Porphyria: Difference between revisions

Deficiency in the enzymes of the porphyrin pathway leads to insufficient production of heme. Heme metabolism plays a central role in cellular metabolism. This is, however, not the main problem; most enzymes — even when less functional — have enough residual activity to assist in heme biosynthesis. The principal problem in these deficiencies is the accumulation of porphyrins, the heme precursors, which are toxic to tissue in high concentrations. The chemical properties of these intermediates determine in which tissue they accumulate, whether they are [[photosensitive]], and how the compound is excreted (in the [[urine]] or [[feces]]).