PT - JOURNAL ARTICLE AU - L Jayaram AU - K Parameswaran AU - MR Sears AU - FE Hargreave TI - Induced sputum cell counts: their usefulness in clinical practice AID - 10.1034/j.1399-3003.2000.16a27.x DP - 2000 Jul 01 TA - European Respiratory Journal PG - 150--158 VI - 16 IP - 1 4099 - http://erj.ersjournals.com/content/16/1/150.short 4100 - http://erj.ersjournals.com/content/16/1/150.full SO - Eur Respir J2000 Jul 01; 16 AB - Airway inflammation is fundamental to the aetiology and persistence of asthma and other airway conditions. The presence and type of airway inflammation can be difficult to detect clinically, delaying the introduction of appropriate treatment. Induced sputum cell counts are a relatively noninvasive, safe and reliable method of identifying airway inflammation. They can accurately discriminate eosinophilic airway inflammation from noneosinophilic airway inflammation, and help guide therapy. Eosinophilic airway inflammation is steroid responsive whilst noneosinophilic (usually neutrophilic) inflammation generally is not. Macrophages containing haemosiderin can be useful in detecting left ventricular dysfunction and macrophages containing lipid are suggestive of oropharyngeal reflux with microaspiration, both of which can complicate or confuse assessment of airway disease. To date, studies using induced sputum are primarily observational. Management studies based on examination of induced sputum are now needed to validate the clinical utility of this test.