ObjectiveTo determine the diagnostic value of serum KL-6 level in patients with interstitial lung diseases (ILD). MethodsAll the ILD patients enrolled were hospitalized from April 2013 to April 2014. Patients with other pulmonary diseases and healthy subjects were chosen as control groups simultaneously. Serum KL-6 concentrations were measured by chemiluminescent enzyme immunoassay. The association with serum KL-6 level and pulmonary function was analyzed. ResultsThere were 149 ILD patients, 155 patients with other pulmonary diseases, and 64 healthy subjects. The average serum levels of KL-6 were (1 801.86±2 831.36) U/mL, (267.00±124.41) U/mL, (201.28±81.18) U/mL in the patients with ILD, the patients with other pulmonary diseases and the healthy controls, respectively. The sensitivity and the specificity of the serum KL-6 for the diagnosis of ILD was 83.89% and 92.24% respectively when the cut-off level was set at 500 U/mL. The Kappa value was 0.767 (P < 0.001). The best cut-off value of KL-6 was 469.5 U/mL. Serum KL-6 levels in the patients with ILD were significantly higher compared with the patients with chronic obstructive pulmonary disease, pneumonia, tuberculosis, bronchiectasis and the healthy controls, respectively (all P < 0.001). The KL-6 levels in the pulmonary alveolar proteinosis patients were significantly higher compared with the patients with cryptogenic organizing pneumonia (COP), the patients with idiopathic pulmonary fibrosis (IPF) and the patients with connective tissue disease (CTD-ILD) (all P < 0.001). While the KL-6 concentration in IPF and CTD-ILD were significantly higher than that in COP (P=0.003 and P=0.008, respectively). Significant negative correlations were found between the levels of serum KL-6 and vital capacity as a percentage of the predicted value, forced vital capacity as a percentage of the predicted value, forced expiratory volume in one second as a percentage of the predicted value and carbon monoxide diffusing capacity as a percentage of the predicted value (all P < 0.001). Follow-up study showed the levels of serum KL-6 were consistent with clinical efficacy. ConclusionSerum KL-6 level is a reliable serum marker for ILD, and is related with the severity of disease and clinical efficacy.
Objective To analyze the risk factors of invasive pulmonary aspergillosis (IPA) in patients with interstitial pneumonia. Methods The clinical data of 770 cases of interstitial pneumonia admitted between December 2010 and August 2015 were collected. Among them, 46 cases were combined with IPA and 724 cases were not ombined with IPA. The clinical data was analyzed to explore the risk factors of IPA in patients with interstitial pneumonia. Results Univariate analysis showed that in the aspects of age (t=3.348, P=0.001), serum albumin level (t=8.381, P < 001), broad-spectrum antibiotic used within 3 months (χ2=87.157, P < 001), long-term administration of glucocorticoid (χ2=57.462, P < 001), long-term administration of immunosuppressive agents (χ2=31.715, P < 001), imaging in UIP type (χ2=20.632, P < 001), diabetes mellitus (χ2=9.737, P=0.002) and heart failure (χ2=9.300, P=0.002), there were significant differences between two groups. After multivariate logistic regression analysis, broad-spectrum antibiotic used within 3 months (OR=4.773, P < 001), long-term administration of glucocorticoid (OR=9.195, P < 001), long-term administration of immunosuppressive agents (OR=2.662, P=0.046), imaging in UIP type (OR=5.725, P < 001), and diabetes mellitus (OR=3.847, P=0.003) were found to be the risk factors of IPA in patients with interstitial pneumonia. Serum albumin level was negatively correlated with the occurrence of IPA in patients with interstitial pneumonia. Conclusions Various factors contribute to the occurrence of IPA in patients with interstitial pneumonia. Miscellaneous appropriate measures should be taken to reduce the incidence of IPA.