10 - 14 days
Patient should be fasting 10-12 hours prior to collection of specimen. Antacids or other medications affecting stomach acidity or gastrointestinal motility should be discontinued, if possible, for at least 48 hours prior to collection.
Collect specimen in red top or SST. Spin and aliquot into a screw capped plastic tube. Send to Specimen Processing frozen
Test is sent to Mayo Clinic Laboratories; performed by Interscience Institute