10 mL random urine, after collection add 6N HCL to maintain a pH below 3. Submit in a sterile screw capped container shipped ambient.

Note: 1. Urine without preservative is acceptable if pH is below 6 and shipped frozen.

         2. Dietary Instructions:

             - Patient should avoid food high in indoles: avocado, banana, tomato, plum, walnut, pineapple, and eggplant.

             - Patient should also avoid tobacco, tea and coffee three days prior to specimen collection.