This test is useful for investigating possible disorders of mitochondrial metabolism, when used in conjunction with CSF lactate, collected at the same time, to determine the lactate-to-pyruvate ratio.
Evaluating patients with neurologic dysfunction and normal blood lactate-to-pyruvate ratios.
A low L:P ratio (disproportionately elevated pyruvic acid) may indicate an inherited disorder of pyruvate metabolism. Defects of the pyruvate dehydrogenase complex result in L:P ratios below 10.
The L:P ratio is characteristically normal in other patients. An artifactually high ratio can be found in acutely ill patients.