Porphyrins, Quantitative, Random Urine

Urine porphyrins are useful for the evaluation of cutaneous photosensitivity to exclude porphyria cutanea tarda (PCT). Evaluation of neurologic and/or psychiatric symptoms associated with acute porphyrias, such as acute intermittent porphyria (AIP), requires urine porphobilinogen (PBG) testing. Refer to Porphobilinogen (PBG), Quantitative, Random Urine [003053].

For initial evaluation of porphyrias. Use Porphyrins, Quantitative, 24-Hour Urine [003194] to follow up random urine abnormal results.

Excess urinary porphyrin excretion, or porphyrinuria, results from inhibition of key enzymatic steps in such clinical conditions as genetic deficiencies in heme production enzymes, hepatitis, renal disease, and erythroid disease, as well as by heavy metal inhibition of heme enzyme synthesis.¹ Both in experimental animals and in humans exposed to heavy metals, elevated levels of porphyrins have been found in urine.¹

1. Woods JS. Altered porphyrin metabolism as a biomarker of mercury exposure and toxicity. Can J Physiol Pharmacol. 1996 Feb; 74(2):210-215. PubMed 8723034