系统性硬化症合并肺间质病变患者血清中KL-6及SP-D水平与肺功能参数的关系

目的 通过检测系统性硬化症（SSc）合并间质性肺病（ILD）患者血清中肺表面活性蛋白D（SP-D）和Ⅱ型肺泡细胞表面抗原（KL-6），分析其与患者临床症状、免疫学指标及肺功能的相关性，探索诊断ILD的新血清学指标。方法 收集安徽省立医院风湿免疫科2013年1～10月住院及门诊确诊为SSc患者35例，其中SSc-ILD组20例，SSc-非ILD组15例，正常对照组选择年龄、性别相匹配的19例我院门诊健康体检者。采用ELISA法检测所有研究对象血清中SP-D和KL-6的水平。比较SSc组、SSc-ILD组、SSc-非ILD组、正常对照组血清样本中SP-D和KL-6的水平，分析上述血清学指标与肺功能指标的相关性。结果 ①血清中KL-6、SP-D水平SSc-ILD组患者高于正常对照组，差异有统计学意义（P<0.05），SSc-ILD组显著高于SSc-非ILD组（P<0.05），而SSc-非ILD组与正常对照组比较，差异无统计学意义（P>0.05）；② SSc患者血清中KL-6、SPD与肺功能指标用力肺活量（FVC）、一氧化碳弥散量（DLCO）、肺活量（VC）呈负相关（P<0.05），其中KL-6与血沉（ESR）、C反应蛋白（CRP）、IgG、IgA、IgM 无相关性，SP-D与IgG、IgM呈负相关（P<0.05），与ESR、CRP、IgA无相关性。结论 SSc合并ILD患者血清中KL-6、SP-D水平显著升高，SSc患者血清中KL-6、SP-D水平与肺功能指标呈负相关；血清KL-6、SP-D可能作为诊断与评估SSc-ILD病情严重程度的血清学指标。

Association between serum KL-6 and SP-D levels and lung function parameters in patients with systemic sclerosis combined with interstitial lung disease

Objective To examine the serum levels of pulmonary surfactant protein-D(SP-D) and Krebs Von den Lungen-6(KL-6) in the patients with systemic sclerosis (SSc) combined with interstitial lung disease (ILD), and to analyze their correlations with the clinical signs, immunological indexes and lung function in search for novel serum diagnostic biomarkers of ILD. Methods From Jan 2013 to Oct 2013, thirty-five cases of SSc patients diagnosed in our hospital were collected. The serum KL-6 and SP-D levels of all research objects, including 15 SSc-non ILD patients, 20 SSc-ILD patients and 19 age- and sex-matched healthy controls, were examined by ELISA. The serum levels of KL-6 and SP-D among the SSc group, the SSc-ILD group, the SSc-non ILD group and the control group were compared, and the correlations between above serological results and pulmonary function indexes were analyzed. Results The serum KL-6 and SP-D levels in the SSc-ILD group were significantly higher than those in the SSc-non ILD and control groups (P<0.05). However, no significant difference was found between those SSc-non ILD patients and healthy controls (P>0.05). In the SSc patients, their pulmonary function results of diffusing capacity of the lung for carbon monoxide (DLCO), forced vital capacity (FVC) and vital capacity (VC) were negatively correlated with the serum KL-6 and SP-D levels. And the SP-D levels were negatively correlated with the IgG and IgM levels, irrelevant to the erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and IgA levels. No correlation was found between the KL-6 levels and the ESR, CRP, IgG, IgA and IgM levels. Conclusion The serum KL-6 and SP-D levels of SSc patients combined with ILD increase significantly, and are negatively correlated with the lung function indexes. The serological indexes of serum KL-6 and SP-D levels may be helpful to diagnose and assess the disease severity of those SSc-ILD patients.