Ordering Recommendation

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

Mnemonic
FEP
Methodology

Fluorometry

Performed

Mon, Wed, Sat

Reported

1-4 days

New York DOH Approval Status
This test is New York DOH approved.
Specimen Required
Patient Preparation
Collect

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

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



Compliance Category

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
N/A
CPT Codes

84202

Components
Component Test Code* Component Chart Name LOINC
0020607 Erythrocyte 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
Erythrocyte Porphyrin (EP), Whole Blood