Plasma citrulline kinetics and prognostic value in critically ill patients

Multiple organ failure is a leading cause of death in critically ill patients and could be secondary to early gut ischemia. Plasma citrulline is a biomarker of enterocyte mass, and critically ill patients may have enterocyte mass reduction. The objectives of this study were to assess plasma citrulline kinetics and its prognostic value in critically ill patients.

This prospective observational study included adults without small bowel disease and without chronic renal failure consecutively admitted to a single intensive care unit. Prognostic variables as well as plasma citrulline concentrations were studied at admission, 12, 24, 48 h, and the 7th day after admission. Univariate and multivariate analyses including plasma citrulline (0-10, 11-20, and >20 micromol l(-1)) and other variables were performed.

Sixty-seven patients were included, and the 28-day mortality was 34%. During the 1st day mean plasma citrulline decreased from 18.8 to 13.5 micromol l(-1). Low plasma citrulline at 24 h was associated with low plasma glutamine and arginine (p = 0.01 and 0.04), and high plasma CRP concentration, nosocomial infection rate, and 28-day mortality (p = 0.008, 0.03, and 0.02, respectively). In multivariate analysis plasma citrulline < or = 10 micromol l(-1) at 24 h and SOFA score > or =8 at 24 h were associated with 28-day mortality(odds ratios 8.70 and 15.08).

In critically ill patients, low plasma citrulline at 24 h is an independent factor of mortality and could be a marker of acute intestinal failure.