Preferred test for the confirmation of a diagnosis of porphyria cutanea tarda type II and hepatoerythropoietic porphyria.
Patient should abstain from alcohol for 24 hours.
Abstinence is essential for at least 24 hours as alcohol suppresses enzyme activity for 24 hours after ingestion.
Dk green Sodium heparin (Na hep), no gel
Lavender (EDTA), 4mL
Dk green Lithium heparin (Li hep), no gel
Refrigerated (preferred) – 14 days
Ambient – 7 days
Frozen – NO
High-Performance Liquid Chromatography (HPLC)/Incubation of lysed erythrocytes
≥1.0 Relative units (RU) - normal
0.80 - 0.99 Relative units (RU) - indeterminate
<0.80 Relative units (RU) - indicative of PCT type II