Antimicrobial effects of arginine and nitrogen oxides and their potential role in sepsis.

! 2006 Lippincott Williams & Wilkins 1363-1950 Introduction The amino acid arginine (ARG) (L-amino-5-guanidinovaleric acid) has traditionally been classified as nonessential for adults and children [1] because the human body can synthesize it. ARG, however, is essential for growth and development in many mammals and can be considered non-essential only in fully grown adult animals [2]. More recent data in humans now indicate that ARG can be considered a ‘conditionally essential’ amino acid because, under certain clinical conditions and disease states associated with metabolic stress, endogenous synthesis cannot keep up with increased demand. This seems to be the case particularly in critical illness and sepsis [3,4!]. Sources of ARG other than de-novo synthesis are protein catabolism and dietary intake. In healthy individuals, normal dietary ARG intake is approximately 5 g per day [2]. Fish and nuts are particularly ARG-rich foods [5].