Urine organic acids are separated by gas chromatography and identified by mass spectrometry. This test identifies abnormalities in over 100 different clinically significant organic acids. Disorders detected by this test include methylmalonic acidemia, propionic acidemia, isovaleric acidemia, Canavan disease and many others. Because organic acid profiles can be influenced by diet, medications and clinical status, it is important to provide this information to the laboratory for optimal interpretation of results.