SFTPD and interstitial lung disease: For instance, ppFVC, serum surfactant protein-D levels and the area occupied by interstitial shadows of lung fields on high-resolution CT images were significantly improved in the rituximab group compared with placebo, while the changes in serum KL-6 levels and the percentage of predicted diffusing capacity for carbon monoxide were comparable between the two groups at 24 weeks in patients with SSc-ILD in the DESIRES trial [7].