Diseases Studied
The Rare Diseases Clinical Research Network is an NIH-funded research network of 21 active consortia or research groups working to advance treatment for diseases that are rare. Use the search tools on this page to find the diseases we currently study. You can reach out to the indicated consortia or research groups for more information on those diseases and studies underway.
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All Diseases > Acute intermittent porphyria
Acute intermittent porphyria (AIP)
Disease Category: Porphyrias
A rare, inherited, metabolic disorder characterized by partial deficiency of the enzyme hydroxymethylbilane synthase, which allows for build-up of porphyrin precursors throughout the body. Porphyrins are substances that bind metals to form complexes, such as the iron found in red blood cells. Symptoms include severe abdominal pain, constipation, rapid heartbeat, high blood pressure, seizures, behavioral changes, and peripheral neuropathy (sensory changes and profound muscle weakness in the extremities). Symptoms occur following triggers such as infections, hormonal changes, drug and alcohol abuse, and dietary changes.