,39 Of note, a well-designed study including patients with IPF, RA-ILD, and other ILDs showed that among patients with increased MMP-7, the absence of concomitant rise in SP-D and osteopontin was indicative of a non-IPF or non-UIP ILD.27 The gene discussed is SFTPD; the disease is idiopathic pulmonary fibrosis.