Todays Highlight What is HCP? Hereditary coproporphyria

  • Jun 29, 2020

Hereditary coproporphyria

Do you have HCP and would like to share your story the APF is collecting personal journeys with HCP.  Please feel free to contact to submit your story and bring awareness to the Porphyria community.


Other Names:

Coproporphyria; Coproporphyria hereditary; Hereditary coproporphyria porphyria; See More


Congenital and Genetic DiseasesKidney and Urinary DiseasesMetabolic disordersSee More

This disease is grouped under:




Hereditary coproporphyria (HCP) is a rare inherited form of liver (hepatic) porphyria, characterized by neurological symptoms in the form of episodes (acute attacks) of stomach pain, nausea, vomiting, weakness, numbness, and pain in the hands and feet (neuropathy).[1][2] The porphyrias are a group of blood conditions caused by a lack of an enzyme in the body that makes heme, an important molecule that carries oxygen throughout the body and is vital for all of the body’s organs.[1] Symptoms usually begin around 20-30 years of age, but have been reported at younger ages. Signs and symptoms present during the attacks may include body pain, nausea and vomiting, increased heart rate (tachycardia), and high blood pressure.[2]  Less common symptoms include seizures, skin lesions, and paralysis of the arms and legs, body trunk, and respiratory muscles. Most individuals with HCP do not have any signs or symptoms between attacks.[3] HCP is caused by mutations in the CPOX gene and is inherited in an autosomal dominant manner.[1268] Diagnosis is based on the symptoms and specific blood, urine and stool testing. Treatment is based on preventing the symptoms. An acute attack requires hospitalization, medications, and treatment with heme therapy.[4]  

Last updated: 9/4/2019



The symptoms of hereditary coproporphyria (HCP) may be different from person to person. Some people may be more severely affected than others and not everyone with hereditary coproporphyria will have the same symptoms. Many individuals with a CPOX gene mutation do not experience any symptoms of HCP.[3][5] 

In people with HCP, additional factors; such as hormonal changes, certain drugs, excess alcohol consumption, infections, and fasting or dietary changes; may trigger the appearance of symptoms. Symptoms appear as acute attacks or episodes that develop over a period of days. The timing and severity of attacks vary from one person to another.[1]

The symptoms of an acute attack include:[2]

• Severe stomach pain leading to nausea and vomiting
-back and leg pain
• High blood pressure
• Rapid heartbeat (tachycardia)
• Seizures (less common)
• Weakness, numbness in the arms and legs (peripheral neuropathy)
• Skin findings (in about 20% of people with HCP)
-extreme sensitivity to sunlight (photosensitivity)
-fragile skin

In between attacks, people with HCP are often symptom-free. 


Last updated: 4/9/2019

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

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Medical Terms Other Names

Learn More:


80%-99% of people have these symptoms
Abdominal pain

Pain in stomach

[ more  ]

Excessive, persistent worry and fear



[ more  ]





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Do you have more information about symptoms of this disease? We want to hear from you.

Last updated: 6/1/2020



Hereditary coproporphyria (HCP) is caused by a genetic change (mutation in the CPOX gene.  However, having a CPOX gene mutation alone does not cause symptoms. Additional factors (such as hormonal changes, specific drugs, excess alcohol, fasting) are needed to trigger an attack and the appearance of symptoms.  Some people with CPOX gene mutations never have symptoms of HCP.[2]

The American Porphyria Foundation offers a drug database with safety information about the interaction of specific drugs in patients with porphyria. 




Hereditary coproporphyria (HCP) is inherited in an autosomal dominant pattern.[1][2] All individuals inherit two copies of each gene. In autosomal dominant conditions, having a mutation in just one copy of the CPOX gene causes the person to have HCP. The mutation can be inherited from either parent. Some people are born with hereditary coproporphyria due to a new genetic mutation (de novo) and do not have a history of this condition in their family. There is nothing either parent can do, before or during pregnancy, to cause a child to have this.

Each child of an individual with an autosomal dominant condition has a 50% or 1 in 2 chance of inheriting the mutation and the condition. Offspring who inherit the mutation may develop HCP, although they could be more or less severely affected than their parent. Sometimes a person may have a CPOX gene mutation for HCP and show no signs or symptoms of it.  

Last updated: 4/9/2019



The diagnosis of hereditary coproporphyria (HCP) is suspected first based on the clinical signs and symptoms, usually during an acute attack.  Once a person is suspected of having HCP, examination of urine, blood, and stool (fecal) samples is typically done.  These lab tests are usually done at the time of the acute attack and look for elevated levels of compounds found to be associated with several different types of porphyria.[2][5]

To identify the specific type of porphyria an individual has, genetic testing can be performed to look for mutations in the CPOX gene.[2]    

At least one study suggesting diagnostic criteria for the acute dominantly inherited forms of porphyria has been published.[6]

Last updated: 4/9/2019

Testing Resources

  • The Genetic Testing Registry (GTR) provides information about the genetic tests for this condition. The intended audience for the GTR is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.



    There is no specific treatment for hereditary coproporphyria (HCP). Treatment is aimed at managing the symptoms of HCP that occur during an acute attack. Hospitalization is often necessary for acute attacks, and medications for pain, nausea and vomiting, and close observation are generally required. Some attacks may be managed by giving the person a large amount of glucose or other carbohydrates. More severe attacks are treated with heme therapy, given through a vein (intravenously). Panhematin® is currently the only commercially available heme therapy for treatment and prevention of acute porphyria attacks in the United States. Heme arginate, which is marketed in some other countries, is another type of heme therapy.[1][2][4]

    Attacks can also be avoided by avoiding the ‘trigger’ for the attack. The trigger can be different for different people. Triggers include certain medications, alcohol, dieting, and hormonal changes in the body. Sometimes, however, the trigger is unknown. If the person with HCP has skin symptoms, avoiding excess sun exposure can reduce the blisters and skin lesions.[4][5]

    Last updated: 4/9/2019

    Management Guidelines

    • Orphanet Emergency Guidelines is an article which is expert-authored and peer-reviewed that is intended to guide health care professionals in emergency situations involving this condition.  
    • The American Porphyria Foundation offers a document that includes information about porphyria, types, testing, and treatment with Panhematin®.  Click the "document" link above to view these guidelines.



      The long term outlook for people with hereditary coproporphyria (HCP) varies with the severity of the symptoms. With early diagnosis and treatment, hereditary coproporphyria is rarely life-threatening.  Some people with HCP may have long-term pain and may be at increased risk for liver and kidney disease.[2][4]

      Last updated: 4/9/2019



      Hereditary coproporphyria (HCP) is rare. The exact incidence is unknown.  One study suggested that about 1/5,000,000 people have HCP in Europe.[7] Females are more commonly affected than males. Because this condition is often misdiagnosed and many people who have CPOX mutations do not have symptoms, the incidence of this condition may be higher.  

      Last updated: 4/9/2019

      Do you have updated information on this disease? We want to hear from you.

      Find a Specialist



      If you need medical advice, you can look for doctors or other healthcare professionals who have experience with this disease. You may find these specialists through advocacy organizations, clinical trials, or articles published in medical journals. You may also want to contact a university or tertiary medical center in your area, because these centers tend to see more complex cases and have the latest technology and treatments.

      If you can’t find a specialist in your local area, try contacting national or international specialists. They may be able to refer you to someone they know through conferences or research efforts. Some specialists may be willing to consult with you or your local doctors over the phone or by email if you can't travel to them for care.

      You can find more tips in our guide, How to Find a Disease Specialist. We also encourage you to explore the rest of this page to find resources that can help you find specialists.


      Healthcare Resources

        Related Diseases


        Related diseases are conditions that have similar signs and symptoms. A health care provider may consider these conditions in the table below when making a diagnosis. Please note that the table may not include all the possible conditions related to this disease.

        Conditions with similar signs and symptoms from Orphanet

        Differential diagnoses include acute intermittent porphyria and, especially, variegate porphyria (see these terms).

        Visit the Orphanet disease page for more information.



        Research helps us better understand diseases and can lead to advances in diagnosis and treatment. This section provides resources to help you learn about medical research and ways to get involved.

        Patient Registry

        • The Porphyrias Consortium is a team of doctors, nurses, research coordinators, and research labs throughout the U.S., working together to improve the lives of people with this condition through research. The Porphyrias Consortium has a registry for patients who wish to be contacted about clinical research opportunities.

          For more information on the registry see:



          Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

          Organizations Supporting this Disease


            1. Tishler, Peter. Hereditary Coproporphyria. National Organization for Rare Disorders (NORD). Updated 2014;
            2. Wang B, Bissell, DM. Hereditary Coproporphyria. GeneReviews. Updated Nov. 8, 2018;
            3. Wang B, Rudnick S, Cengia B, Bonkovsky HL. Acute hepatic porphyrias: Review and recent progress. Hepato Comm. Dec 20, 2018; 3(2):193-206.
            4. Balwani M, Wang B, Anderson KE, Bloomer JR, Bissell DM, Bonkovsky HL, Phillips JD, Desnick RJ, et al.. Acute hepatic porphyrias: recommendations for evaluation and long-term management. Hepatology. 2017; 66:1314-1322.
            5. Stein PE, Badminton MN, Rees DC.. Update review of the acute porphyrias. Br Jl Hemot. 2017; 176(4):527-538.
            6. Whatley SD, Mason NG, Woolf JR, Newcombe RG, Elder GH, Badminton MN. Diagnostic strategies for autosomal dominant acute porphyrias: retrospective analysis of 467 unrelated patients referred for mutational analysis of the HMBS, CPOX, or PPOX gene. Clin Chem. 2009; 55:1406-1414.
            7. Elder G1, Harper P, Badminton M, Sandberg S, Deybach JC. The incidence of inherited porphyrias in Europe. J Inherit Metab Dis. Sep 2013; 36(5):849-57.

            Do you have HCP and would like to share your story the APF is collecting personal journeys with HCP.  Please feel free to contact to submit your story and bring awareness to the Porphyria community.