Laboratory Test Information Guide

Details for Porphyrin Screen and Quantitation, Feces

Test Name: Porphyrin Screen and Quantitation, Feces
Alternate Name(s): Uroporphyrin III
Heptacarboxylic acid
Hexacarboxylic acid
Pentacarboxylic acid
Coproporphyrin I
Coproporphyrin III
Laboratory: Core (VH)
Specimen Type: Feces (Random)
Collection Information: Collect a minimum of 50 g of feces in a sterile container. Collect in a dark container or wrap with foil to protect specimen from light. If wrapped with foil, specimen must be labelled inside and outside of the light-protecting wrap.
Test Schedule: Referred out Monday-Thursday
Turnaround time from when specimen
is received in testing laboratory:
10 days
Reference Range: Screen: Normal

Uroporphyrin III: ≤1.0 nmol/g
Heptacarboxylic acid: ≤1.0 nmol/g
Hexacarboxylic acid: ≤1.0 nmol/g
Pentacarboxylic acid: ≤1.0 nmol/g
Coproporphyrin I: ≤13.0 nmol/g
Coproporphyrin III: ≤12.0 nmol/g
Copro III/Copro I ratio: ≤1.6
Protoporphyrin: ≤38.0 nmol/g

All results are reported as nmol/g dry weight.

Interpretation provided on report.

Reference intervals are for adults only and are not available for individuals 17 years of age or younger.
Effective Date: 2012-12-10
Revised Date: 2021-07-05
Critical Value:  
Interpretive Comments:  
Special Processing:  
Comments: Screen will be performed first. Quantitation will automatically be performed (and billed) if preliminary screen is positive.
Method of Analysis: Spectrophotometry and HPLC
Critical Information Required:  
Storage & Shipment: Store and ship frozen and protected from light.
System Codes: 
Referred To: In-Common Laboratories

Questions? Comments? Contact Laura Gopaul