Erythrocyte Porphyrin (EP), Whole Blood
Ordering Recommendation

Screen for erythropoietic protoporphyria (EPP) in patients with cutaneous photosensitivity.

Mon, Wed, Sat
1-4 days
New York DOH Approval Status
This test is New York DOH approved.
Submit With Order
ARUP Consult®
Disease Topics
Specimen Required
Patient Preparation
Royal blue (EDTA), lavender (EDTA), pink (K2EDTA), or Tan ( K2EDTA). Use royal blue tube when also testing for lead.  
Specimen Preparation
Protect from light during collection, storage, and shipment. Transfer 1 mL whole blood to an ARUP Amber Transport Tube. (Min: 0.5 mL) 
Storage/Transport Temperature
Unacceptable Conditions
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 
Reference Interval
0-35 µg/dL
Interpretive Data

Statement B: Compliance Statement B: For laboratory developed tests not using a RUO kit, and for FDA approved, cleared or 510(k) exempt assays with alterations. This test was developed and its performance characteristics determined by ARUP Laboratories. The U. S. Food and Drug Administration has not approved or cleared this test; however, FDA clearance or approval is not currently required for clinical use. The results are not intended to be used as the sole means for clinical diagnosis or patient management decisions.

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
Component Test Code*Component Chart NameLOINC
0020607Erythrocyte Porphyrin (EP)2898-5
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please view this test within the Laboratory Test Directory found at
  • FEP
  • Free Erythrocyte Porphyrin
  • Porphyrins (FEP)
  • Protoporphyrin, Free Erythrocyte (FEP)
  • Protoporphyrins, Total, Erythrocytes
  • RBC Porphyrins
  • Red Blood Cell Porphyrins