Porphyrins, Quantitative, Random Urine

Casandra

Casandra Test Code LC87270Version 1 (DRAFT)

Performing Lab

Lab LabcorpLab Test ID 120980CPT Code 84120

Porphyrins, Quantitative, Random Urine

Also known as: Coproporphyrin, Uroporphyrin

Clinical Use

Order Test

Use

Urine porphyrins are useful for the evaluation of cutaneous photosensitivity to exclude porphyria cutanea tarda (PCT). Evaluation of neurologic and/or psychiatric symptoms associated with acute porphyrias, such as acute intermittent porphyria (AIP), requires urine porphobilinogen (PBG) testing. Refer to Porphobilinogen (PBG), Quantitative, Random Urine [003065].

Special Instructions

Refrigerate the specimen and protect it from light during transport. Aliquot into an amber plastic transport tube (LabCorp No. 23598) with an amber cap. If unavailable, cover the tube with aluminum foil and secure it with tape. Clearly label the tube with the patient's name.

Limitations

Results may be affected by the loss of specimen integrity due to exposure to light or lack of refrigeration. Acidic pH or the presence of acid preservatives can compromise the sample quality. The test does not substitute for urine porphobilinogen (PBG) testing when evaluating symptoms associated with acute porphyrias.

Test Details

Methodology

Chromatography (High-pressure liquid chromatography (HPLC) with fluorometric detection)

Biomarkers

6 targets

Coproporphyrin (CP) ICoproporphyrin (CP) IIIHeptacarboxylporphyrins (7-CP)Hexacarboxylporphyrins (6-CP)Pentacarboxylporphyrins (5-CP)Uroporphyrins (UP)

LOINC Codes

Result Codes

11228-4
2407-5
27400-1
11221-9
9343-5
9345-0

Result Turnaround Time

3-5 days

Specimen

Urine

Volume

2 mL

Minimum Volume

1.5 mL

Container

12-mL amber plastic transport tube without preservative

Collection Instructions

Transfer required aliquot into a LabCorp amber plastic transport tube with amber cap (LabCorp No. 23598). If unavailable, cover tube completely with aluminum foil and secure with tape. Label with patient's name.