Investigation Of SP-D Expression And Clinical Significance In Sputum And Serum Of AECOPD Patients

Purpose: Through observing the difference of the level of SP-D in serum and sputumbetween the patients with AECOPD, COPD in the stable phrase and healthy controls, wedescribed the importance of the SP-D expression in aspects of severity and prognosis ofCOPD.Method:86patients with COPD were randomly recruited from the RespiratoryMedicine of The Second Hospital Attached to Jilin University from March2010to March2011. They included43AECOPD patients (classification of GOLD is I-IV) and43COPDpatients in stable phrase.26healthy controls were recruited who did the routine physicalexamination in the respiratory medicine. The serum and induced sputum samples werecollected from all the subjects, and clinical evaluation, lung function detection, lung CTscanning and BODE score were conducted. The SP-D and CRP were measured by usingELISA.Result:(1)There was no difference in age and gender Among three groups.(2)The BMIof the AECOPD and the stable COPD were significantly less than that of healthycontrols(P<0.05).(3)The level of the SP-D, CRP in serum and sputum CRP in AECOPDwere the highest, which were followed by the stable COPD. The healthy controls had thelowest level (P<0.05). On the contrary, the healthy controls had the highest level of SP-D insputum, which were followed by the stable COPD. The AECOPD patients have the lowestlevel (P<0.05). COPD can lead to changes of the expression of SP-D, CRP and otherinflammatory factors, COPD is a chronic systemic inflammatory response disease.(4)Thecorrelation analysis result showed that the level of SP-D and CRP in serum and sputum CRPwere negative associated with FEV1(r=-0.502, P<0.05；r=-0.670, P<0.05；r=-0.567, P<0.05),but the SP-D level in sputum has the significantly positive correlation with FEV1(r=0.692,P<0.05). The heavier degree of pulmonary dysfunction in patients with COPD, the lower value of FEV1and level of SP-D in sputum, the higher levels of SP-D in serum、CRP inserum and CRP in sputum.(5)ROC curve analysis showed that the level of SP-D in sputumhad the higher specificity and sensibility in differentiating the stable COPD from the healthycontrols, and CRP in serum had the higher specificity and sensibility in differentiating acuteexacerbation state from the stable COPD.Conclusion:(1) SP-D level in serum and sputum of COPD patients might not onlyreflect the different periods of the disease but also reflect the Severity of the disease. It canprovide an effective basis for the clinical assessment of treatment efficacy and prognosis.(2)As a biomarker of COPD, SP-D in sputum of COPD patients could lead to the differencesbetween healthy controls and the stable COPD,it had the higher specificity andsensibility.Detecting SP-D level in sputum might not only reflect the speed of decline in lungfunction, but also indicate the oxygen radical level in lung.