Carnitine homeostasis in the organic acidurias.

The detection of acylcarnitines by FAB-MS in human physiological fluids has added another valuable diagnostic tool for the recognition of specific metabolic diseases. The newly developed technique of FAB-MS/MS, which embodies the principles of tandem mass spectrometry, affords a quantum leap in specificity, enabling the detection and quantification of acylcarnitines in concentrations well within the physiological ranges in urine, blood and tissue. The therapeutic use of L-carnitine appears to offer protection against the harmful consequences of catabolism. A reduction in the number of clinical episodes requiring hospitalization has been observed in most cases. When such occurrences have necessitated intravenous fluids, the addition of L-carnitine to the IV infusate has led to dramatic reduction in recovery times. It has also been shown that there is no discernable toxicity associated with carnitine therapy, even under high-dose IV conditions.