Abstract. Two clinical cases of acute porphyria are presented. Acute porphyria is a rare disease, a pathology associated with hereditary or acquired abnormalities of the biosynthesis of heme. The main features that distinguish these nosological forms are: the prevalence of precursors of porphyrins among laboratory-defined metabolites, rapid clinical progression of the disease; the absence of a correct diagnosis or late diagnosis result in life threateningneurological disorders. The main diagnostic difficulties are related to a non-specific character of clinical signs of acute intermittent porphyria, the clinical signsimitate a large range of somatic, including emergency, conditions. Despite the fact that porphyria belongs to orphan diseases, the polymorphism of the clinical picture, the difficulty of obtaining pathogenetic drugs in medical institutions for the treatment of this disease in Russia, familiarization with its clinical features is useful for a wide range of specialists.

Keywords: acute porphyria, difficulty of diagnosis, heme arginate