Evaluate cutaneous photosensitivity to exclude or include porphyria cutanea tarda (PCT).
Quantitative High Performance Liquid Chromatography
24-hour or random urine. Refrigerate 24-hour specimens during collection.
Protect from light. Transfer 4 mL aliquot of urine to an ARUP Amber Transport Tube. (Min: 2 mL) Record total volume and collection time interval on transport tube and test request form.
Body fluids other than urine.
Ambient: Unacceptable; Refrigerated: 4 days; Frozen: 1 month
|Uroporphyrin||0-4 µmol/mol crt|
|Heptacarboxylate Porphyrin||0-2 µmol/mol crt|
|Coproporphyrin I||0-6 µmol/mol crt|
|Coproporphyrin III||0-14 µmol/mol crt|
|0020473||Creatinine, Urine - per 24h||
Results are normalized to creatinine concentration and reported as a ratio of amounts (micromoles of porphyrin/moles of creatinine).
Per 24h calculations are provided to aid interpretation for collections with a duration of 24 hours and an average daily urine volume. For specimens with notable deviations in collection time or volume, ratios of analytes to a corresponding urine creatinine concentration may assist in result interpretation.
This test was developed and its performance characteristics determined by ARUP Laboratories. It has not been cleared or approved by the US Food and Drug Administration. This test was performed in a CLIA certified laboratory and is intended for clinical purposes.
Laboratory Developed Test (LDT)
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), Urine (ARUP test code 0080260).
|Component Test Code*||Component Chart Name||LOINC|
|0020207||Creatinine, Urine - per volume||2161-8|
|0020208||Creatinine, Urine - per 24h||2162-6|
|0080365||Uroporphyrin - ratio to CRT||32043-2|
|0080366||Heptacarboxylate - ratio to CRT||38175-6|
|0080459||Porphyrin Urine Interpretation||49292-6|
|2002059||Coproporphyrin I - ratio to CRT||45313-4|
|2002061||Coproporphyrin III - ratio to CRT||45315-9|
- Heptacarboxyl Porphyrin
- Hexacarboxyl Porphyrin
- Pentacarboxyl Porphyrin
- Porphyria Cutanea Tarda (PCT)
- Porphyrins, Fractionated, Quantitative, 24-Hour