Collect: 24-hour urine. Refrigerate during collection. Also acceptable: Random urine.
Specimen Preparation: Adjust pH to 1 by adding 6M HCl (approximately 10 mL HCl/24-hour specimen based on normal adult output of 1000-2000 mL/24 hours. Pediatric specimens will require less than 10 mL to reach the correct pH). Record total volume and collection time interval on transport tube and test request form. Transfer 4 mL aliquot of urine from a well-mixed 24-hour collection to an ARUP Standard Transport Tube. (Min: 0.5 mL)
Storage/Transport Temperature: Refrigerated.
Unacceptable Conditions: Specimens containing preservatives other than HCl. Specimen submitted in metal containers.
Stability (collection to initiation of testing): Ambient: 1 week (if acidified); Refrigerated: 1 week; Frozen: 1 year