Estudo da correlação entre tomografia computadorizada do tórax de alta resolução (TCAR), tomografia por emissão de pósitrons (PET/CT) e mediadores de inflamação da doença intersticial pulmonar na esclerose sistêmica

Abstract

Interstitial lung disease (ILD) is the leading cause of morbidity and mortality in systemic sclerosis (ILD-SSc) and its inflammatory activity is crucial in clinical decision making regarding the beginning or modification of therapy. However, there is no available methods with enough accuracy to predict the presence of inflammatory activity in this condition. In this regard, PET/CT has being used in other inflammatory diseases but has not been fully validated in ILD-SSc. The objectives of this study were to assess the potential role of PET/CT findings to predict inflammatory activity in lung parenchyma and its correlation with, tomographic patterns (CT), clinical and pulmonary function tests (PFT) and serum levels of inflammatory mediators in ILD of SSc patients. A cross-sectional study involving 23 ILD-SSc patients was undertaken using 18F-FDG PET/CT, HRCT, chemokines levels, clinical and PFT variables. NSIP was the predominant pattern in 19 patients (82.6%) in CT. Honeycombing areas had higher SUV values (max: 1.95, mean: 0.92) although not different to the others (p = 0.85). sTNFR1, sTNFR2, CCL2, CXCL10 had higher levels as compared to controls. CCL2 levels – a marker of fibroblast activity - were correlated with the presence of ground-glass areas (p = 0. 007). According to these findings inflammatory activity is present in all CT patterns in ILD-SSC. The correlation between serum CCL2 and ground-glass pattern suggests the presence of fibroblast activity besides of other cells. This finding may support the development of novel therapies directed to this cellular target.