探讨涎液化糖链抗原-6（kerbs von den lungen-6, KL-6）在老年特发性肺纤维化（idiopathic pulmonary fibrosis, IPF）诊断和治疗中的评估价值。

选取2018年7月至2019年11月牡丹江医学院附属红旗医院收治的普通型间质性肺炎型IPF患者68例，其中老年患者36例（老年IPF组）、非老年患者32例（非老年IPF组），另择同期老年健康体检者32例（老年健康组）作为对照。采用酶联免疫吸附试验测定血清KL-6表达水平，记录所有IPF患者的肺功能指标，并对其普通型间质性肺炎病变程度进行评估。比较各组血清KL-6的表达水平及肺部高分辨率CT（HRCT）评分，分析KL-6与肺功能指标和肺部HRCT评分的相关性。多组间的比较采用方差分析（进一步两两比较采用LSD-t检验）或秩和检验，计数资料的比较采用χ²检验；相关关系采用Pearson相关分析或Spearman秩相关分析。

3组患者KL-6表达水平的差异有统计学意义（F=63.425，P<0.05），其中老年IPF组明显高于非老年IPF组和老年健康组（P<0.01）。ROC曲线显示，KL-6诊断老年IPF的临界值为516.21 U/ml，此时敏感度和特异度最高，分别为94.4%和87.5%。无论是老年IPF组还是非老年IPF组，急性加重患者血清KL-6表达水平均明显高于稳定患者（t=2.843、2.215，P<0.05或0.01）；老年IPF组中急性加重患者血清KL-6表达水平均明显高于非老年IPF组（t=2.657，P<0.05）。相关分析显示，无论是68例IPF患者还是老年IPF组患者，其KL-6水平与HRCT评分均呈正相关（r=0.748、0.699，P<0.01）。老年IPF患者血清KL-6表达水平与部分限制性通气功能和弥散功能指标呈负相关（r=-0.515、-0.393、-0.384，P<0.05）。

血清KL-6对诊断IPF有一定临床意义，尤其对于老年患者具有较高的诊断敏感度及特异度，且与疾病严重程度及治疗效果呈现一定相关性。

To explore the evaluation value of kerbs von den lungen-6 (KL-6) in the diagnosis and treatment of elderly patients with idiopathic pulmonary fibrosis (IPF).

68 IPF patients with usually interstitial pneumonia admitted to Hongqi Hospital of Mudanjiang Medical College from July 2018 to November 2019 were selected, including 36 elderly IPF patients (elderly IPF group) and 32 non-elderly patients (non-elderly IPF group), another 32 elderly health checkups (the elderly healthy group) were selected as the control. Enzyme-linked immunosorbent assay was used to determine the expression level of serum KL-6, to record the pulmonary function indexes of all IPF patients, and to evaluate the pathological changes of their usually interstitial pneumonia. The serum KL-6 expression levels and lung high-resolution CT (HRCT) scores were compared in each group, and the correlations between KL-6 and lung function indicators and lung HRCT scores were analyzed. The comparison between multiple groups was performed by analysis of variance (the LSD-t test was used for further pairwise comparisons) or the rank sum test, and the comparison of count data was performed by chi square test; correlation analysis was used by Pearson correlation analysis or Spearman rank correlation analysis.

There were statistically significant differences in kL-6 expression levels among the three groups (F=63.425, P < 0.05). The expression level of KL-6 in the elderly IPF group was significantly higher than that of the non-elderly IPF group and the elderly healthy group (P < 0.01). The ROC curve showed that the critical value of KL-6 for diagnosing IPF in the elderly was 516.21 U/ml. At this time, the sensitivity and specificity were the highest, 94.4% and 87.5%, respectively. Regardless of whether the elderly IPF group or the non-elderly IPF group, the serum KL-6 expression level of acute exacerbation patients was significantly higher than that of stable patients (t=2.843, 2.215, P < 0.05 or 0.01). The expression level of serum KL-6 in patients with acute exacerbations in the elderly IPF group was significantly higher than that in the non-elderly IPF group (t=2.657, P < 0.05). Correlation analysis showed that whether it was 68 IPF patients or elderly IPF patients, their KL-6 levels were positively correlated with HRCT scores (r=0.748, 0.699, P < 0.01). The expression level of serum KL-6 in elderly IPF patients was negatively correlated with some restrictive ventilatory function and diffusion function indexes (r=-0.515, -0.393, -0.384, P < 0.05).

Serum KL-6 has certain clinical significance for the diagnosis of IPF patients, especially for elderly patients with IPF, it has a high diagnostic sensitivity and specificity, and it has a certain correlation with the severity of the disease and the treatment effect.