Type III procollagen peptide in the adult respiratory distress syndrome. Association of increased peptide levels in bronchoalveolar lavage fluid with increased risk for death.

OBJECTIVE: To determine whether bronchoalveolar lavage fluid levels of the N-terminal peptide of type III procollagen (procollagen III) are increased in patients with the adult respiratory distress syndrome and, if so, whether increased procollagen III levels in lavage fluid are associated with increased fatality rates.
DESIGN: Prospective cohort study.
SETTING: Intensive care units of a tertiary care hospital affiliated with a medical school. PATIENTS: 117 consecutive patients with the adult respiratory distress syndrome prospectively identified on admission; 6 healthy volunteers served as controls. MEASUREMENTS: Bronchoalveolar lavage fluid procollagen III levels in 117 patients at 3, 7, and 14 days after onset of the adult respiratory distress syndrome (total of 196 lavage samples).
RESULTS: The median procollagen III level was 1.75 U/mL (range, 0 to 13.4 U/mL) in lavage fluid obtained from patients with the adult respiratory distress syndrome. We detected procollagen III levels in lavage fluid from 80% of patients (94 of 117) but not in 6 normal volunteers. The overall fatality rate was 41% (48 of 117 patients). In a univariate analysis, the relative risk (RR) for death was increased in patients with procollagen III levels of 1.75 U/mL or more obtained on day 3 (RR, 2.4; 95% CI, 1.3 to 4.3), day 7 (RR, 2.7; CI, 1.4 to 5.4), and day 14 (RR, 2.7; CI, 1.1 to 6.3). Inclusion of other variables in a multivariate model only minimally decreased the risk associated with increased procollagen III levels.
CONCLUSION: Increased levels of type III procollagen in bronchoalveolar lavage fluid are frequently detected in patients with the adult respiratory distress syndrome and are strongly associated with increased risk for fatal outcome independent of other variables related to fatality in patients with the syndrome.