Abstract:

Objective This study mainly explored the diagnostic value of neutrophil gelatinase⁃associatedlipocalin（NGAL）in chronic obstructive pulmonary disease（COPD）. Methods We collected 97 COPD patientsin respiratory and critical medical departments in the second affiliated hospital of Chongqing medical universityfrom June 2018 to December 2019 as the case group. 50 healthy adults were included as control group. Patientswere further divided into two subgroups：acute exacerbation of chronic obstructive pulmonary disease（AECOPD）and COPD combined community⁃acquired pneumonia（COPD⁃CAP）. Then the patients were divided into 4 sub⁃groups：GOLDⅠ，Ⅱ，Ⅲ，Ⅳ. The serum NGAL level was detected by ELISA method，the basic information andclinical indexes were collected. Single factor analysis was used to identify the factors with significant differencesamong different groups. Then the Spearman correlation between NGAL and other indexes was analyzed. Finally，theROC curve was used to analyze the diagnostic value of NGAL in COPD patients. Results Serum NGAL level ofCOPD⁃CAP patients and AECOPD patients was significantly higher than that of healthy controls，and the serumNGAL level of COPD⁃CAP patients was significantly higher than that of AECOPD patients（P < 0.05）. The NGALlevel in GOLD Ⅲ、Ⅳ group was significantly higher than that in GOLD Ⅱ group（P < 0.05）. Spearman correlationanalysis showed negative correlation between NGAL and FEV1% pred，FVC% pred. ROC survival curves indicatethat NGAL has a high diagnostic value for both AECOPD and COPD⁃CAP. Moreover，NGAL has moderate value ofdistinguishing GOLD Ⅰ Ⅱ from GOLD Ⅲ Ⅳ. Conclusions NGAL plays an important role in the process of COPDacute inflammatory response，meanwhile，NGAL plays a role in classification of lung function severity，indicatingNGAL is correlated with airway remodeling.

Key words: acute exacerbation of chronic obstructive pulmonary disease, community?acquired pneumonia, neutrophil gelatinase?associated lipocalin（NGAL）, inflammatory factor, airway remodeling, GOLD degree