A prevalência de porfiria no Brasil e o perfil dos portadores dessa doença

Abstract

Porphyrias are rare diseases, mainly hereditary (autosomal dominant), but that in some circumstances, the metabolic alteration responsible for the disorder can also be acquired. Classically, they occur due to specific enzyme deficiencies in the biosynthesis pathway of the heme group by erythroblasts, bone marrow or liver cells. The deficiency of enzymes mediating the biosynthesis of the heme group can lead to overproduction and accumulation of metabolic precursors. The precursor that is accumulated and the place where it is accumulated give rise to the different types of porphyria. The objective of this study was to analyze the data of registries of an association of porphyria carriers based in Brazil to evaluate prevalence in the country and to trace the profile of porphyria carriers registered in this association. Data from 535 porphyria carriers whose association registration have occurred between April 2006 and August 2018 were analyzed. A retrospective and descriptive study was performed based on the cadastral data submitted to the simple descriptive statistical analysis, with the results presented in the form of graphs. The results based on these data showed that the prevalence of porphyria among the Brazilian population was 2.5 cases per million. There are cases registered in all regions of the country, with the Distrito Federal having the highest prevalence. For the analysis by region, the south and southeast regions are the ones with the highest prevalence. Acute intermittent porphyria was the most prevalent porphyria among registries with about 63% records, followed by porphyria cutanea tarda with approximately 19% of the cases. Porphyria ALA dehydratase was the least prevalent with only 1 case registered. Women are more affected by porphyrias than men, accounting for 77% of the registrations. There are porphyria cases in all age ranges, but most of the records are from people who are currently age between 30 and 40 years old. It was observed that although porphyrias are considered rare diseases, a considerable number of people are affected by them in Brazil, and that prevalence values are still underestimated.