High-resolution Computed Tomography Imaging Features,Risk And Prognostic Factors Of Systemic Sclerosis-associated Interstitial Lung Disease

Objectives 1.To analysis the epidemiology character,clinical and imaging features,risk factors and survival rates of systemic sclerosis-associated interstitial lung disease(SSc-ILD);2.To compare SSc-ILD with RA-ILD and SLE-ILD in terms of HRCT imaging features and extent,and to make recommendations for effective treatment of CTD-ILD and assessment of prognosis.Methods A total of 244 SSc patients(167 with SSc-ILD),54 with RA-ILD and 131 with SLE-ILD who were hospitalized in Guangdong Provincial People’s Hospital during the 10-year period from January 2010 to December 2019 were collected in this study.(1)We compared and analyzed the differences in clinical characteristics between SSc combined with and without ILD,to analyze the risk factors of ILD in SSc patients.(2)The chest HRCT manifestations and pulmonary function examination results of the three CTD-ILDs were analyzed to compare and summarize the characteristics of the three CTD-ILDs.(3)We analysed the congruence between HRCT pattern and pathology pattern and the relationships between the four HRCT evaluating methods presented with PETs.(4)Survival curves were plotted using Kaplan-Meier curves,and searched the independent prognostic factors of SSc-ILD by cox regression analysis.Data were processed using SPSS 25.0 statistical software,and P < 0.05 was defined as a statistically significant difference.Results 1.We collected 244 patients with SSc in this study,included 59 males and 185 females.The male to female ratio was approximately 1:3.1,and there were 68.4% of patients had combined interstitial lung disease,and the proportion of interstitial lung was higher in patients with dc SSc than lc SSc.Raynaud’s phenomenon,finger sclerosis,and digital ulcers were more common in ILD patients than in non ILD group.Dyspnea was the most common with in patients with interstitial lung disease,followed by cough,cough,and chest tightness。 Gastrointestinal involvement,age of onset and positive anti-Scl-70 antibody were the risk factors for the development of interstitial lung disease in SSc.2.The most common presentation on HRCT were ground-glass opacities,followed by interlobular septal thickening,reticular opacities,intralobular interstitial thickening,honeycomb cysts and traction bronchiectasis.The most common pattern in SSc-ILD was NSIP,accounted for 71.6%;secondly was UIP,accounted for 25.9%,a few patients presented consistent with LIP.In RA-ILD,UIP was the most common pattern,followed by NSIP and the vast majority of SLE-ILD showed NSIP pattern.SSc had a higher proportion of interstitial lung disease than RA and SLE,with wider extent of lesion involvement,higher HRCT score,and more common impaired pulmonary ventilation and diffusion function.3.There was no difference in ILD pattern between HRCT and pathology,and the two methods revealed a high congruence.The four HRCT evaluating methods presented in this study(the staging method,the severity staging system,Goldin scoring method and Kazerooni scoring method)showed good correlation with each other and also had significant relationships with PETs.4.The results of this study suggested that older age at onset and positive anti-Scl-70 antibody were the risk factors for progression of SSc-ILD,while positive anti-SSA antibody was a protective factor;independent predictors of death in SSc-ILD patients were higher oxygen concentration during hospitalization,higher AST,higher CRP,while early diagnosis is a protective factor of ILD.Conclusion 1.Older age at onset,anti-Scl-70 antibody positivity,and GI tract involvement are independent risk factors for the development of ILD in SSc patients.And older age at onset and anti-Scl-70 antibody positivity are independent risk factors for the progression of SSc-ILD.2.HRCT imaging typing of the chest in ILD was in good agreement with the pathological typing of lung puncture biopsy,and had the advantages of being non-invasive,safe and reproducible,which can replace lung biopsy as the "gold standard" for the diagnosis and staging of ILD.The four HRCT assessment methods had good correlation with lung function and had better specificity than pulmonary function in the diagnosis of ILD,and can be used as an important test for ILD screening and disease assessment and follow-up.3.SSc-ILD has a higher prevalence and more extensive lesions than RA-ILD and SLE-ILD,with a higher chest HRCT score and a worse survival prognosis,and UIP is not the only factor for poor prognosis;primary disease and lesion involvement also affect prognosis.4.Early detection and early treatment can improve the prognosis of patients,and it is meaningful to manage SSc-ILD patients in groups according to the different time of ILD onset.