Messung der Atemwegsentzündung in der pneumologischen Praxis - Anwendung und Interpretation

Abstract

Airway inflammation plays a major role in the pathology of both asthma and COPD and is the target of corticosteroid treatment. In daily routine practise, however, airway inflammation is still not often considered by pneumologists to support the diagnostic process or to aid in disease management, despite studies showing that patients could benefit. Eosinophilic airway inflammation is of special interest, as it is not restricted to allergen-induced airway diseases, and because it generally responds well to anti-inflammatory treatment with corticosteroids. Therefore, the early detection of this kind of underlying inflammatory process can have a positive impact on finding a diagnosis as well as for disease management. The non-invasive detection of eosinophilic airway inflammation using induced sputum is too time consuming and therefore too expensive in outpatient settings. As sputum eosinophils correlate with the concentration of exhaled nitric oxide (FeNO), its measurement could serve as a more economic alternative, especially as new small handheld analysers are available now, that allow the rapid FeNO analysis, even in children. This review will cover some basics and technical aspects of FeNO measurements, which should be known to correctly interprete results in clinical practise. In the second part, the clinical value and the limits of FeNO measurements, as well as the potential interpretation of results are discussed based on recently published literature.

Hurdles on the way to the diagnosis of asthma and successful therapy

“…When making the diagnosis of asthma the disease must of course be distinguished from several other distinct or potentially co-existing diseases in addition to COPD and ACO referred to above. This differential diagnosis includes rarer diseases such as cystic fibrosis, interstitial lung disease, vocal cord dysfunction (VCD), dysfunctional breathing, ciliary dysfunction, upper airway cough syndrome, gastro-oesophageal reflux (GERD) with or without obesity, foreign body aspiration, pulmonary embolism, lung cancer, respiratory tract infections such as pertussis and tuberculosis and extra-pulmonary diseases such as cardiac failure [5][6][7][8][9].…”

Aktuelle internistische Literatur referiert und kommentiert

“…andere Erkrankungen, bei denen die eosinophile Entzündung dominiert (vor allem Allergien auch ohne Asthma), den akuten Virusinfekt oder das Rauchen (= falsch niedrige FeNO-Werte). Ferner sind folgende Einflussfaktoren des FeNO bekannt: Atemfluss, tageszeitliche Schwankungen, nitratreiche Kost und Lebensalter [10]. Zudem gibt es Patienten, die trotz einer nach Symptomen und Lungenfunktion erfolgreichen ICS-Behandlung unverändert hohe FeNO-Werte aufweisen.…”

Study on the Relationship Between Bronchoalveolar Lavage Fluid Cell Count, Th1/Th2 Cytokines and Pulmonary Function in Patients with Cough Variant Asthma

“…16 The measurements are of great significance for disease diagnosis, but the clinical instruments applied to detect FeNO are expensive and have not been widely used in most grass-roots hospitals. 17 A positive bronchial provocation test is the gold standard for the diagnosis of CVA. 18 The methacholine bronchial provocation test is essential in the diagnosis of chronic cough related to bronchial hyperresponsiveness, 19 and FeNO is one of the non-invasive indicators for observing airway inflammation.…”