The purpose of this study was to assess the association between the serum levels of aminoterminal propeptide of type III procollagen (PIIINP) and carboxyterminal propeptide of type I procollagen (PICP) with disease activity and damage in systemic lupus erythematosus (SLE). Thirty-three patients with SLE were compared with 31 controls. The assessment in SLE included disease activity indices (SLEDAI, MEX-SLEDAI) and damage index (SLICC/ACR). PIIINP and PICP were measured by radioimmunoassay. Compared with controls, mean levels of PIIINP were higher in SLE (2.9+/-1.8 vs. 1.8+/-1.2, P=0.006). PICP was also increased in SLE versus controls (163+/-94 vs. 102+/-62, P=0.007). PIIINP was correlated with SLICC/ACR (r=0.33, P=0.048). No correlation was observed between PICP and PIIINP with other clinical or therapeutic variables. These preliminary data suggests a role of PIIINP as a marker for chronic damage. Follow-up studies are required to evaluate its utility in predicting future damage.