[Correlation between serum interleukin-38 and acute exacerbation of chronic obstructive pulmonary disease with pulmonary embolism].

Objective: To investigate the correlation between serum interleukin-38 (IL-38) and acute exacerbation of chronic obstructive pulmonary disease (AECOPD) with pulmonary embolism (PE). Methods: The 94 patients with AECOPD admitted to Tianjin Chest Hospital from August 2015 to April 2018 were suspected of PE. They were divided into two groups based on CT pulmonary angiography (CTPA) and color Doppler ultrasound of lower extremity veins: 39 cases in PE group and 55 cases in Non-PE group. The general data and laboratory examination results of these subjects were recorded. Serum IL-38 was measured by double antibody enzyme-linked immunosorbent assays (ELISA). The between-group differences of above parameters were analyzed. Pearson correlation or Spearman rank correlation was used to analyze the association of IL-38 with each variable in AECOPD patients. Binary Logistic regressions were conducted to determine the risk factors of AECOPD with PE. ROC curve was used to assess the value of serum IL-38 in predicting AECOPD with PE. Results: The serum level of IL-38 was lower in PE group than in Non-PE group [46.3 (33.1, 58.1) vs 61.5 (46.6, 72.5) ng/L, P<0.05]. Correlation analysis showed that serum IL-38 levels were negatively correlated with C reactive protein and fibrinogen in patients with AECOPD (r=-0.38,-0.29, all P<0.05). Binary Logistic regressions showed that lower serum IL-38 level was a risk factor of AECOPD with PE (OR=0.78, 95%CI: 0.61-0.94, P<0.05). The area under the ROC curve was 0.74 (95% CI: 0.63-0.84, P<0.05). When cutoff value of serum IL-38 was 52.1ng/L, the sensitivity was 70.9% and the specificity was 69.2% respectively. Conclusion: IL-38 could relieve the hypercoagulability by inhibiting inflammation in patients with AECOPD and could act as a predictor of AECOPD with PE.