[Urinary excretion of porphyrins and their precursors. Longterm observations in acute intermittent porphyrias (author's transl)].

On the basis of many years of examination and supervision of 26 patients with acute intermittent porphyria three different types of excretion behavior in the urine can be distinguished. 1. After porphyric crises the urinary porphyrin content is completely normalized. 2. Even after the crisis the excretion levels for porphyrins remain very high. 3. The urinary porphyrins return to normal levels but the increases in precursors such as delta-aminolevulinic acid and porphobilinogen still persist. 4. In the diagnosis true acute coproporphyria and increased of excretion of precursors must be differentiated as well as increased coproporphyrin resulting from liver diseases, exogenic, toxic influences and secondary disorders of porphyrin metabolism.