Acute intermittent porphyria (AIP), also called Swedish porphyria, is a rare inborn error of metabolism (IEM) and autosomal dominant disorder of heme biosynthesis caused by a defective HMBS gene. The HMBS gene codes for the protein hydroxymethylbilane synthase (porphobilinogen deaminase) which catalyzes the synthesis of porphobilinogen into hydroxymethylbilane. This disorder is characterized by a large accumulation of 5-aminolevulinic acid or porphobilinogen in both urine and serum. Most patients are asymptomatic between attacks. Symptoms of the disorder include abdominal pain, constipation, vomiting, hypertension, muscle weakness, seizures, delirium, coma, and depression. Treatment involves undertaking a high-carbohydrate diet and, during severe attacks, a glucose 10% infusion. It is estimated that AIP affects 5.9 per 1 000 000 people.

Acute Intermittent Porphyria References

Porphyrin Metabolism References