Serum S1P level in interstitial lung disease (ILD) is a potential biomarker reflecting the severity of pulmonary function.

sphingosine-1-phosphate (S1P), a naturally occurring sphingolipid, has been involved in pulmonary interstitial remodeling signaling. However, no study has examined its clinical merits for interstitial lung disease (ILD). This study aimed to investigate the serum level of S1P in ILD patients and its clinical correlation with the severity of disease in the two main types of ILDs: the IPF and the CTD-ILD patients. This retrospective observational pilot study included 67 ILD patients and 26 healthy controls. These patients were stratified into the IPF group (35) and the CTD-ILD group (32). The severity of ILD was evaluated through pulmonary function indicators and the length of hospital stay. Serum S1P level was statistically higher in ILD patients than in health control (p = 0.002), while the Serum S1P levels in CTD-ILD and IPF patients were comparable. Serum S1P level further showed statistically negative correlation with pulmonary function indexes (TLC% pred, FVC% pred and FEV1% pred) and positive correlation with length of hospital stay (r = -0.38, p = 0.04; r = -0.41, p = 0.02, r = -0.37, p = 0.04; r = 0.42, p = 0.02, respectively) in CTD-ILD patients, although serum S1P level was not significantly correlated with inflammatory indexes. The IPF patients failed to exhibit a significant correlation of serum S1P level with pulmonary function and length of hospital stay. Serum S1P level might be a clinically useful biomarker in evaluating the severity of CTD-ILD patients rather than IPF patients.

Ding F ，Wang Z ，Wang J ，Ma Y ，Jin J ... -  《BMC Pulmonary Medicine》

Serum Rcn3 level is a potential diagnostic biomarker for connective tissue disease-associated interstitial lung disease and reflects the severity of pulmonary function.

Although reticulocalbin 3 (Rcn3) has a critical role in alveolar epithelial function as well as in pathogenesis of pulmonary fibrosis, no study has yet examined its diagnostic and prognostic values for interstitial lung disease (ILD). This study aimed to evaluate Rcn3 as a potential marker in differential diagnosis of idiopathic pulmonary fibrosis (IPF) and connective tissue disease-associated interstitial lung disease (CTD-ILD) and in reflecting the severity of disease. This was a retrospective observational pilot study included 71 ILD patients and 39 healthy controls. These patients were stratified into IPF group (39) and CTD-ILD group (32). The severity of ILD was evaluated through pulmonary function test. Serum Rcn3 level was statistically higher in CTD-ILD patients than that in IPF patients (p = 0.017) and healthy controls (p = 0.010). Serum Rcn3 further showed statistically negative correlation with pulmonary function indexes (TLC% pred and DLCO% pred) and positive correlation with inflammatory indexes (CRP and ESR) (r =  - 0.367, p = 0.039; r =  - 0.370, p = 0.037; r = 0.355, p = 0.046; r = 0.392, p = 0.026, respectively) in CTD-ILD patients rather than IPF patients. ROC analysis demonstrated that serum Rcn3 had superior diagnostic value for CTD-ILD and a cutoff value of 2.73 ng/mL had a sensitivity of 69%, a specificity of 69% and an accuracy of 45% for diagnose of CTD-ILD. Serum Rcn3 levels might be a clinically useful biomarker in screening and evaluating CTD-ILD.

Ding F ，Yang L ，Wang Y ，Wang J ，Ma Y ，Jin J ... -  《BMC Pulmonary Medicine》

Acute exacerbations of fibrosing interstitial lung disease associated with connective tissue diseases: a population-based study.

Cao M ，Sheng J ，Qiu X ，Wang D ，Wang D ，Wang Y ，Xiao Y ，Cai H ... -  《BMC Pulmonary Medicine》

Serum KL-6 levels reflect the severity of interstitial lung disease associated with connective tissue disease.

Lee JS ，Lee EY ，Ha YJ ，Kang EH ，Lee YJ ，Song YW ... -  《-》

[Characteristics and clinical significance of pulmonary function test and KL-6 in ASSD-ILD and IPF].

Sun D ，Cheng Z ，Jiang TC ，Li PF ，Jia LQ ，Wang TT ，Zheng CP ，Li Y ，Duo MJ ... -  《-》