Reference values for cerebrospinal fluid glutamine concentration in infants.

We measured cerebrospinal fluid glutamine concentration in a reference group of 85 newborn to 30-month-old infants. All of the spinal taps were performed for the diagnosis of illnesses unrelated to hyperammonemia or hepatic encephalopathy. We also analyzed samples from patients with meningitis or cerebral hemorrhage, or who were receiving total parenteral nutrition. The mean glutamine concentration in cerebrospinal fluid in the reference group was somewhat lower than values reported for older children and adults. Values were significantly higher in patients with meningitis or cerebral hemorrhage and in those infants receiving total parenteral nutrition.