Erythrocyte Porphyrin (EP), Whole Blood
0020610
Ordering Recommendation
Screen for erythropoietic protoporphyria (EPP) in patients with cutaneous photosensitivity and blisters.
Mnemonic
FEP
Methodology
Fluorometry
Performed
Mon, Wed, Sat
Reported
1-4 days  
New York DOH Approval Status
This test is New York DOH approved.
Submit With Order
Specimen Required
Patient Preparation
  
Collect
Royal blue (EDTA), lavender (EDTA), or pink (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
Refrigerated.  
Unacceptable Conditions
Specimens not collected in EDTA. Clotted specimens.  
Remarks
Specimen should be tested for lead FIRST to avoid potential contamination problems. Specimens not protected from light acceptable with a disclaimer.  
Stability
Ambient: Unacceptable; Refrigerated: 2 weeks; Frozen: 1 month  
Reference Interval
0-35 µg/dL  
Interpretive Data
 
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.
CPT Code(s)
84202
Components
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 click the sidebar link to access the Interface Map.
Aliases
  • FEP
  • Free Erythrocyte Porphyrin
  • Porphyrins (FEP)
  • Protoporphyrin, Free Erythrocyte (FEP)
  • Protoporphyrins, Total, Erythrocytes
  • RBC Porphyrins
  • Red Blood Cell Porphyrins