The predictive role of lung ultrasound in progression of scleroderma interstitial lung disease

Lung ultrasound (LUS) correlates with chest high-resolution computed tomography (HRCT) findings in the diagnosis of interstitial lung disease (ILD) in systemic sclerosis (SSc). The aim of this study is to evaluate the predictive value of LUS in the progression of ILD. At baseline, forty-one SSc patients underwent HRCT, LUS for detection of B-lines, and pulmonary function test (PFTs). PFTs were performed also after 12 months to evaluate pulmonary function deterioration. In multiple regression analysis, positive correlation exists between the number of B-lines and HRCT score (r = 0.51, p < 0.05), conversely a negative correlation exists between number of B-lines and carbon monoxide diffusing capacity (DLCO) (r = - 0.49, p < 0.05) and FVC (r = - 0.42, p < 0.05). The number of B-lines significantly (p < 0.05) increased with progression of digital microvascular damage. At 12 months, a positive correlation exists between number of B-lines and delta of DLCO. The ROC curves demonstrated a good accuracy of worsened DLCO prediction for Delta DLCO (0.72, p < 0.05 95% CI 0.56-0.88). The sum of B-lines correlates with the radiological score evaluated by HRCT. We also demonstrate that the number of B-lines can predict the worsening of the ILD. Although HRCT is the gold standard technique for assessing ILD, the LUS could become a useful tool for guiding the use of HRCT.