Test Details
Methodology
High-pressure liquid chromatography (HPLC) with fluorometric detection
Result Turnaround Time
3 - 5 days
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
Test Includes
Coproporphyrins I and III; uroporphyrins; hepatocarboxylporphyrins; hexacarboxylporphyrins; pentacarboxylporphyrins
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].
For initial evaluation of porphyrias. Use Porphyrins, Quantitative, 24-Hour Urine [003194] to follow up random urine abnormal results.
Limitations
See Porphyrins, Quantitative, 24-Hour Urine [003194].
Custom Additional Information
Excess urinary porphyrin excretion, or porphyrinuria, results from inhibition of key enzymatic steps in such clinical conditions as genetic deficiencies in heme production enzymes, hepatitis, renal disease, and erythroid disease, as well as by heavy metal inhibition of heme enzyme synthesis.1 Both in experimental animals and in humans exposed to heavy metals, elevated levels of porphyrins have been found in urine.1
Specimen Requirements
Specimen
Urine (random); protected from light
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 amber transport tubes are unavailable, cover transport tube completely, top and bottom, with aluminum foil. Identify specimen with patient's name directly on the amber transport tube and on the outside of the aluminum foil. Secure with tape.) Specimen must be kept refrigerated during transport.
Stability Requirements
Temperature | Period |
|---|---|
Room temperature | Unstable |
Refrigerated | 7 days |
Frozen | 14 days |
Freeze/thaw cycles | Stable x3 |
Reference Range
• Coproporphyrin (CP) I: 0−15 μg/L
• Coproporphyrin (CP) III: 0−49 μg/L
• Heptacarboxylporphyrins (7-CP): 0−2 μg/L
• Hexacarboxylporphyrins (6-CP): 0−1 μg/L
• Pentacarboxylporphyrins (5-CP): 0−2 μg/L
• Uroporphyrins (UP): 0−20 μg/L
Storage Instructions
Refrigerate and protect from light.
Causes for Rejection
Stored specimen not refrigerated; specimen exposed to light; acid preservative; pH <3
Footnotes
LOINC® Map
| Order Code | Order Code Name | Order Loinc | Result Code | Result Code Name | UofM | Result LOINC |
|---|---|---|---|---|---|---|
| 120980 | Porphyrins, Qn, Random U | 120988 | Uroporphyrins (UP) | ug/L | 11228-4 | |
| 120980 | Porphyrins, Qn, Random U | 120989 | Heptacarboxyl (7-CP) | ug/L | 2407-5 | |
| 120980 | Porphyrins, Qn, Random U | 120990 | Hexacarboxyl (6-CP) | ug/L | 27400-1 | |
| 120980 | Porphyrins, Qn, Random U | 120991 | Pentacarboxyl (5-CP) | ug/L | 11221-9 | |
| 120980 | Porphyrins, Qn, Random U | 120992 | Coproporphyrin (CP) I | ug/L | 9343-5 | |
| 120980 | Porphyrins, Qn, Random U | 120993 | Coproporphyrin (CP) III | ug/L | 9345-0 | |
| Order Code | 120980 | |||||
| Order Code Name | Porphyrins, Qn, Random U | |||||
| Order Loinc | ||||||
| Result Code | 120988 | |||||
| Result Code Name | Uroporphyrins (UP) | |||||
| UofM | ug/L | |||||
| Result LOINC | 11228-4 | |||||
| Order Code | 120980 | |||||
| Order Code Name | Porphyrins, Qn, Random U | |||||
| Order Loinc | ||||||
| Result Code | 120989 | |||||
| Result Code Name | Heptacarboxyl (7-CP) | |||||
| UofM | ug/L | |||||
| Result LOINC | 2407-5 | |||||
| Order Code | 120980 | |||||
| Order Code Name | Porphyrins, Qn, Random U | |||||
| Order Loinc | ||||||
| Result Code | 120990 | |||||
| Result Code Name | Hexacarboxyl (6-CP) | |||||
| UofM | ug/L | |||||
| Result LOINC | 27400-1 | |||||
| Order Code | 120980 | |||||
| Order Code Name | Porphyrins, Qn, Random U | |||||
| Order Loinc | ||||||
| Result Code | 120991 | |||||
| Result Code Name | Pentacarboxyl (5-CP) | |||||
| UofM | ug/L | |||||
| Result LOINC | 11221-9 | |||||
| Order Code | 120980 | |||||
| Order Code Name | Porphyrins, Qn, Random U | |||||
| Order Loinc | ||||||
| Result Code | 120992 | |||||
| Result Code Name | Coproporphyrin (CP) I | |||||
| UofM | ug/L | |||||
| Result LOINC | 9343-5 | |||||
| Order Code | 120980 | |||||
| Order Code Name | Porphyrins, Qn, Random U | |||||
| Order Loinc | ||||||
| Result Code | 120993 | |||||
| Result Code Name | Coproporphyrin (CP) III | |||||
| UofM | ug/L | |||||
| Result LOINC | 9345-0 |