Measurement of plasma fibronectin in patients who develop the adult respiratory distress syndrome.

Depletion of plasma fibronectin has been observed in certain clinical conditions predisposing to the adult respiratory distress syndrome and has been associated with cardiopulmonary dysfunction in experimental lung injury. We evaluated prospectively the relationship between plasma fibronectin concentration and the development of the adult respiratory distress syndrome in patients known to be at high risk. Although plasma fibronectin levels in participants at study entry were lower in this population (mean 258 +/- 132 micrograms/ml) than in normal volunteers (461 +/- 127 micrograms/ml, p less than 0.0025), there was no difference between patients who subsequently developed the adult distress syndrome (mean 255 +/- 149 micrograms/ml) and those with similar illness or injury who did not develop the syndrome (260 +/- 126 micrograms/ml). Fibronectin concentration was not further depressed even after development of adult respiratory distress syndrome and did not correlate with degree of pulmonary dysfunction. These data suggest that fibronectin depletion is not an important determinant of respiratory failure in humans. Patients with sepsis syndrome had significantly lower plasma fibronectin levels than those without sepsis (187 +/- 119 micrograms/ml vs. 273 +/- 131 micrograms/ml, p less than 0.05), suggesting a possible role for fibronectin in the pathogenesis of sepsis.