Global strategy for asthma management and prevention

This document is an international evidence-based guideline on the diagnosis and management of idiopathic pulmonary fibrosis, and is a collaborative effort of the American Thoracic Society, the European Respiratory Society, the Japanese Respiratory Society, and the Latin American Thoracic Association. It represents the current state of knowledge regarding idiopathic pulmonary fibrosis (IPF), and contains sections on definition and epidemiology, risk factors, diagnosis, natural history, staging and prognosis, treatment, and monitoring disease course. For the diagnosis and treatment sections, pragmatic GRADE evidence-based methodology was applied in a question-based format. For each diagnosis and treatment question, the committee graded the quality of the evidence available (high, moderate, low, or very low), and made a recommendation (yes or no, strong or weak). Recommendations were based on majority vote. It is emphasized that clinicians must spend adequate time with patients to discuss patients' values and preferences and decide on the appropriate course of action.

An Official ATS/ERS/JRS/ALAT Statement: Idiopathic Pulmonary Fibrosis: Evidence-Based Guidelines for Diagnosis and Management

SERIES “ATS/ERS TASK FORCE: STANDARDISATION OF LUNG FUNCTION TESTING” 

Edited by V. Brusasco, R. Crapo and G. Viegi 

Number 5 in this Series 







This section is written to provide guidance in interpreting pulmonary function tests (PFTs) to medical directors of hospital-based laboratories that perform PFTs, and physicians who are responsible for interpreting the results of PFTs most commonly ordered for clinical purposes. Specifically, this section addresses the interpretation of spirometry, bronchodilator response, carbon monoxide diffusing capacity ( D L,CO) and lung volumes.

The sources of variation in lung function testing and technical aspects of spirometry, lung volume measurements and D L,CO measurement have been considered in other documents published in this series of Task Force reports 1–4 and in the American Thoracic Society (ATS) interpretative strategies document 5.

An interpretation begins with a review and comment on test quality. Tests that are less than optimal may still contain useful information, but interpreters should identify the problems and the direction and magnitude of the potential errors. Omitting the quality review and relying only on numerical results for clinical decision making is a common mistake, which is more easily made by those who are dependent upon computer interpretations.

Once quality has been assured, the next steps involve a series of comparisons 6 that include comparisons of test results with reference values based on healthy subjects 5, comparisons with known disease or abnormal physiological patterns ( i.e. obstruction and restriction), and comparisons with self, a rather formal term for evaluating change in an individual patient. A final step in the lung function report is to answer the clinical question that prompted the test.

Poor choices made during these preparatory steps increase the risk of misclassification, i.e. a falsely negative or falsely positive interpretation for a lung function abnormality or a change …

https://erj.ersjournals.com/content/erj/26/5/948.full.pdf

Interpretative strategies for lung function tests

Lung volumes are subdivided into static and dynamic lung volumes. Static lung volumes are measured by methods which are based on the completeness of respiratory manoeuvres, so that the velocity of the manoeuvres should be adjusted accordingly. The measurements taken during fast breathing movements are described as dynamic lung volumes and as forced inspiratory and expiratory flows.

### 1.1 Static lung volumes and capacities

The volume of gas in the lung and intrathoracic airways is determined by the properties of lung parenchyma and surrounding organs and tissues, surface tension, the force exerted by respiratory muscles, by lung reflexes and by the properties of airways. The gas volumes of thorax and lung are the same except in the case of a pneumothorax. If two or more subdivisions of the total lung capacity are taken together, the sum of the constituent volumes is described as a lung capacity. Lung volumes and capacities are described in more detail in § 2.

#### 1.1.1 Determinants

Factors which determine the size of the normal lung include stature, age, sex, body mass, posture, habitus, ethnic group, reflex factors and daily activity pattern. The level of maximal inspiration (total lung capacity, TLC) is influenced by the force developed by the inspiratory muscles (disorders include e.g. muscular dystrophy), the elastic recoil of the lung (disorders include e.g. pulmonary fibrosis and emphysema) and the elastic properties of the thorax and adjacent structures (disorders include e.g. ankylosis of joints). The level of maximal expiration (residual volume, RV) is determined by the force exerted by respiratory muscles (disorders include e.g. muscle paralysis), obstruction, occlusion and compression of small airways (disorders include e.g. emphysema) and by the mechanical properties of lung and thorax (disorders include diffuse fibrosis, kyphoscoliosis).

Assessing the total lung capacity is indispensable in establishing a restrictive ventilatory defect or in diagnosing abnormal lung distensibility, as may occur in patients …

Lung volumes and forced ventilatory flows

Diagnostic Criteria of Nontuberculous Mycobacterial Lung Disease Key Laboratory Features of NTM Health Careand Hygiene-associated Disease Prevention Prophylaxis and Treatment of NTM Disease Introduction Methods Taxonomy Epidemiology Pathogenesis Host Defense and Immune Defects Pulmonary Disease Body Morphotype Tumor Necrosis Factor Inhibition Laboratory Procedures Collection, Digestion, Decontamination, and Staining of Specimens Respiratory Specimens Body Fluids, Abscesses, and Tissues Blood Specimen Processing Smear Microscopy Culture Techniques Incubation of NTM Cultures NTM Identification Antimicrobial Susceptibility Testing for NTM Molecular Typing Methods of NTM Clinical Presentations and Diagnostic Criteria Pulmonary Disease Cystic Fibrosis Hypersensitivity-like Disease Transplant Recipients Disseminated Disease Lymphatic Disease Skin, Soft Tissue, and Bone Disease

/pdf/an-official-ats-idsa-statement-diagnosis-treatment-and-1jy41yfwpp.pdf

An official ATS/IDSA statement: diagnosis, treatment, and prevention of nontuberculous mycobacterial diseases.

Online Case 83

Online Case 82

Online Case 79

Wegener's granulomatosis is a multisystemicdisease, histologically characterized by granulomatousinflammation and vasculitis that typically affects therespiratory tract and the kidneys. Its victims are usuallymiddle aged, and there is no gender bias. The mostcommon clinical manifestations include sinusitis,rhinorrhea, nasal/oral ulcers, polyarthralgia, fever,cough and hemoptysis. Antineutrophil cytoplasmicantibody (c-ANCA) is related to the spread of thedisease and is found in approximately 90% of patientspresenting Wegener's granulomatosis accompaniedby respiratory and renal involvement. Despite beingwidely used as a means of confirming the diagnosis,c-ANCA is not specific to Wegener's granulomatosis.The lungs may also be involved at any stage ofthe disease. Computed tomography is superior tochest X-ray in identifying pulmonary abnormalities,as well as in determining the pattern and extent ofthe same.Radiological manifestations typically includemultiple nodules and masses of varying sizes, withregular or irregular borders and in any region of thelung. Cavitation is seen in approximately half of allcases. With treatment, the pulmonary abnormalitiesmay be resolved completely or may leave some areasof scarring.Cavitary colonization by Aspergillus and theformation of aspergillomas are extremely rare inpatients with Wegener's granulomatosis. Aspergilloma(fungus ball) is a conglomeration of hyphae withmucous and cellular debris found in pre-existingcavities or in dilated bronchi. In most cases,aspergillomas are found in patients with a history oftuberculosis. Other predisposing conditions includesarcoidosis, chronic fungal cavitation and ankylosingspondylitis.

/pdf/diagnosis-of-the-case-presented-in-the-previous-edition-3b782nt2gs.pdf

Nestor L. Müller

Papers

Online Case 83

Online Case 82

Online Case 79

Diagnosis of the case presented in the previous edition

Online Case 71