Porphobilinogen and Aminolevulinic Acid, Plasma

Use

This test is useful as an equivalent to urine for the first-line evaluation of suspected acute porphyria, particularly when a urine specimen cannot be obtained during a symptomatic episode. It is also used to monitor patients undergoing treatment for acute intermittent porphyria or other acute porphyrias. Plasma porphobilinogen and aminolevulinic acid levels are elevated during the symptomatic phase of acute porphyrias such as acute intermittent porphyria, hereditary coproporphyria, and variegate porphyria. Isolated elevation of aminolevulinic acid may indicate ALA dehydratase deficiency porphyria or secondary inhibition of ALA dehydratase.