Plasma citrulline in the critically ill: intriguing biomarker, cautious interpretation

In a recent issue of Critical Care, Poole and colleagues found that plasma citrulline concentration and glucose absorption were reduced in 20 critically ill patients compared with 15 controls; however, the authors found no correlation between these two variables. This study highlights the question of the accuracy of plasma citrulline for assessing small bowel function in critically ill patients. Future studies should take into account the type of intestinal failure considered, the particular metabolism of citrulline, the time of plasma citrulline measurement, as well as the range of citrullinemia considered.