Acute porphyrias (AP) are a group of metabolic disorders resulting from deficiency of four different enzymes of the heme biosynthetic pathway (Fig. 1) [1,2]. Carriers of these enzymatic defects are at a risk of presenting acute and severe neuro-visceral attacks (acute porphyric attacks, APAs) that are associated with induction of liver 5-aminolevulinate synthase (ALAS1), responsible for overproduction and tissue accumulation of neurotoxic non-porphyrin intermediates [porphobilinogen (PBG) and δ-aminolevulinic acid (ALA)] [1-5].
