[Porphyrin fluorescence in plasma of various types of porphyria].

Fluorescence spectra of plasma porphyrin were measured in 6 patients with the acute intermittent porphyria (AIP), 30 patients with variegate porphyria (PV), 2 patients with hereditary coproporphyria, 2 patients with porphyria cutanea tarda, and in 6 patients with erythropoietic protoporphyria (EPP). It was found that the excitation and emission wavelengths at which maximum fluorescence is seen may help to diagnose and differentiate PV and EPP. In patients with AIP spectrum characteristic for porphyria of such a type was noted in all patients during the attack of disease and in only 33% of patients in remission. Fluorescence spectrum was normal in asymptomatic family members. In variegate porphyria spectrum with a characteristic maximum of fluorescence was noted in all patients during an attack and remission, and 62% of the asymptomatic family members.