Mayo Test Catalog, (Sorted By Test Name) - Mayo Medical ...

PEE
defect in the biosynthesis of heme. However, the specific type of porphyria cannot be determined by total
porphyrin analysis alone. Total RBC porphyrin values >80 mcg/dL suggest the existence of an
intoxication problem or a metabolic problem that involves accelerated erythropoiesis. If the total RBC
porphyrin concentration is elevated, additional testing (fractionation assays) is required to identify and
quantify the specific affected porphyrin. Increased total RBC porphyrin concentrations may be due to:
-Free protoporphyrin, the predominant form that is elevated in patients with erythropoietic protoporphyria
(EPP) -Zinc protoporphyrin, elevated in patients with heavy metal intoxication or iron deficiency anemia
-Uroporphyrin and coproporphyrin, preferentially elevated in patients with congenital erythropoietic
porphyria (CEP) A written interpretation is included with all reports. When abnormal results are detected,
a detailed interpretation is given, including: -An overview of the results and their significance -Elements
of a differential diagnosis -Recommendations for additional biochemical testing A normal RBC porphyrin
evaluation does not rule out other forms of porphyria including porphyria cutanea tarda (PCT), acute
intermittent porphyria (AIP), hereditary coproporphyria (HCP), and variegate porphyria (VP). See The
Heme Biosynthetic Pathway in Special Instructions.
Reference Values:
PORPHYRINS, TOTAL, RBC