Interstitial lung disease (ILD) is a frequent complication in progressive systemic sclerosis (SSc), being present in 25% to 90% of cases. To evaluate whether serum levels of procollagen typei and iii aminoterminal propeptide (PINP and PIIINP) correlate with severity and patterns of ILD in Mexican women with SSc. Thirty three SSc patients were assessed for disease characteristics and anti-topoisomerase antibodies (topoi), and also underwent pulmonary function tests and high-resolution computed tomography (HRCT). Nineteen patients had ILD+SSc, and 14 had no lung involvement (no ILD-SSc); data were compared with those from 45 healthy controls. PINP and PIIINP were assessed in all 3 groups. Patients with SSc had higher PINP and PIIINP vs controls (P=.001, P