Level of eosinophil cationic protein in sputum of chemical warfare victims

ABSTRACT

Considering fair response to inhaled corticosteroids and reports of severe air way hyper responsiveness in chemical warfare victims [CWV], a role for eosinophilic inflammation [i.e. asthma] was postulated. The objective of this study was to determine the presence of eosinophilic inflammation in CWV by evaluation of Sputum cellularity and eosinophil cationic protein [ECP]. Forty CWV and 15 control subjects entered this cross sectional study. Demographic data, dyspnea severity scale, spirometry results and 6 min walk test were determined. Sputum was collected with inducing by nebulizing hypertonic saline and analyzed for total inflammatory cell count, the cellular differential count and ECP level. Control group was normal volunteers with PC[20] more than 8 mg/ml. Mean +/- SD of eosinophil percentage [11.7 +/- 11.1%] and ECP level in sputum of CWV [46.1 +/- 19.5 ng/ml] were significantly more than control group. Regression analysis showed significant correlation between ECP level and percentage of eosinophils in sputum [r= +0.43, P< 0.01]. ECP level of CWV subjects with obstructive pattern did not show any significant difference from CWV with normal spirometry. ECP level in CWV subjects who revealed more than 12% improvement in forced expiratory volume in one second [FEV1] was significantly higher than CWV who had improvement less than 12% [P= 0.01]. BO and asthma as final clinical diagnosis of CWV did not show any significant difference of sputum ECP. Bronchial inflammation in different types of pulmonary complication of CWV is eosinophil dependent. ECP level of sputum in CWV could guide physician to select CWV who would respond to corticosteroids