Porphyrins, Fractionated, Quantitative, 24-Hour Urine

Test Code
729

CPT Codes
84120

Includes
Coproporphyrin I, Coproporphyrin III, Heptacarboxyporphyrin, Hexacarboxyporphyrin, Pentacarboxyporphyrin, Total Porphyrins, Uroporphyrin I, Uroporphyrin III

Preferred Specimen
2 mL of a preserved 24-hour urine, submitted in a plastic, leak-proof container

Minimum Volume
1 mL

Other Acceptable Specimens
Unpreserved 24-hour urine, submitted in a plastic, leak-proof container

Instructions
Protect sample from light: 2 mL 24-hour urine in 5 grams sodium carbonate (Na2CO3) container or no preservative container.

24-hour urine collected with 5 grams of sodium carbonate, refrigerated, and protected from light during collection is preferred. Collection with no preservative is acceptable, if properly refrigerated and light protected. 24-hour total volume must be provided on the test request form.

Transport Container
Plastic screw-cap vial - protected from light

Transport Temperature
Refrigerated (cold packs)

Specimen Stability
Room temperature: Unacceptable
Refrigerated: 7 days
Frozen: 30 days

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Received room temperature • Not protected from light • pH <4.0

Methodology
High Performance Liquid Chromatography (HPLC)

Setup Schedule
Set up: Tues-Sat p.m.; Report available: 2-6 days

Reference Range

Adult Reference Ranges
Uroporphyrin I	4.1-22.4 mcg/24 h
Uroporphyrin III	0.7-7.4 mcg/24 h
Heptacarboxyporphyrin	≤3.3 mcg/24 h
Hexacarboxyporphyrin	≤10 mcg/24 h
Pentacarboxyporphyrin	≤4.6 mcg/24 h
Coproporphyrin I	7.1-48.7 mcg/24 h
Coproporphyrin III	11.0-148.5 mcg/24 h
Total Porphyrins	35-210.7 mcg/24 h

Clinical Significance
Porphyria is a group of distinct disorders characterized by the abnormal accumulation of porphyrins or porphyrin precursors. Porphyrin Fractionation of Urine is useful in diagnosing porphyrin cutanea tarda, hereditary coproporphyria, and variegate porphyria.

Performing Laboratory
Quest Diagnostics Nichols Inst San Juan Capistrano
33608 Ortega Highway
San Juan Capistrano, CA 92675

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.