Selected methods have been described for detecting an increase of porphyrins in the urine, stool, and blood. These methods are rapid and are particularly useful for use in outpatients or office practice to evaluate patients with sunlight sensitivity in whom porphyria is suspected. Also included are photomicrographs of fluorescing erythrocytes and a table giving examples of quantitative porphyrin values in stools, erythrocytes and urine that may be observed in different types of porphyria.
Cripps DJ, Peters HA. Fluorescing Erythrocytes and Porphyrin Screening Tests on Urine, Stool, and BloodInvestigation of Photosensitivity. Arch Dermatol. 1967;96(6):712-720. doi:10.1001/archderm.1967.01610060106022