Granulocyte activation markers in induced sputum: comparison between chronic obstructive pulmonary disease, asthma, and normal subjects.

Department of Thoracic Medicine, National Heart and Lung Institute, London, United Kingdom.
American Journal of Respiratory and Critical Care Medicine (Impact Factor: 11.99). 03/1997; 155(2):449-53. DOI: 10.1164/ajrccm.155.2.9032177
Source: PubMed

ABSTRACT Airway inflammation is present in asthma and is thought to play a significant part in the development of airflow obstruction. In chronic obstructive pulmonary disease (COPD), neutrophilic inflammation is present in the airway lumen, whereas the submucosa displays a lymphocytic infiltrate. Less is known about the nature and mechanisms of inflammation in COPD than in asthma. Induced sputum allows noninvasive sampling of respiratory tract secretions from patients and control subjects, allowing characterization of cells and measurement of soluble markers. We exploited this technique in order to compare the presence and quantify specific markers of eosinophil and neutrophil activation in subjects with asthma or COPD, and control subjects. Differential cell counts showed significantly higher neutrophil percentages in the patients with COPD compared with other groups, while patients with asthma had higher numbers of eosinophils. The neutrophil markers myeloperoxidase (MPO), from primary granules in neutrophils, and human neutrophil lipocalin (HNL), released from secondary granules, were elevated in patients with asthma and COPD compared with control subjects but markedly more so in COPD. The difference between COPD and asthma was more marked for HNL than for MPO suggesting that HNL may be a better marker for discriminating between these conditions. Concentrations of the eosinophil granule protein, eosinophil cationic protein (ECP), and the eosinophil granule-derived enzyme, eosinophil peroxidase (EPO) were raised in the patients with asthma and those with COPD.

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    ABSTRACT: Background The protein neutrophil gelatinase-associated lipocalin (NGAL) is a mediator synthesized and released by neutrophils. Its physiological function is as yet unclear. Levels in blood increase in several inflammatory diseases. High serum values indicate poor prognosis for several diseases. Pleural effusion may appear as the result of various pathologies. The most common cause is heart failure (HF). Other common causes include parapneumonic (PPE) and malignant (MPE) pleural effusions, and pulmonary embolism. Tubercular effusion (TE) is commonly encountered in Turkey and similar developing countries. The purpose of this study was to investigate the effectiveness of NGAL, a current inflammation marker, in discriminating between different etiological diseases that cause pleural effusion. Methods The study was performed at the Recep Tayyip Erdoğan University Faculty of Medicine Chest Diseases Clinic. One hundred patients were included in the study, 25 with parapneumonic effusion, 25 with heart failure-related effusion, 25 with tubercular effusion and 25 with cancer-related effusion. NGAL was measured in patients’ serum and pleural fluids. Results Serum NGAL levels in PPE (171 ± 56 ng/ml) were significantly higher (p < 0.001) than those in HF (86 ± 31 ng/ml), CA (103 ± 42 ng/ml) and TE (63 ± 19 ng/ml). Pleural NGAL levels were also significantly higher in PPE compared to HF, MPE and TE (p < 0.001). Serum NGAL levels exhibited a positive correlation with white blood cell (WBC), neutrophil, C-reactive protein (CRP), sedimentation, serum LDH, creatinine, pleural leukocyte and pleural neutrophil numbers. The most significant correlation was between NGAL level and WBC (p < 0.001, r = 0.579). Both serum and pleural NGAL levels are highly effective in differentiating patients with PPE from those without PPE (AUC: 0.910 and 0.790, respectively). Conclusions NGAL can be used in the diagnosis of diseases with an acute inflammatory course. Serum and pleural NGAL levels can differentiate PPE from other diseases causing pleural fluid with high sensitivity and specificity.
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    Respirology 07/2013; 18(5). DOI:10.1111/resp.12079 · 3.50 Impact Factor