Background: The American Thoracic Society, U.S. Centers for Disease Control and Prevention, European Respiratory Society, and Infectious Diseases Society of America jointly sponsored this new practice guideline on the treatment of drug-resistant tuberculosis (DR-TB). The document includes recommendations on the treatment of multidrug-resistant TB (MDR-TB) as well as isoniazid-resistant but rifampin-susceptible TB. Methods: Published systematic reviews, meta-analyses, and a new individual patient data meta-analysis from 12,030 patients, in 50 studies, across 25 countries with confirmed pulmonary rifampin-resistant TB were used for this guideline. Meta-analytic approaches included propensity score matching to reduce confounding. Each recommendation was discussed by an expert committee, screened for conflicts of interest, according to the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. Results: Twenty-one Population, Intervention, Comparator, and Outcomes questions were addressed, generating 25 GRADE-based recommendations. Certainty in the evidence was judged to be very low, because the data came from observational studies with significant loss to follow-up and imbalance in background regimens between comparator groups. Good practices in the management of MDR-TB are described. On the basis of the evidence review, a clinical strategy tool for building a treatment regimen for MDR-TB is also provided. Conclusions: New recommendations are made for the choice and number of drugs in a regimen, the duration of intensive and continuation phases, and the role of injectable drugs for MDR-TB. On the basis of these recommendations, an effective all-oral regimen for MDR-TB can be assembled. Recommendations are also provided on the role of surgery in treatment of MDR-TB and for treatment of contacts exposed to MDR-TB and treatment of isoniazid-resistant TB.

Background: There is growing interest in identifying early stages of interstitial lung disease (ILD) to improve patient outcomes. This document reviews updated evidence on interstitial lung abnormalities (ILAs); provides suggestions for screening, evaluation, and management; proposes criteria for distinguishing ILAs from ILD; and identifies research priorities. Methods: A committee of clinical and methodology experts met by video conference to define ILAs and ILD by consensus and voted on 11 prespecified questions after reviewing synthesized evidence from a systematic literature search. Agreement of ≥70% was required to approve each suggestion. Results: ILA is defined as nondependent bilateral parenchymal abnormalities on computed tomography, including ground-glass opacities or reticulations, lung distortion, traction bronchiectasis, and/or honeycombing involving ≥5% of a lung zone. The updated definition removes the prior exclusion of high-risk populations. ILD is distinguished from ILAs by symptoms (dyspnea/cough) attributable to an interstitial process, abnormal or declining lung function, fibrotic (honeycombing and/or reticulation with traction bronchiectasis involving ≥5% of total lung volume) or progressive imaging abnormalities, and/or specific fibrotic ILD patterns on imaging or pathology. Suggestions include ILA/ILD assessment on imaging acquired for lung cancer screening, screening adults with connective tissue disease and first-degree relatives of patients with familial pulmonary fibrosis, assessing baseline symptoms and pulmonary function among those with ILAs, and monitoring ILAs with chest computed tomography every 2–3 years. Conclusions: This document presents a comprehensive literature review of ILAs with updates to the Fleischner Society ILA definition, establishes a working ILD definition, and provides evidence-based suggestions for ILA evaluation and management.

Rationale: In 2018, a systematic review evaluating transbronchial lung cryobiopsy (TBLC) in patients with interstitial lung disease (ILD) was performed to inform American Thoracic Society, European Respiratory Society, Japanese Respiratory Society, and Asociación Latinoamericana del Tórax clinical practice guidelines on the diagnosis of idiopathic pulmonary fibrosis. Objectives: To perform a new systematic review to inform updated guidelines. Methods: Medline, Excerpta Medica Database, and the Cochrane Central Register of Controlled Trials (CCTR) were searched through June 2020. Studies that enrolled patients with ILD and reported the diagnostic yield or complication rates of TBLC were selected for inclusion. Data was extracted and then pooled across studies via meta-analysis. The quality of the evidence was appraised using the grading of recommendations, assessment, development, and evaluation approach. Results: Histopathologic diagnostic yield (number of procedures that yielded a histopathologic diagnosis divided by the total number of procedures performed) of TBLC was 80% (95% confidence interval [CI], 76–83%) in patients with ILD. TBLC was complicated by bleeding and pneumothorax in 30% (95% CI, 20–41%) and 8% (95% CI, 6–11%) of patients, respectively. Procedure-related mortality, severe bleeding, prolonged air leak, acute exacerbation, respiratory failure, and respiratory infection were rare. The quality of the evidence was very low owing to the uncontrolled study designs, lack of consecutive enrollment, and inconsistent results. Conclusions: Very low-quality evidence indicated that TBLC has a diagnostic yield of approximately 80% in patients with ILD, with manageable complications.

Background: The American Thoracic Society, European Respiratory Society, Japanese Respiratory Society, and Asociación Latinoamericana del Tórax convened to update clinical practice guidelines for interstitial lung disease (ILD). Objective: To conduct a systematic review to evaluate existing ILD literature to determine whether patients with progressive pulmonary fibrosis (PPF) should be treated with the antifibrotic nintedanib. Data Sources: A literature search was conducted across MEDLINE, EMBASE, and Cochrane databases through December 2020 for studies using nintedanib to treat patients with PPF. Data Extraction: Mortality, disease progression, and adverse event data were extracted, and meta-analyses performed when possible. The Grading of Recommendations, Assessment, Development and Evaluation (GRADE) Working Group approach was used to assess the quality of evidence. Synthesis: Two relevant studies were selected. The annual decline in forced vital capacity was less in the nintedanib arm in the overall study population (mean difference [MD], 107 ml/yr; 95% confidence interval [CI], 65.4 to 148.5 ml/yr) and in the subgroups with usual interstitial pneumonia (UIP) pattern of pulmonary fibrosis (MD, 128.2 ml/yr; 95% CI, 70.8 to 185.6 ml/yr), non-UIP patterns of pulmonary fibrosis (MD, 75.3 ml/yr; 95% CI, 15.5 to 135.0 ml/yr), fibrotic connective tissue disease-related ILD (MD, 106.2 ml/yr; 95% CI, 10.6 to 201.9 ml/yr), fibrotic idiopathic nonspecific interstitial pneumonia (MD, 141.7 ml/yr; 95% CI, 46.0 to 237.4 ml/yr), and fibrotic occupational ILD (MD, 252.8 ml/yr; 95% CI, 79.2 to 426.5 ml/yr), but not fibrotic hypersensitivity pneumonitis (MD, 72.9 ml/yr; 95% CI, −8.9 to 154.7 ml/yr), fibrotic sarcoidosis (MD, −20.5 ml/yr; 95% CI, −337.1 to 296.1 ml/yr), or unclassified fibrotic ILD (MD, 68.5 ml/yr; 95% CI, −31.3 to 168.4 ml/yr) when compared with placebo. Gastrointestinal side effects were common. Quality of evidence for the outcomes ranged from very low to moderate GRADE. Conclusions: Nintedanib use in patients with PPF is associated with a statistically significant decrease in disease progression but increase in gastrointestinal side effects regardless of the radiographic pattern of pulmonary fibrosis. However, limitations in the available evidence lead to low certainty in these effect estimates and make definitive conclusions about the differential effects by subtype of ILD difficult to determine. Primary Source of Funding: Funded by the American Thoracic Society, European Respiratory Society, Japanese Respiratory Society, and Asociación Latinoamericana del Tórax.

Background: The American Thoracic Society, European Respiratory Society, Japanese Respiratory Society, and Asociación Latinoamericana del Tórax convened to update clinical practice guidelines for interstitial lung disease (ILD). Objective: To conduct a systematic review to evaluate existing ILD literature to determine whether patients with progressive pulmonary fibrosis (PPF) should be treated with the antifibrotic pirfenidone. Data Sources: A literature search was conducted across MEDLINE, EMBASE, and Cochrane databases through December 2020 for studies using pirfenidone to treat patients with PPF. Data Extraction: Mortality, disease progression, lung function, and adverse event data were extracted. Meta-analyses were performed when possible. The Grading of Recommendations, Assessment, Development and Evaluation Working Group approach was used to assess the quality of evidence. Synthesis: Two studies met inclusion criteria. Meta-analyses revealed that changes in forced vital capacity (FVC) percent predicted (mean difference [MD], 2.3%; 95% confidence interval [CI], 0.5-4.1%), the FVC in milliliters (MD, 100.0 ml; 95% CI, 98.1-101.9 ml), and the 6-minute-walk distance in meters (MD, 25.2 m; 95% CI, 8.3-42.1 m) all favored pirfenidone over placebo. The changes in the diffusing capacity of the lung for carbon monoxide (DLCO) in millimoles per kilopascal per minute (MD, 0.40 mmol/kPa/min; 95%, CI 0.10-0.70 mmol/kPa/min) and risk of DLCO declining more than 15% (relative risk [RR], 0.27; 95% CI, 0.08-0.95) also favored pirfenidone. The risks of gastrointestinal discomfort (RR, 1.83; 95% CI, 1.29-2.60) and photosensitivity (RR, 4.88; 95% CI, 1.09-21.83) were higher with pirfenidone. The quality of the evidence was low or very low according to the Grading of Recommendations, Assessment, Development and Evaluation criteria, depending on the outcome. Conclusions: Pirfenidone use in patients with PPF is associated with a statistically significant decrease in disease progression and with protection of lung function. However, there is very low certainty in the estimated effects because of limitations in the available evidence. Primary Source of Funding: Funded by the American Thoracic Society, European Respiratory Society, Japanese Respiratory Society, and Asociación Latinoamericana del Tórax.

Rationale: Idiopathic pulmonary fibrosis (IPF) is a fibrosing interstitial pneumonia with impaired survival. Previous guidelines recommend antacid medication to improve respiratory outcomes in patients with IPF. Objectives: This systematic review was undertaken during the development of an American Thoracic Society, European Respiratory Society, Japanese Respiratory Society, and Asociación Latinoamericana del Tórax guideline. The clinical question was, “Should patients with IPF who have documented abnormal gastroesophageal reflux (GER) with or without symptoms of GER disease 1) be treated with antacid medication or 2) undergo antireflux surgery to improve respiratory outcomes?” Methods: Medline, Embase, the Cochrane Central Register of Controlled Trials, and the gray literature were searched through June 30, 2020. Studies that enrolled patients with IPF and 1) compared antacid medication to placebo or no medication or 2) compared antireflux surgery to no surgery were selected. Meta-analyses were performed when possible. Outcomes included disease progression, mortality, exacerbations, hospitalizations, lung function, respiratory symptoms, GER severity, and adverse effects/complications. Results: For antacid medication, when two studies were aggregated, there was no statistically significant effect on disease progression, defined as a 10% or more decline in FVC, more than 50-m decline in 6-minute walking distance, or death (risk ratio [RR], 0.88; 95% confidence interval [CI], 0.76–1.03). A separate study that could not be included in the meta-analysis found no statistically significant effect on disease progression when defined as a 5% or more decline in FVC or death (RR, 1.10; 95% CI, 1.00–1.21) and an increase in disease progression when defined as a 10% or more decline in FVC or death (RR, 1.28; 95% CI, 1.08–1.51). For antireflux surgery, there was also no statistically significant effect on disease progression (RR, 0.29; 95% CI, 0.06–1.26). Neither antacid medications nor antireflux surgery was associated with improvements in the other outcomes. Conclusions: There is insufficient evidence to conclude that antacid medication or antireflux surgery improves respiratory outcomes in patients with IPF, most of whom had not had abnormal GER confirmed. Well-designed and adequately powered prospective studies with objective evaluation for GER are critical to elucidate the role of antacid medication and antireflux surgery for respiratory outcomes in patients with IPF.