Porphyria

Mary, living with acute hepatic porphyria

Porphyria

Understanding Porphyria

Porphyria is a family of rare, genetic diseases characterized by potentially life-threatening attacks and, for some patients, chronic debilitating symptoms that negatively impact daily functioning and quality of life. Porphyria includes eight subtypes, and each has unique manifestations, making an accurate diagnosis even more challenging. Four of these subtypes, a family of diseases referred to as acute hepatic porphyria (AHP), result from a genetic defect leading to deficiency in one of the enzymes of the heme biosynthesis pathway in the liver: acute intermittent porphyria (AIP), variegate porphyria (VP), hereditary coproporphyria (HCP), and ALAD-deficiency porphyria (ADP).

In the United States and Europe, approximately 5,000 people experience one or more attacks annually, and approximately 1,000 people suffer frequent and severe attacks. Common treatment approaches for AHP include carbohydrate loading, intravenous (IV) glucose, and IV hemin, which can be administered during an attack or sometimes between attacks (prophylactically). However, hemin is not currently approved for the prophylactic treatment of AHP. Currently, there are no treatments approved to prevent debilitating attacks and treat the chronic symptoms of AHP.

Common symptoms significantly impact quality of life:

Affected individuals often experience some combination of the following symptoms:

Autonomic Nervous System Injury
  • Severe, diffuse abdominal pain
  • Nausea and/or vomiting
  • Dark/reddish urine (does not manifest in all porphyria patients)
Peripheral Nervous System Neuropathy
  • Weakness
  • Numbness
  • Respiratory failure
Central Nervous System Neuropathy
  • Confusion
  • Anxiety
  • Seizures
  • Hallucinations
  • Fatigue
Cutaneous Findings (HCP and VP only)
  • Lesions on sun-exposed skin; chronic/blistering

Affected individuals often experience some combination of the following symptoms:

Autonomic Nervous System Injury
  • Severe, diffuse abdominal pain
  • Nausea and/or vomiting
  • Dark/reddish urine (does not manifest in all porphyria patients)
Peripheral Nervous System Neuropathy
  • Weakness
  • Numbness
  • Respiratory failure
Central Nervous System Neuropathy
  • Confusion
  • Anxiety
  • Seizures
  • Hallucinations
  • Fatigue
Cutaneous Findings (HCP and VP only)
  • Lesions on sun-exposed skin; chronic/blistering

Affected individuals often experience some combination of the following symptoms:

Autonomic Nervous System Injury
  • Severe, diffuse abdominal pain
  • Nausea and/or vomiting
  • Dark/reddish urine (does not manifest in all porphyria patients)
Peripheral Nervous System Neuropathy
  • Weakness
  • Numbness
  • Respiratory failure
Central Nervous System Neuropathy
  • Confusion
  • Anxiety
  • Seizures
  • Hallucinations
  • Fatigue
Cutaneous Findings (HCP and VP only)
  • Lesions on sun-exposed skin; chronic/blistering

What causes acute hepatic porphyria?

What causes acute hepatic porphyria?

What causes acute hepatic porphyria?

What Is it Like to Live with and Care for a Person with Porphyria?

Mary: Living with
Acute Intermittent Porphyria

Candace and Anne: Living & Caregiving
with Porphyria

Caregiving Perspectives:
Anna & Candace, Porphyria

CLINICAL TRIALS

Interested in learning about our porphyria studies? Get started here.

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PINPOINT AHP

Pinpoint AHPTM provides patients and their caregivers a variety of resources to help them understand the types of acute hepatic porphyria (AHP) and recognize the signs and symptoms.
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ALNYLAM ACT

Alnylam Act provides no-charge, independent genetic testing and counseling to individuals in the US and Canada who may have porphyria.

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SCIENCE OF RNAi

RNA interference marks a revolution in biology built on Nobel Prize-winning research.

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References

  1. Balwani M, Desnick RJ. The porphyrias: advances in diagnosis and treatment. Blood. 2012;120(23):4496-4504.
  2. Anderson KE, Bloomer JR, Bonkovsky HL, et al. Recommendations for the diagnosis and treatment of the acute porphyrias. Ann Intern Med. 2005;142(6):439-450.
  3. Bissell DM, Wang B. Acute hepatic porphyria. J Clin Transl Hepatol. 2015;3(1):17-26.
  4. Bonkovsky HL. Neurovisceral porphyrias: what a hematologist needs to know. Hematology Am Soc Hematol Educ Program. 2005:24-30.
  5. American Porphyria Foundation. Acute Intermittent Porphyria (AIP). http://www.porphyriafoundation.com/about-porphyria/types-of-porphyria/AIP.
  6. EPNET—The Porphyria Consortium. http://porphyria.eu/en/content/introduction-porphyria
  7. Puy H, Gouya L, Deybach JC. Porphyrias. Lancet 2010;375:924-937.

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