Lipoprotein abnormalities in patients with asymptomatic acute porphyria

Acute intermittent porphyria: focus on possible mechanisms of acute and chronic manifestations

Porphyrias are a group of inherited metabolic diseases that include eight types, each of which is caused by a mutation that affects an enzyme of the heme biosynthetic pathway. When an enzyme defect has physiological significance, it leads to overproduction of pathway precursors prior to the defective step. The partial absence of the third enzyme in the heme biosynthetic pathway, porphobilinogen deaminase (PBGD) also known as hydroxymethylbilane synthase (HMBS), results in acute intermittent porphyria (AIP), which affects mainly women. Subjects who had AIP symptoms were deemed to have manifest AIP (MAIP). Clinical manifestations are usually diverse and non-specific. Acute AIP episodes may present with abdominal pain, nausea, and vomiting, and repeated episodes may result in a series of chronic injuries. Therefore, studying the mechanisms of acute and chronic manifestations of AIP is of great significance. This review aims to summarize the possible mechanisms of acute and chronic manifestations in patients with AIP.

Nutrients and Porphyria: An Intriguing Crosstalk

Porphyria refers to a group of fascinating diseases from a metabolic and nutritional standpoint as it provides an example of how metabolic manipulation can be used for therapeutic purposes. It is characterized by defects in heme synthesis, particularly in the erythrocytes and liver. Specific enzymes involved in heme biosynthesis directly depend on adequate levels of vitamins and minerals in the tissues. Moreover, micronutrients that are required for producing succinyl CoA and other intermediates in the Krebs (TCA) cycle are indirectly necessary for heme metabolism. This review summarizes articles that describe the nutritional status, supplements intake, and dietary practices of patients affected by porphyria, paying special attention to the therapeutic use of nutrients that may help or hinder this group of diseases.

Assessing nutritional status of acute intermittent porphyria patients

BACKGROUND

Acute intermittent porphyria (AIP) is a metabolic disease of haem synthesis, whose haem precursors may accumulate in the body. A well-balanced diet may prevent the symptoms, so that porphyric patients should be monitored closely during therapy for possible complications concerning any progression of acute porphyria. The aim was to evaluate the nutritional status of patients with AIP and to assess their compliance with nutritional recommendations, comparing the findings with a control group and assessing any possible nutritional deficiency.

MATERIAL AND METHODS

Sixteen patients with AIP and a control group were evaluated by means of a lifestyle questionnaire, the Nutrition Screening Initiative checklist and a dietary questionnaire. The following diet quality indicators were calculated: animal and vegetal proteins, protein quality index, PUFA/SFA and MUFA + PUFA/SFA ratios, insoluble dietary fibre (DF)/total DF, soluble DF/total DF and insoluble DF/soluble DF ratios, thiamine, riboflavin and niacin density and the vitamin B6/protein ratio.

STATISTICAL METHODS

Differences in continuous variables were compared using the unpaired Student's t-test and the chi-square test for nonparametric variables. The odds ratio (OR) of malnutrition was also used.

RESULTS

Our patients showed a low intake of carbohydrates, a high lipid intake and very high protein intake, and accompanied by an inadequate intake of zinc, folic acid and tocopherol, increasing the risk of malnutrition for energy, Ca, Fe, Mg, K, folic acid and tocopherols.

CONCLUSIONS

The patients with AIP studied individually show an increased risk of malnutrition and, given the potential increase of oxidative stress in patients with porphyria, it is recommended that they should increase their intake of carbohydrates, minerals and antioxidant nutrients.

Nutritional Assessment of Patients Affected by Porphyria Variegata

AIMS

To describe the nutritional status and dietary practices of patients affected by porphyria variegata, paying special attention to the consumption of nutrients that may help or hinder the condition, and to assess the compliance with prevalent nutritional recommendations.

METHODS

Cross-sectional study. 24 individuals affected by porphyria variegata (16 females and 8 males; mean age 46.8 (SD 19.5) years) from the Balearic Islands (Spain) recruited through the Balearic Porphyria Association. Dietary questionnaires (7-day dietary record and a semi-quantitative food frequency questionnaire), socio-demographic, lifestyle and health status interviews and anthropometric measurements were carried out.

RESULTS

According to current recommendations for the Spanish population and to specific recommendations for porphyria patients, the daily intake of saturated fat (13.2% of total energy), sugars (16.9% of total E), cholesterol (387 mg) and alcoholic beverages (1.1 servings per day) were too high whereas the consumption of total carbohydrates (43.5% of total E), vitamin E (69.5% of RDI), beta-carotene (63.1% of RDI) and vitamin D (42.4% of RDI) was lower than recommended.

CONCLUSIONS

Dietary pattern observed among porphyria variegata patients was in line with current dietary trends in the Balearic Islands. Nutritional recommendations to these individuals for the management of porphyria are poorly met. It is necessary to translate these recommendations into food-based dietary guidelines based on prevailing dietary patterns.