Sample type | 24 hr urine (acidified) |
Container | 24 hr urine container with 50 mL hydrochloric acid |
Precautions |
Elevated by dietary walnuts, bananas, tomatoes, avocado, kiwi fruit, pineapple, plantain, plums, pecan nuts. Avoid for 3-4 days prior to starting urine collection. Click here for patient information sheet for urine collection |
Minimum volume | 2 mL |
Reference range | ≤ 42 μmol/24 h |
Turnaround time | 14 days |
Method | Liquid chromatography-tandem mass spectrometry |