Diagnosis; Screening

Establish or confirm diagnosis

Evaluation of patients who present with signs or symptoms suggestive of porphyria cutanea tarda, hereditary coproporphyria, variegate porphyria, congenital erythropoietic porphyria, erythropoietic protoporphyria, or X-linked dominant protoporphyria.

Is research allowed on the sample after clinical testing is complete? Help
N/A

The porphyrins are separated according to numbers of carboxyl units and isomer status. Analytic specificity is based on the combination of chromatographic behavior and the uniqueness of the porphyrins among substances in human specimens in terms of fluorescence spectra. Components quantified are 10 specific porphyrins of isomer series I and … The porphyrins are separated according to numbers of carboxyl units and isomer status. Analytic specificity is based on the combination of chromatographic behavior and the uniqueness of the porphyrins among substances in human specimens in terms of fluorescence spectra. Components quantified are 10 specific porphyrins of isomer series I and III, 4 groups of "isoporphyrins" (isomers other than of series I and III), and protoporphyrin.(Unpublished Mayo method) View more

Tests performed
Entire test performed in-house

Recovery was used to assess accuracy; mean recovery was 100%. Intra assay precision was performed at 5 levels: CV results ranged from 0% to 21.07% (N=5 each). Inter assay precision was performed at 5 levels: CV results ranged from 1.88% to 28.29%(N=5 each). The analytical measurement range is analyte dependent … Recovery was used to assess accuracy; mean recovery was 100%. Intra assay precision was performed at 5 levels: CV results ranged from 0% to 21.07% (N=5 each). Inter assay precision was performed at 5 levels: CV results ranged from 1.88% to 28.29%(N=5 each). The analytical measurement range is analyte dependent and ranges from 0- 3000.0 ug/dL. View more

Heme from red meat can contribute to fecal protoporphyrin concentrations and cause a misleading indication of erythropoietic protoporphyria, X-linked dominant protoporphyria, or variegate porphyria. Aspirin ingestion may cause minimal gastrointestinal bleeding, leading to false elevations of protoporphyrin. Specimen submitted should contain at least 100 g of feces. Specimens smaller than … Heme from red meat can contribute to fecal protoporphyrin concentrations and cause a misleading indication of erythropoietic protoporphyria, X-linked dominant protoporphyria, or variegate porphyria. Aspirin ingestion may cause minimal gastrointestinal bleeding, leading to false elevations of protoporphyrin. Specimen submitted should contain at least 100 g of feces. Specimens smaller than 100 g may not provide interpretable results. Specimens weighing less than 10 grams will be rejected. View more

Is proficiency testing performed for this test? Help
Yes

Method used for proficiency testing: Help
Formal PT program

PT Provider: Help
IPNET, RCPA

Description of PT method: Help
Formal PT program.

Description of internal test validation method: Help
This test was laboratory developed, and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements.

Software used to interpret novel variations Help
N/A

Laboratory's policy on reporting novel variations Help
N/A