6 months (odds ratio [OR], 0.65 [95% credible interval {CrI}, 0.50 to 0.83]) or 12 to 72 months (OR, 0.50 [CrI, 0.41 to 0.62]), rifampicin-only regimens (OR, 0.41 [CrI, 0.19 to 0.85]), rifampicin-isoniazid regimens of 3 to 4 months (OR, 0.53 [CrI, 0.36 to 0.78]), rifampicin-isoniazid-pyrazinamide regimens (OR, 0.35 [CrI, 0.19 to 0.61]), and rifampicin-pyrazinamide regimens (OR, 0.53 [CrI, 0.33 to 0.84]) were efficacious compared with placebo. Evidence existed for efficacy of weekly rifapentine-isoniazid regimens compared with no treatment (OR, 0.36 [CrI, 0.18 to 0.73]). No conclusive evidence showed that HIV status altered treatment efficacy. LIMITATION: Evidence was sparse for many comparisons and hepatotoxicity outcomes, and risk of bias was high or unknown for many studies. CONCLUSION: Evidence exists for the efficacy and safety of 6-month isoniazid monotherapy, rifampicin monotherapy, and combination therapies with 3 to 4 months of isoniazid and rifampicin. PRIMARY FUNDING SOURCE: U.K. National Institute for Health Research. (PROSPERO: CRD42016037871).

Latent tuberculosis infection screening and treatment in HIV: insights from evaluation of UK practice.

Latent TB infection (LTBI) screening and treatment in HIV-positive individuals in the UK is advocated by the British HIV Association (BHIVA) and National Institute for Health and Care Excellence (NICE), although each recommends differing strategies. We undertook an evaluation of UK practice, relating the responses to the local HIV/TB disease burden. 162 of 188 (86%) UK geographical areas responded; only 93/162 (57.4%) offer LTBI testing with considerable heterogeneity in practice, and no difference in HIV/TB burden between areas offering testing and those who do not. Only 33/93 (35.5%) and 6/93 (6.5%) reported full compliance with BHIVA and NICE guidance respectively. A uniform national guideline is required.

'"Why me, why now?" Using clinical immunology and epidemiology to explain who gets nontuberculous mycobacterial infection.

BACKGROUND: The prevalence of nontuberculous mycobacterial (NTM) disease is rising. An understanding of known risk factors for disease sheds light on the immunological and physical barriers to infection, and how and why they may be overcome. This review focuses on human NTM infection, supported by experimental and in vitro data of relevance to the practising clinician who seeks to understand why their patient has NTM infection and how to further investigate. DISCUSSION: First, the underlying immune response to NTM disease is examined. Important insights regarding NTM disease susceptibility come from nature's own knockouts, the primary immune deficiency disorders. We summarise the current knowledge surrounding interferon-gamma (IFNγ)-interleukin-12 (IL-12) axis abnormalities, followed by a review of phagocytic defects, T cell lymphopenia and rarer genetic conditions known to predispose to NTM disease. We discuss how these define key immune pathways involved in the host response to NTM. Iatrogenic immunosuppression is also important, and we evaluate the impact of novel biological therapies, as well as bone marrow transplant and chemotherapy for solid organ malignancy, on the epidemiology and presentation of NTM disease, and discuss the host defence dynamics thus revealed. NTM infection and disease in the context of other chronic illnesses including HIV and malnutrition is reviewed. The role of physical barriers to infection is explored. We describe how their compromise through different mechanisms including cystic fibrosis, bronchiectasis and smoking-related lung disease can result in pulmonary NTM colonisation or infection. We also summarise further associations with host factors including body habitus and age. We use the presented data to develop an over-arching model that describes human host defences against NTM infection, where they may fail, and how this framework can be applied to investigation in routine clinical practice.

World TB Day 2016: an interview with leading experts in tuberculosis research.

In this interview, we talk to leading tuberculosis (TB) experts from University College London and the London School of Hygiene and Tropical Medicine about the current challenges in TB research. The video of this interview is available here: https://www.youtube.com/watch?v=75Die7MQBec&feature=youtu.be . The video can also be downloaded via Additional file 1.

Treatment of latent tuberculosis infection: a network meta-analysis.

BACKGROUND: Effective treatment of latent tuberculosis infection (LTBI) is an important component of TB elimination programs. Promising new regimens that may be more effective are being introduced. Because few regimens can be directly compared, network meta-analyses, which allow indirect comparisons to be made, strengthen conclusions. PURPOSE: To determine the most efficacious regimen for preventing active TB with the lowest likelihood of adverse events to inform LTBI treatment policies. DATA SOURCES: PubMed, EMBASE, and Web of Science up to 29 January 2014; clinical trial registries; and conference abstracts. STUDY SELECTION: Randomized, controlled trials that evaluated LTBI treatment in humans and recorded at least 1 of 2 prespecified end points (preventing active TB or hepatotoxicity), without language or date restrictions. DATA EXTRACTION: Data from eligible studies were independently extracted by 2 investigators according to a standard protocol. DATA SYNTHESIS: Of the 1516 articles identified, 53 studies met the inclusion criteria. Data on 15 regimens were available; of 105 possible comparisons, 42 (40%) were compared directly. Compared with placebo, isoniazid for 6 months (odds ratio [OR], 0.64 [95% credible interval {CrI}, 0.48 to 0.83]) or 12 months or longer (OR, 0.52 [CrI, 0.41 to 0.66]), rifampicin for 3 to 4 months (OR, 0.41 [CrI, 0.18 to 0.86]), and rifampicin-isoniazid regimens for 3 to 4 months (OR, 0.52 [CrI, 0.34 to 0.79]) were efficacious within the network. LIMITATIONS: The risk of bias was unclear for many studies across various domains. Evidence was sparse for some comparisons, particularly hepatotoxicity. CONCLUSION: Comparison of different LTBI treatment regimens showed that various therapies containing rifamycins for 3 months or more were efficacious at preventing active TB, potentially more so than isoniazid alone. Regimens containing rifamycins may be effective alternatives to isoniazid monotherapy. PRIMARY FUNDING SOURCE: None.

Impact of prophylactic and 'rescue pack' antibiotics on the airway microbiome in chronic lung disease.

The management of many chronic lung diseases involves multiple antibiotic prescriptions either to treat acute exacerbations or as prophylactic therapy to reduce the frequency of exacerbations and improve patients' quality of life. AIM: To investigate the effects of antibiotics on the homeostasis of bacterial communities in the airways, and how this may contribute to antimicrobial resistance (AMR) among respiratory pathogens and microbiota. METHODS: Within an observational cohort study, sputum was collected from 84 patients with chronic obstructive pulmonary disease and/or bronchiectasis at stable state: 47 were receiving antibiotic prophylaxis therapy. V3-V4 16S-rRNA sequencing on Illumina MiSeq, quantitative PCR for typical respiratory pathogens, bacteriology cultures and antimicrobial susceptibility testing of sputum isolates, resistome analysis on a subset of 17 sputum samples using MinION metagenomics sequencing were performed. FINDING: The phylogenetic α-diversity and the total bacterial density in sputum were significantly lower in patients receiving prophylactic antibiotics (p=0.014 and 0.029, respectively). Antibiotic prophylaxis was associated with significantly lower relative abundance of respiratory pathogens such as Pseudomonas aeruginosa, Moraxella catarrhalis and members of family Enterobacteriaceae in the airway microbiome, but not Haemophilus influenzae and Streptococcus pneumoniae. No major definite directional shifts in the microbiota composition were identified with prophylactic antibiotic use at the cohort level. Surveillance of AMR and resistome analysis revealed a high frequency of resistance to macrolide and tetracycline in the cohort. AMR expressed by pathogenic bacterial isolates was associated with antibiotics prescribed as 'rescue packs' for prompt initiation of self-treatment of exacerbations (Spearman's rho=0.408, p=0.02). CONCLUSIONS: Antibiotic prophylactic therapy suppresses recognised pathogenic bacteria in the sputum of patients with chronic lung disease. The use of antibiotic rescue packs may be driving AMR in this cohort rather than prophylactic antibiotics.

Changes in short-term (in-ICU and in-hospital) mortality following intensive care unit admission in adults living with HIV: 2000-2019.

OBJECTIVE: Limited data suggest intensive care unit (ICU) outcomes have improved in people with HIV (PWH). We describe trends in in-ICU/in-hospital mortality among PWH following admission to ICU in a single UK-based HIV referral centre, from 1 January 2000 to 31 December 2019. METHODS: Modelling of associations between ICU admission and calendar year of admission was done using logistic regression with adjustment for age, sex, Acute Physiology and Chronic Health Evaluation II (APACHE II) score, CD4 + T-cell count and diagnosis of HIV at/within the past 3 months. RESULTS: Among 221 PWH (71% male, median [interquartile range (IQR)] age 45 years [38-53]) admitted to ICU, median [IQR] APACHE II score and CD4 + T-cell count were 19 [14-25] and 122 cells/µl [30-297], respectively; HIV-1 viral load was ≤50 copies/ml in 46%. The most common ICU admission diagnosis was lower respiratory tract infection (30%). In-ICU and in-hospital, mortality were 29 and 38.5%, respectively. The odds of in-ICU mortality decreased over the 20-year period by 11% per year [odds ratio (OR): 0.89 (95% confidence interval (CI): 0.84-0.94)] with in-hospital mortality decreasing by 14% per year [0.86 (0.82-0.91)]. After adjusting for patient demographics and clinical factors, both estimates were attenuated, however, the odds of in-hospital mortality continued to decline over time [in-ICU mortality: adjusted OR: 0.97 (0.90-1.05); in-hospital mortality: 0.90 (0.84-0.97)]. CONCLUSION: Short-term mortality of critically ill PWH admitted to ICU has continued to decline in the ART era. This may result from changing indications for ICU admission, advances in critical care and improvements in HIV-related immune status.

Cross-sectional study evaluating the impact of SARS-CoV-2 variants on Long COVID outcomes in UK hospital survivors.

OBJECTIVES: COVID-19 studies report on hospital admission outcomes across SARS-CoV-2 waves of infection but knowledge of the impact of SARS-CoV-2 variants on the development of Long COVID in hospital survivors is limited. We sought to investigate Long COVID outcomes, aiming to compare outcomes in adult hospitalised survivors with known variants of concern during our first and second UK COVID-19 waves, prior to widespread vaccination. DESIGN: Prospective observational cross-sectional study. SETTING: Secondary care tertiary hospital in the UK. PARTICIPANTS: This study investigated Long COVID in 673 adults with laboratory-positive SARS-CoV-2 infection or clinically suspected COVID-19, 6 weeks after hospital discharge. We compared adults with wave 1 (wildtype variant, admitted from February to April 2020) and wave 2 patients (confirmed Alpha variant on viral sequencing (B.1.1.7), admitted from December 2020 to February 2021). OUTCOME MEASURES: Associations of Long COVID presence (one or more of 14 symptoms) and total number of Long COVID symptoms with SARS-CoV-2 variant were analysed using multiple logistic and Poisson regression, respectively. RESULTS: 322/400 (wave 1) and 248/273 (wave 2) patients completed follow-up. Predictors of increased total number of Long COVID symptoms included: pre-existing lung disease (adjusted count ratio (aCR)=1.26, 95% CI 1.07, 1.48) and more COVID-19 admission symptoms (aCR=1.07, 95% CI 1.02, 1.12). Weaker associations included increased length of inpatient stay (aCR=1.02, 95% CI 1.00, 1.03) and later review after discharge (aCR=1.00, 95% CI 1.00, 1.01). SARS-CoV-2 variant was not associated with Long COVID presence (OR=0.99, 95% CI 0.24, 4.20) or total number of symptoms (aCR=1.09, 95% CI 0.82, 1.44). CONCLUSIONS: Patients with chronic lung disease or greater COVID-19 admission symptoms have higher Long COVID risk. SARS-CoV-2 variant was not predictive of Long COVID though in wave 2 we identified fewer admission symptoms, improved clinical trajectory and outcomes. Addressing modifiable factors such as length of stay and timepoint of clinical review following discharge may enable clinicians to move from Long COVID risk stratification towards improving its outcome.

What's new in respiratory infections and tuberculosis 2008-2010.

Over the past few years there have been an increasing number of research articles published in Thorax on respiratory tract infections (including tuberculosis) affecting children and adults. Although these articles cover a wide variety of areas, several broad themes can be discerned. These include greater interest in viral respiratory infections (partially stimulated by the recent influenza A pandemic), improved characterisation of who is at risk of community-acquired pneumonia and mycobacterial infection, research into better diagnostics and attempts to develop new or improved scoring scales for a range of respiratory infection syndromes. There have also been a limited number of articles on how to manage patients with respiratory infection, including describing the efficacy of prevention by vaccination. Overall, there has been a discernible emphasis on transferring advances in clinical science to actual clinical practice, with several papers using molecular methodologies or measuring levels of cytokines or other potential biomarkers to improve diagnostic accuracy in patients with lung infection. There have also been manuscripts linking specific pathogen genotypes to infection phenotype, an area that is likely to be increasingly important in explaining some of the variations in severity between patients with respiratory infection. However, many questions remain on the optimum strategies for the management and prevention of pneumonia, bronchiectasis and tuberculosis, and there remains a strong need for further clinical research in order to make substantial improvements in the management of patients with lung infection.

Fortuitous vasculitis.

A 43-year-old man with a cardiac device for dilated cardiomyopathy presented with fever, night sweats, and weight loss. Investigations revealed pancytopenia, acute renal failure, abnormal lung function, and raised inflammatory markers. A renal biopsy demonstrated pauci-immune necrotizing crescentic glomerulonephritis. He was diagnosed with pulmonary-renal antineutrophil cytoplasmic antibody-negative systemic small vessel vasculitis. He commenced immunosuppression with prednisolone and cyclophosphamide with recovery from pancytopenia and improvement in renal function 3 months later. Subsequently, a bone marrow culture grew Mycobacterium fortuitum. Isolation on repeat peripheral mycobacterial blood cultures prompted treatment with ciprofloxacin and clarithromycin. Four months later, he presented with neutropenic sepsis, influenza A/H1N1, and Aspergillus flavus pneumonia. Despite treatment he deteriorated. A transthoracic echocardiogram revealed a vegetation on the right ventricular pacing wire. The device was removed. The vegetation revealed acid and alcohol fast bacilli on Ziehl-Neelsen staining and grew M. fortuitum on culture, sensitive to ciprofloxacin and clarithromycin. Despite device removal and antimicrobial therapy, the patient succumbed to treatment-related complications. The association between glomerulonephritis and endocarditis is well known; however, this is the first case to our knowledge describing pauci-immune necrotizing crescentic glomerulonephritis in the context of M. fortuitum endocarditis. Clinicians should maintain a high index of suspicion for endocarditis in patients with a cardiac device who present with fever and pauci-immune necrotizing crescentic glomerulonephritis. Patients should be investigated with mycobacterial blood cultures, at least three sets of standard blood cultures and transthoracic and transesophageal echocardiography. Clinicians should beware the perils of immunosuppression in the face of an occult sepsis.

Case studies to illustrate good practice in the management of non-tuberculous mycobacterial pulmonary disease.

Pulmonary disease caused by non-tuberculous mycobacteria (NTM-PD) can be a complex condition for health care providers to manage, and delayed diagnosis and treatment failure are common. Here we present three case studies that illustrate key challenges in the diagnosis and treatment of NTM-PD, and provide guidance on these issues. In addition, we make recommendations on how the overall management of NTM-PD may be improved, through strategies such as physician education to recognise NTM-PD, and the development of multidisciplinary teams and patient-support groups.

Reducing the risk of tuberculosis transmission for HCWs in high incidence settings.

Globally, tuberculosis (TB) is a leading cause of death from a single infectious agent. Healthcare workers (HCWs) are at increased risk of hospital-acquired TB infection due to persistent exposure to Mycobacterium tuberculosis (Mtb) in healthcare settings. The World Health Organization (WHO) has developed an international system of infection prevention and control (IPC) interventions to interrupt the cycle of nosocomial TB transmission. The guidelines on TB IPC have proposed a comprehensive hierarchy of three core practices, comprising: administrative controls, environmental controls, and personal respiratory protection. However, the implementation of most recommendations goes beyond minimal physical and organisational requirements and thus cannot be appropriately introduced in resource-constrained settings and areas of high TB incidence. In many low- and middle-income countries (LMICs) the lack of knowledge, expertise and practice on TB IPC is a major barrier to the implementation of essential interventions. HCWs often underestimate the risk of airborne Mtb dissemination during tidal breathing. The lack of required expertise and funding to design, install and maintain the environmental control systems can lead to inadequate dilution of infectious particles in the air, and in turn, increase the risk of TB dissemination. Insufficient supply of particulate respirators and lack of direction on the re-use of respiratory protection is associated with unsafe working practices and increased risk of TB transmission between patients and HCWs. Delayed diagnosis and initiation of treatment are commonly influenced by the effectiveness of healthcare systems to identify TB patients, and the availability of rapid molecular diagnostic tools. Failure to recognise resistance to first-line drugs contributes to the emergence of drug-resistant Mtb strains, including multidrug-resistant and extensively drug-resistant Mtb. Future guideline development must consider the social, economic, cultural and climatic conditions to ensure that recommended control measures can be implemented in not only high-income countries, but more importantly low-income, high TB burden settings. Urgent action and more ambitious investments are needed at both regional and national levels to get back on track to reach the global TB targets, especially in the context of the COVID-19 pandemic.

The Blood Neutrophil Count After 1 Month of Treatment Predicts the Radiologic Severity of Lung Disease at Treatment End.

BACKGROUND: Lung disease after tuberculous confers significant morbidity. However, the determinants of persistent lung damage in TB are not well established. We investigated associations between TB-associated radiologic changes and sociodemographic factors, surrogates of bacillary burden, and blood inflammatory markers at initiation of therapy and after 1 month. RESEARCH QUESTION: What are the predictors of radiologic severity at the end of TB treatment for TB? STUDY DESIGN AND METHODS: We collected data from patients treated for drug-sensitive pulmonary TB at our center over a 5.5-year period. We recorded age, sex, ethnicity, smoking status, symptom duration, sputum smear grade, time to culture positivity, and blood results (C-reactive protein and neutrophil count) at baseline and after 1 month of treatment. Chest radiographs obtained at baseline, 2 months, and end of treatment were assessed independently by two radiologists and scored using a validated system. Relationships between predictor variables and radiologic outcomes were assessed using linear or binary logistic regression. RESULTS: We assessed 154 individuals with a mean age of 37 years, 63% of whom were men. In a multivariate analysis, baseline radiologic severity correlated with sputum smear grade (P = 0.003) and neutrophil count (P < 0.001). At end of treatment, only the 1-month neutrophil count was associated significantly with overall radiologic severity in the multivariate analysis (r = 0.34; P = 0.003) and remained significant after controlling for baseline radiologic scores. The 1-month neutrophil count also was the only independent correlate of volume loss and pleural thickening at the end of treatment and was significantly higher in patients with persistent cavitation or effusion vs those without. INTERPRETATION: Persistent neutrophilic inflammation after 1 month of TB therapy is associated with poor radiologic outcome, suggesting a target for interventions to minimize lung disease after tuberculous.