摘要
Objective To evaluate the clinical application of the detection of stable end products of NO, nitrite and nitrate (NO - 2/NO - 3) in sputum in patients with asthma. Methods Forty five patients with asthma at remission (GroupⅠ, n=15) or exacerbation state with mild attack (GroupⅡ, n=15) and moderate to severe attack (Group Ⅲ, n=15), also 20 normal control subjects (Group Ⅳ) were included in this study. Most subjects underwent sputum induction by nebulizing 3.5% saline by an ultrasonic nebulizer for 20 minutes. Sputum of 7 patients in Group Ⅲ was sampled through the endotrocheal tube or the spontaneous cough. Sputum was selected from saliva and reduced using 1% dithiothreitol (DTT). The criteria for the quality control of sputum is that the proportion of squamous cell was less than 20% or less than 3 per high power field in slide, with the viability above 50%. The biochemical analysis was performed on supernatants obtained after centrifugation. NO - 2/NO - 3 in sputum was tested by Griess reaction, while the eosinophil cationic protein (ECP) in sputum was determined by florescent enzyme immunoassay. Serum NO - 2/NO - 3 and pulmonary function, including the forced expiratory volume in one second (FEV1.0) and percent of the predicated FEV1.0 (FEV1.0%) were also tested synchronously. Patients in Group Ⅲ received systemic steroid via an oral or intravenous route and after 7-10 days of treatment, all parameters were repeated and compared with that before the treatment. Results The median concentrations of sputum NO - 2/NO - 3 in GroupsⅠ, Ⅱ, and Ⅲ were 84.85, 130.71, and 135.81 μmol/L, respectively, all significantly higher than that in controls (63.19 μmol/L) . In addition, those of Groups Ⅱ and Ⅲ were significantly higher than that of Group Ⅰ. No significant difference was found between that of patients in Groups Ⅱ and Ⅲ. Moreover, the levels of NO derivatives in sputum were closely correlated with the degree of airflow obstruction and sputum ECP levels in patients with asthma at remission ( r = -0.587, P <0.05; r =0.535, P <0.01 respectively) and exacerbation ( r =-0.485, P <0.05; r =0.563, P <0.05 respectively). There was no significant correlation between serum and sputum NO - 2/NO - 3, also no significant correlation between that in serum and the degree of airflow obstruction. A significant decrease of median concentration of sputum NO - 2/NO - 3 was observed after the systematic steroid treatment in asthmatic patients with moderate to severe attack (135.81 vs 92.49 μmol/L) with the improvement of pulmonary function, but it was still significantly higher than that of the controls. Conclusion The NO - 2/NO - 3 in sputum may be a useful marker for monitoring the state of airway inflammation and assessing the therapeutic efficacy.
Objective To evaluate the clinical application of the detection of stable end products of NO, nitrite and nitrate (NO - 2/NO - 3) in sputum in patients with asthma. Methods Forty five patients with asthma at remission (GroupⅠ, n=15) or exacerbation state with mild attack (GroupⅡ, n=15) and moderate to severe attack (Group Ⅲ, n=15), also 20 normal control subjects (Group Ⅳ) were included in this study. Most subjects underwent sputum induction by nebulizing 3.5% saline by an ultrasonic nebulizer for 20 minutes. Sputum of 7 patients in Group Ⅲ was sampled through the endotrocheal tube or the spontaneous cough. Sputum was selected from saliva and reduced using 1% dithiothreitol (DTT). The criteria for the quality control of sputum is that the proportion of squamous cell was less than 20% or less than 3 per high power field in slide, with the viability above 50%. The biochemical analysis was performed on supernatants obtained after centrifugation. NO - 2/NO - 3 in sputum was tested by Griess reaction, while the eosinophil cationic protein (ECP) in sputum was determined by florescent enzyme immunoassay. Serum NO - 2/NO - 3 and pulmonary function, including the forced expiratory volume in one second (FEV1.0) and percent of the predicated FEV1.0 (FEV1.0%) were also tested synchronously. Patients in Group Ⅲ received systemic steroid via an oral or intravenous route and after 7-10 days of treatment, all parameters were repeated and compared with that before the treatment. Results The median concentrations of sputum NO - 2/NO - 3 in GroupsⅠ, Ⅱ, and Ⅲ were 84.85, 130.71, and 135.81 μmol/L, respectively, all significantly higher than that in controls (63.19 μmol/L) . In addition, those of Groups Ⅱ and Ⅲ were significantly higher than that of Group Ⅰ. No significant difference was found between that of patients in Groups Ⅱ and Ⅲ. Moreover, the levels of NO derivatives in sputum were closely correlated with the degree of airflow obstruction and sputum ECP levels in patients with asthma at remission ( r = -0.587, P <0.05; r =0.535, P <0.01 respectively) and exacerbation ( r =-0.485, P <0.05; r =0.563, P <0.05 respectively). There was no significant correlation between serum and sputum NO - 2/NO - 3, also no significant correlation between that in serum and the degree of airflow obstruction. A significant decrease of median concentration of sputum NO - 2/NO - 3 was observed after the systematic steroid treatment in asthmatic patients with moderate to severe attack (135.81 vs 92.49 μmol/L) with the improvement of pulmonary function, but it was still significantly higher than that of the controls. Conclusion The NO - 2/NO - 3 in sputum may be a useful marker for monitoring the state of airway inflammation and assessing the therapeutic efficacy.
