GTR Home > Conditions/Phenotypes > Acute intermittent porphyria

Summary

Excerpted from the GeneReview: Acute Intermittent Porphyria
Acute intermittent porphyria (referred to as AIP in this GeneReview) results from half-normal activity of the enzyme hydroxymethylbilane synthase (HMBS). It is characterized clinically by life-threatening acute neurovisceral attacks of severe abdominal pain without peritoneal signs, often accompanied by nausea, vomiting, tachycardia, and hypertension. Attacks may be complicated by neurologic findings (mental changes, convulsions, and peripheral neuropathy that may progress to respiratory paralysis), and hyponatremia. Acute attacks, which may be provoked by certain drugs, alcoholic beverages, endocrine factors, calorie restriction, stress, and infections, usually resolve within two weeks. Most individuals with AIP have one or a few attacks; about 5% (mainly women) have recurrent attacks (defined as >4 attacks/year) that may persist for years. Other long-term complications are chronic renal failure, hepatocellular carcinoma (HCC), and hypertension. Attacks, which are very rare before puberty, are more common in women than men. All individuals with a genetic change in the gene HMBS that predisposes to AIP are at risk of developing acute attacks; however, most never have symptoms and are said to have latent (or presymptomatic) AIP.

Available tests

35 tests are in the database for this condition.

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Genes See tests for all associated and related genes

  • Also known as: PBG-D, PBGD, PORC, UPS, HMBS
    Summary: hydroxymethylbilane synthase

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