Comparison of a new, modified lung ultrasonography technique with high-resolution CT in the diagnosis of the alveolo-interstitial syndrome of systemic scleroderma

Aims: Pulmonary fibrosis is the main cause of mortality in patients with Systemic Scleroderma (SSc). This study was performed to investigate the utility of modified trans-thoracic ultrasound (TTUS) scoring system according to the comet tail sign (B-line artifacts) and to compare it with high-resolution computed tomography (HRCT) findings in patients with SSc and pulmonary involvement. Patients and method: Seventy subjects with SSc diagnosed according to the American College of Rheumatology criteria were enrolled. All subjects underwent HRCT followed by TTUS for comet tail sign detection in order to predict the degree of lung fibrosis. The modified TTUS assessment was performed at 10 intercostals spaces level. Results: A significantly positive correlation between TTUS and the severity of pulmonary involvement (Spearman's correlation coefficient= 0.695, P < 0.001), (LR=74.36, P<0.001) was found. When compared with HRCT as the gold standard method, the sensitivity, specificity, positive and negative predictive value of TTUS was 73.58%, 88.23%, 95.12% and 51.72% respectively. Kappa values for the intra-observer modified TTUS assessment was 0.838. Conclusions: Our study showed that the modified TTUS comet tails scoring system could be useful in the assessment of the pulmonary involvement in patients with SSc.