Erythrocyte Porphyrin (EP), Whole Blood
Ordering Recommendation
Screen for erythropoietic protoporphyria (EPP) in patients with cutaneous photosensitivity.
New York DOH Approval Status
Specimen Required
Royal blue (EDTA), lavender (EDTA), pink (K2EDTA), or Tan ( K2EDTA). Use royal blue tube when also testing for lead.
Protect from light during collection, storage, and shipment. Transfer 1 mL whole blood to an ARUP Amber Transport Tube. (Min: 0.5 mL)
Refrigerated.
Specimens not collected in EDTA. Clotted specimens.
Specimen should be tested for lead FIRST to avoid potential contamination problems. Specimens not protected from light acceptable with a disclaimer.
Ambient: Unacceptable; Refrigerated: 2 weeks; Frozen: 1 month
Methodology
Fluorometry
Performed
Mon, Wed, Sat
Reported
1-4 days
Reference Interval
0-35 µg/dL
Interpretive Data
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)
Note
Elevated EP results are seen in early and late iron deficiency, in the anemia of chronic disease, and in chronic lead poisoning (typically when blood lead is greater than 25 µg/dL). Elevated protoporphyrin (as in erythropoietic protoporphyria) and zinc coproporphyrin (usually associated with childbirth) can increase the apparent EP signal. A more specific test for free protoporphyrin is Porphyrins, Serum Total (0080429). Specimens which are hemolyzed, clotted, or improperly aliquoted may show false elevations.
Hotline History
CPT Codes
84202
Components
Component Test Code* | Component Chart Name | LOINC |
---|---|---|
0020607 | Erythrocyte Porphyrin (EP) | 2898-5 |
Aliases
- FEP
- Free Erythrocyte Porphyrin
- Porphyrins (FEP)
- Protoporphyrin, Free Erythrocyte (FEP)
- Protoporphyrins, Total, Erythrocytes
- RBC Porphyrins
- Red Blood Cell Porphyrins